Q. E. D., or New Light on the Doctrine of Creation
by
George McCready Price
Part 1 out of 2
Produced by Bryan Ness and PG Distributed Proofreaders
Q.E.D.
Or
New Light on the Doctrine
of Creation
By
GEORGE McCREADY PRICE
_Professor of Chemistry and Physics, Lodi Academy, California
Author of "Outlines of Modern Science and Modern
Christianity," "The Fundamentals of Geology,"
"God's Two Books," "Back to the Bible,"
"A Text-Book of General Science," etc._
"... and set you square with Genesis again."
--_Robert Browning_.
1917
_To
WILLIAM CLEAVER WILKINSON
Scholar, Critic, Poet and Christian Gentleman
This book is dedicated by one who
owes to his advice and kindly sympathy
more than can be expressed_
Preface
The great world disaster, ushered in with the dawn of that August
morning in 1914, has already brought revolutionary changes in many
departments of our thinking. But not the least of the surprises awaiting
an amazed world, whenever attention can again be directed to such
subjects, will be the realization that we have now definitely outgrown
many notions in science and philosophy which in the old order of things
were supposed to have been eternally settled.
There are but two theories regarding the origin of our world and of the
various forms of plants and animals upon it, Creation and
Evolution,--the latter assuming many modifications.
The essential idea of the Evolution theory is _uniformity_; that is, it
seeks to show that life in all its various forms and manifestations
probably originated by causes similar to or identical with forces and
processes now prevailing. It teaches the absolute supremacy and the past
continuity of natural law as now observed. It says that the changes now
going on in our modern world have always been in action and that these
present-day natural changes and processes are as much a part of the
origin of things as anything that ever took place in the past. In short,
Evolution as a philosophy of nature is an effort to smooth out all
distinction between Creation and the ordinary processes of nature that
are now under the regime of "natural law."
On the other hand, the essential idea of the doctrine of Creation is
that, back at a period called the "beginning," forces and powers were
brought into exercise and results were accomplished that have not since
been exercised or accomplished. That is, the origin of the first organic
forms, indeed of the whole world as we know it, was essentially and
radically _different_ from the ways in which these forms are perpetuated
and the world sustained to-day. _Time_ is in no way the essential idea
in the problem. The question of _how much time_ was occupied in the work
of Creation is of no importance, neither is the question of _how long
ago_ it took place. The one essential idea is that in its nature
Creation is essentially inscrutable; we can never hope to know just how
it was accomplished; we cannot expect to know the process or the
details, for we have nothing with which to measure it. The one essential
thing in the doctrine of Creation is that the origin of our world and of
the things upon it came about at some period of time in the past by a
direct and unusual manifestation of Divine power; and that since this
original Creation other and different forces and powers have prevailed
to sustain and perpetuate the forms of life and indeed the entire world
as then called into existence.
Accordingly, we might establish the Evolution doctrine by showing that
matter can be made _de novo_, that energy can be created or increased in
amount, that life can be made from the not-living, and that new and
distinct forms of life can be produced in modern times,--all by natural
law as now prevailing.
Or we can practically demonstrate the historical reality of a direct
Creation at some time in the past, if we can show that the net results
of all modern science tend to prove that the forces and processes now in
operation can never account for the origin of things; that matter, and
energy, and life, and the various forms of life must all have had an
origin essentially different from anything now going on around us.
This indicates the line of argument adopted in the following pages.
The Evolution theory has been widely discussed and accepted in modern
times. Indeed it has had a fair chance and an open field for several
decades. What is the present situation of the controversy? The friends
of the Bible and of old-fashioned Christianity need to know the real
facts of the present situation.
Every now and then the news despatches report that the great Professor
So-and-so has at last really produced life from the not-living, or has
obtained some absolutely new type of life by some wonderful feat of
breeding. Or some geologist or archaeologist has discovered in the earth
the missing link which connects the higher forms of life with the
lower, or which bridges over the gulf between man and the apes. Thus
many people who get their "science" through the daily papers really
believe that these long-looked-for proofs of Evolution have at last been
demonstrated, and hence they receive without question the confident
assertions of the camp followers of science published at space rates in
the Sunday supplements that all intelligent men of to-day have long ago
accepted the Evolution doctrine.
But in spite of the quick dissemination of news and the universal spread
of education, it seems but a slow process for the really important
discoveries of modern science to filter down through such media as the
current periodicals to the rank and file of society. The situation seems
to illustrate the old adage that a lie will travel round the world while
truth is getting on her shoes. _Thus it happens that the common people
are still being taught in this second decade of the twentieth century
many things that real scientists outgrew nearly a generation ago, and
assertions are still being bandied around in the individual sciences
which are wholly unwarranted by a general survey of the whole field of
modern natural science_. Indeed, in almost every one of the separate
sciences the arguments upon which the theory of Evolution gained its
popularity a generation or so ago are now known by the various
specialists to have been blunders, or mistakes, or hasty conclusions of
one kind or another. Thus the market value of all the various subsidiary
stocks of the Evolution group has been steadily declining in their
respective home markets, and now stands away below par; while strange to
say the stock of the central holding company itself is still quoted at
fictitiously high figures.
This curious--not to say deplorable--situation has developed largely
because of the modern system of strict specialization in the various
departments of science. Each scientist feels compelled by an unwritten
but rigid code of professional ethics to confine himself strictly to the
cultivation of the little plot of ground on which he happens to be
working, and is forbidden to express an opinion about what he may know
has been discovered on another plot of ground on which his neighbor is
working, except by express permission. In other words, science teaching
has now become strictly a matter of authority, this authority being
vested in the various specialists; and nobody is permitted to look at it
in a broad way, or to frame a general induction from the sum of all the
facts of nature now discovered, under penalty of scientific
excommunication. The scientific code of ethics forbids any general view
of the woods: each man must confine himself to the observation of the
particular tree in front of his own nose.
But these pages have been prepared under the idea that it is high time
to take a more general survey of the geography, time to take our eyes
off the various individual trees, and to look at the woods. Perhaps in
some respects they may be regarded as too technical for ordinary
readers. But if this is the case, it is because the writer had to choose
between this somewhat technical treatment of the subject and the
alternative danger of making loose and inaccurate statements or dealing
in glittering generalities too vague to carry conviction. As it is, the
writer is here trying to give directly to the general public the results
of years of special research in correlating the data from many scattered
departments of science,--results that most scientists would feel obliged
to reserve for the select few of some learned society, to be published
subsequently in the Reports of its "Transactions," and to find their way
after years of delay into the main currents of human thought. But these
dilatory methods of professional pedantry, miscalled "ethics," shall not
longer be allowed to delay the publication of highly important
principles which the public are entitled to know at once, and to know at
first hand. Then, too, it is more than doubtful if any purely academic
body could be found willing to become responsible for giving to the
world conclusions so contrary to the vogue of the present day.
That these brief chapters may clear up the doubts of some, and encourage
the faith of many, is the object of their publication in this
non-professional form.
G. McC. P.
Contents
I. MATTER AND ITS ORIGIN 15
II. THE ORIGIN OF ENERGY 31
III. LIFE ONLY FROM LIFE 43
IV. THE CELL AND THE LESSONS IT TEACHES 57
V. WHAT IS A "SPECIES"? 68
VI. MENDELISM AND THE ORIGIN OF SPECIES 78
VII. GEOLOGY AND ITS LESSONS 99
VIII. CREATION AND THE CREATOR 125
I
MATTER AND ITS ORIGIN
I
When we were told by a prominent scientist just the other day that
"electricity is now known to be molecular in structure," it almost took
our breath away. And when we were informed that certain well-known
chemical elements had been detected in the very act of being changed
over into other well-known elements, with the prospect of such a
transformation of the elements being quite the normal thing throughout
nature, the very earth seemed to be slipping away from under our feet.
Some of the closely related discoveries, such as the fact that the
X-rays show a spectrum susceptible of examination, were not so
disconcerting in themselves; but the marvellous pictures of the
structure of the atom elicited by these discoveries made many good
people almost question whether our venerable experimenters had not been
indulging in pipe dreams amid their laboratory work.
Do we, then, begin to understand the real composition of matter? Does it
have component parts, in the materialistic sense; or is what we call
_matter_ only a mysterious manifestation of energy? And if the latter
be our answer, can we hope to settle the problem objectively and so
conclusively that it will stay settled? In short, do we, regarding these
border-line subjects between metaphysics and natural science, know
anything more than our fathers and our grandfathers?
It will be convenient to consider these problems under two heads: the
composition of matter, and the origin of matter.
II
1. It was long ago recognized that matter must be composed of particles
which are driven farther apart by heat and are brought closer together
by cold, thus laying the foundation for the theory of the molecular
composition of matter. But not until the time of Dalton, about a hundred
years ago, was it proved that the molecule itself, the unit of physical
change, is capable of definite division into atoms, the units of
chemical change. This conception of the molecules and atoms as the
ultimate units of which matter is composed maintained its place until
the discovery of radioactivity and its associated phenomena, about
1896; since which time we have definitely ascertained that even the
atoms are separable into still smaller units, and that possibly these
units are _all alike_. On this last possibility, it would surely be a
most amazing fact if such multitudinous "properties" of bodies could be
produced merely by variations in the arrangements of these ultimate
units into atoms, or in some other way which produces vast differences
in properties by combinations of units that are nevertheless mere
duplicates of one another.
As hydrogen is the lightest of the elements, it has been a favorite
theory with scientists that the various elements are all composed of
combinations of hydrogen atoms. But since many of the elements have
atomic weights which cannot be made exact multiples of that of hydrogen,
it has been felt that there must be some other smaller unit than the
hydrogen atom; or else that these hydrogen atoms themselves change in
weight when they combine to form other atoms. But mass seems to be the
one unchangeable characteristic of matter; hence it was felt that any
change of weight is almost unthinkable, and so a solution was sought in
the direction of still further dividing the hydrogen atom, the smallest
unit concerned in chemical change, as then understood. But now the facts
and principles brought to light in connection with the studies of
radioactivity have settled it that we actually do have a much smaller
unit than the hydrogen atom, one of only about 1/1760 its mass, in fact;
and that this smallest of the small things of nature is none other than
a particle of negative electricity, now called an _electron_.
That the atoms of all the elements must have a common unit of
composition, that they behave as if composed of ultimate particles that
may be regarded as duplicates of one another, has long been regarded as
an inevitable conclusion from the Periodic Law of Mendeleef. This law
says that the physical as well as the chemical properties of the various
elements depend upon their atomic weights, or as it is stated in the
language of mathematics, the properties of an element are functions of
its atomic weight. This fact of the variation in the properties of
elements in accord with their atomic weights has been even more
strikingly illustrated by the behavior of discharges of electricity
through rarified gases, as well as by the facts of radioactivity. To
quote the words of Sir J.J. Thompson, "The transparency of bodies to
Roentgen rays, to cathode rays, to the rays emitted by radioactive
substances, the quality of the secondary radiation emitted by the
different elements, are all determined by the atomic weight of the
element."[1]
[Footnote 1: Encyclopaedia Britannica, Vol. XVII, 891. Cambridge
Edition.]
Just recently we have had opened up before us a still more intimate
inner-circle view of the composition of matter. H.G.J. Moseley, a young
man only twenty-six years of age, at an English university, devised a
method of examining the spectra of the various elements by means of the
X-rays. He found in this way that the principal lines of these various
spectra are connected by a remarkably simple arithmetical relationship;
for when the elements are arranged in the order of their atomic weights,
they show a graded advance from one to another equal to successive
additions of the same electrical unit charge, thus indicating a real
gamut of the elements that we can run up by adding or run down by
subtracting the same unit of electrical charge. It is pitiable to have
to record that next year this scientific genius was killed in the
ill-fated Gallipoli expedition against Turkey.
Thus in many fairly independent ways we are brought around to this same
idea of a common structure underlying all the many seeming diversities
manifested by what we call matter.
The phenomena of radioactivity were discovered accidentally in 1896 by
the French chemist Becquerel. Many investigators immediately began
working along this promising line, and two years later Madam Curie, in
association with others, discovered the new element radium. Soon it was
discovered that radium and several other substances are continually
giving off radiations at an enormous rate, that no change of chemical
combination, no physical change of condition appears to have the
slightest effect in slowing or increasing this discharge of emanations,
while no scientific apparatus yet devised can detect any change in the
substances left behind either in respect to weight or any other
properties as the result of these enormous losses of energy. Accordingly
some people not unnaturally were ready to draw the conclusion that those
most firmly established laws of physics and chemistry, the laws of the
conservation of energy and of matter, were overthrown by this
astonishing behavior of these newly discovered substances. However, only
a few more years of study and investigation were necessary to prove
that this last conclusion was wholly unwarranted; and to-day these laws
of the conservation of energy and of matter are more firmly established
than ever.
The thing that has gone by the board is the old idea of the atoms as the
indivisible and irreducible minima of the material universe. For not
only do all the radioactive substances give off particles of helium gas
positively electrified, but _all bodies, no matter what their
composition_, can by suitable treatment, such as exposing them to
ultra-violet light, or raising them to incandescence, be made to _give
off electrons_ or negatively charged particles, and _these electrons are
always the same no matter from what kind of substance they come_. In a
somewhat similar way, we always get positively electrified particles of
the mass of the hydrogen atom, or about 1,760 times the mass of the
electron, whenever we send an electric charge through a gas at very low
pressure, _no matter what the kind of gas_. Whether or not these
positive units will yet prove susceptible of being split up into smaller
particles comparable to the electrons, is merely a subject for
conjecture. We have no proof that they will. At the present time what we
call matter seems to be composed of these positive units and of the
electrons which are about 1/1760 as great; and in the present state of
our knowledge these facts suffice to explain all the properties of
matter. Thus we can either say that electricity is composed of matter,
or say that matter is composed of electricity; and human language at
best is such a clumsy vehicle of thought that scientifically and
philosophically the one statement is as correct and as reasonable as the
other.
And probably we shall never be able to learn any more than this. We have
arrived at a sort of box-within-a-box theory of the make-up of matter.
By a very elaborate system of unpacking, or by some violent external
force that makes the inside burst open, as it were, we seem to be able
to make pieces fly off from the atoms, these pieces being then projected
into space with enormous force and velocity. There are theories galore
of the structure of the atom; but as Prof. E.P. Lewis has said, most of
these theories are so impossible as to be absurd, or so speculative that
"they suggest no experimental tests for their validity."[2] Just at
present Rutherford's theory of the structure of the atom is quite
popular. This postulates a nucleus composed of a group of positive units
and electrons, with an excess of the positive charges equal to half the
atomic weight, with an equal number of electrons circulating about this
nucleus in rings. Bohr's theory, which is not very different from this,
has perhaps even more friends, and it is supported by the remarkable
discoveries of the lamented Moseley. But we must not take such theories
too seriously. As Kayser has said, any true theory of the make-up of the
atoms must assume an absolutely full and perfect knowledge of all
electrical and optical processes, and is therefore beyond our dreams. Or
as Professor Planck said in his Columbia lectures, we are not entitled
to hope that we shall ever be able to represent truly through any
physical formulae the internal structure of the atom.
[Footnote 2: _Nature_, April 5, 1917.]
III
2. We must now take up the second phase of our subject, the problem of
the origin of matter.
Before we knew anything of radioactivity we could have dismissed such a
subject briefly by quoting the law of the conservation of matter, which
says that matter can neither be created nor destroyed by any means known
to science. By our knowledge of radioactivity we can make our answer a
little more learned, a little less abrupt, but none the less
discouraging to the advocate of the development hypothesis. We can tell
how the elements of high atomic weight, such as uranium and thorium, are
constantly giving off particles and are thus by loss or decomposition
being changed over into other elements, such as radium, niton, polonium
and lead. But our new knowledge compels us ultimately to give the same
answer as before, namely, that _we still do not know how matter ever
could have originated_, except that "in the beginning" it was called
into existence by the fiat of Him whom we Christians worship as our God,
the Creator. Thus we reach the conception of the universe as that of a
great clock gradually running down, which is certainly the antithesis of
that picture so long held before us by the advocates of the development
theory.
Uranium is a rather rare element, though known for over a hundred years,
and has an atomic weight of 238.5. In decomposing it gives off first a
helium atom, weight 4; and after this action has been repeated three
times the substance left is radium, atomic weight about 226.4. Thus
radium is simply uranium after it has lost three helium atoms. Radium in
its disintegration gives off three kinds of particles, namely, helium
atoms (positively electrified), [Greek: b]-rays or electrons, and
[Greek: g]-rays, the latter being identical with the X-rays, and having
penetrating power sufficient to carry them through six inches of lead or
a foot of solid iron. The final stage in this process of disintegration
is the ordinary element lead, in which condition the atoms seem to have
reached relative stability. Whether or not our stock of lead, with our
other common elements that are not radioactive, was originally produced
by the disintegration of these other elements, is merely a matter of
conjecture. We know nothing at all about it.
The length of time it takes for half the atoms of an element to change
is called its "life" or period. The periods of most of the radioactive
substances have been calculated, that of uranium being very long. The
calculated period of radium is 2,500 years, while that of polonium is
only 202 days, and that of niton 5.6 days. These unquestioned facts,
together with the enormous amount of heat evolved by the disintegration
of these substances (that from radium being about 250,000 times the heat
evolved by the combustion of carbon), have thrown a great deal of doubt
upon the older estimates of the age of the earth.
The discussion of the details of these theories would be unprofitable.
But through the mists of all these conflicting theories and
probabilities two facts of tremendous importance for our modern world
emerge in clear relief, namely, that the grand law of the conservation
of matter still holds true, and hence that _the matter of our world must
have had an origin at some time in the past wholly different in degree
and different in kind from any process going on around us that we call a
natural process_. These elements of high atomic weight that break down
into others of lower atomic weight may be so rare because they have been
about all used up in this process. At any rate, so far from revealing
the origin of matter as a process now going on, these phenomena are an
objective demonstration that all matter is more or less unstable and
liable under some unknown but ever-acting force to lose some portion of
that fund of energy with which it seems to have been primarily endowed.
_Not the evolution of matter but the degeneration of matter_ is the
plain and unescapable lesson to be drawn from these facts. The varieties
of matter may change greatly, and one variety or one chemical element
may be transformed into another. But this transformation _is by loss and
not by gain_. It is degeneration and not upward evolution that is now
opened up before our astonished eyes by this peep into the ultimate
laboratories of nature; and he is surely a blind observer who cannot
read in these facts the grand truth that all this substance called
matter with which science deals in her manifold studies must at some
time in the past, I care not when, have been _called into existence in
some manner no longer operative_. The past eternity of matter, as well
as its progressive development from the simple to the complex, seems
manifestly out of consideration in view of the facts as we now know
them. There is no ambiguity in the evidence. So far as modern science
can throw light on the question, there must have been a real Creation of
the materials of which our world is composed, a Creation wholly
different both in kind and in degree from any process now going on.
IV
A supposed objection has been raised to this view, based on the vastness
of the universe as we now know it. Whether or not the universe is really
infinite in extent, it is certainly of an extent that is practically
infinite, so far as our powers of observation or of reasoning are
concerned. But this practically infinite universe is not a bit harder to
account for than would be a definitely limited universe, say of the size
of our solar system. If the spectroscope shows that the far distant
parts of the universe contain many of the same elements as are found in
our solar system, we need not be surprised, since all are alike the
work of the same Creator. Nor would this fact that the universe seems to
be composed of similar materials throughout tend in any way to prove
that all these parts of the universe were brought into existence at the
same time, nor yet that our solar system was refashioned out of some of
the common stock of the universe already on hand, as the nebular
hypothesis supposes. For all that we can tell to the contrary, it would
seem probable that the materials of our solar system were called into
existence expressly for the position they are now occupying; and this
seems to be the plain import of the record in Genesis. Of one thing,
however, we can be certain,--these materials must at some time have been
called into existence by methods or ways that are no longer in operation
around us. "In the beginning God created the heaven and the earth."
V
Some remarks are necessary here regarding the homogeneousness of matter,
or the idea that the various elements are composed of primordial units
which are themselves alike, mere duplicates of each other. If this
should prove to be really the case, as seems to be quite likely in the
light of the facts given above, would it not be a veritable triumph for
materialism? By no means. On the contrary, I think I can show in a very
few words not only that this homogeneousness of matter is the only
rational view of the composition of the material universe, but also
that it is the only view consistent with Christian Theism and with the
doctrine of Creation.
The theory of the atoms with their inherent and unchangeable properties,
which prevailed during the greater part of the nineteenth century,
naturally led us to look upon these properties as inherent in the things
themselves. This was indeed materialism. This view, however, constantly
impelled us to find out the essential differences between the various
kinds of atoms, so as to "account for" their varying behaviors. And no
matter how far we push such inquiries, this materialistic attitude of
mind will control us so long as we think we are dealing with substances
which are intrinsically different. If the differences are innate or
inherent in the things themselves, we must naturally endeavor to find
out why and how they are different; and no matter how far we go along
this road we are always headed in the direction of stark materialism. On
the other hand, to say that the "properties" of the atoms are not
inherent in themselves, but are imposed on them by an external
ceaselessly acting power, the will of the Creator, would be in full
accord with Biblical theism; and then we might naturally say that the
ultimate particles of which matter is composed may well be regarded as
alike and mere duplicates of one another. And this, as we have seen, is
just what modern discoveries in radioactivity are teaching us regarding
the make-up of the substances that we call matter.
But an objection at once arises. How can these primordial units of which
matter is composed behave so differently, if they are really alike, mere
duplicates of one another?
We may not as yet be able to tell just why and how; but we have in the
cells of which all plants and animals are composed an analogy which is
almost perfect, if not quite.
These component units of organic matter, the individual cells, as will
be explained later, seem physically and even chemically mere duplicates
of one another. They may not all be of the same size; but they are all
composed of protoplasm, and the protoplasm of plants cannot be
distinguished from that of animals by any physical or chemical tests
known to modern science. The protoplasm in the brain of a bird is the
same as that in its toes; and no metaphysical subtilties about heredity
have ever explained why the one does a different work from the other.
The plain fact is that different cells, composed of identical protoplasm
and structurally alike, _act very differently_; and there is no
scientific reason based on innate properties that gives us even a
glimmer of a reason why. We have searched a long time along this road;
but there is no prospect of finding an explanation; we are merely
running up a _cul-de-sac_ with no view beyond. From the materialistic
point of view, nobody knows why protoplasm acts as it does, _least_ _of
all, why some masses of protoplasm act one way, and exact duplicates act
differently_. But if, on the other hand, we look beyond the facts and
methods of physics and chemistry, and even beyond the most plausible
theories of genetics, we can readily explain this remarkable action of
the cells as the result of the will of an ever acting, omniscient,
almighty God. Certainly nothing else is adequate to explain the behavior
of living cells.
In a very similar way we must reason regarding the ultimate units of
matter, call them what we will, electrons, corpuscles, or units of
electricity. If these are mere duplicates of each other, as science now
teaches, they not only indicate by this identity that they are
"manufactured articles," as was long ago pointed out of the atoms and
molecules, but they also indicate with all the force of a demonstration
that nothing but an ever present omniscient Intelligence _could keep
these duplicates from always acting the same_ under similar external
forces. If gold and carbon, iron and oxygen are at bottom composed of
particles that are mere duplicates of each other, as seems to be the
case, how can these elements and the six dozen or more others maintain
their individuality throughout nature as we know they do, even in the
far distant stars, except by the sleepless care of an Intelligence whose
Word is as effective in one part of the universe as in another, and to
whose Word these particles of matter can show no inertia and no
disobedience, because they have no powers or properties except what He
has imparted? This doctrine of the homogeneousness of matter is the
antithesis of materialism. It is consistent only with the doctrine of an
almighty and ever present God, and like many other facts which have been
developed by modern scientific discoveries, it confirms the other primal
doctrine of a literal Creation "_in the beginning_."
VI
The conclusion which our minds are forced to draw from the facts
presented in this chapter is not doubtful, nor is it difficult to state.
Matter is not now being brought into existence by any means that we call
"natural." _And yet the facts of radioactivity very positively forbid
the past eternity of matter_. Hence, the conclusion is syllogistic:
matter must have originated at some time in the past by methods or means
which are equivalent to a real Creation.
Thus far, at least, the record of Genesis is confirmed: "In the
beginning God created."
II
THE ORIGIN OF ENERGY
I
What has been regarded by many as the greatest scientific triumph of
modern times was worked out about the middle of the last century by
James Prescott Joule and others, in determining that a certain amount of
mechanical energy is exactly equivalent to a definite amount of heat.
With this mechanical equivalent of heat all the various other forms of
energy have also been correlated; until now we have the general law of
the Conservation of Energy, which says that energy can be neither
manufactured nor destroyed, but merely transformed and directed. And
this magnificent law, like that of the conservation of matter, is strong
evidence that there must have been a real Creation at some time in the
long ago, different not merely in degree but in kind from anything known
to modern science.
Joule worked out the mechanical equivalent of heat by means of his now
famous experiment of churning water. He reasoned that if the heat
produced by friction, etc., is really energy in another form, then the
same amount of heat must always be generated by the expenditure of a
given amount of motion or mechanical work. And this must be true, no
matter whether this work is expended in overcoming the friction between
wood on wood, iron on iron, or in any other conceivable way.
Accordingly, he devised an experiment in which paddle wheels were made
to rotate in a vessel of water by means of falling weights somewhat like
the weights of a clock. The amount of work represented by the falling of
the weights was easily calculated, and so was the amount of rise in
temperature of the water caused by the friction of the water with the
rotating paddle wheels. In various other ways he measured the amount of
heat generated by a measured amount of work; and as the result of all
his experiments (with very slight corrections made since by means of
more exact apparatus), we now know that 778 foot pounds of work produce
heat enough to raise one pound of water one degree Fahrenheit; or stated
in the metric system, 427 kilogram meters of work will produce a calorie
of heat.
Since these record-making experiments by Joule, the matter has been
verified over and over again in all sorts of ways; and almost every kind
of display of energy has been measured with more or less exactness. Even
the amount of food oxidized in the human body is now known to be capable
of correlation with the other forms of energy, though necessarily very
minute exactness of measurement is scarcely attainable in this case. But
no scientist of to-day doubts that all the physiological processes of
animals or of plants conform exactly to the law of the conservation of
energy that energy is neither created nor destroyed by any means known
to science. In other words, the amount of energy in our world, if
science can at all determine such a matter, seems to be _a fixed
quantity_, gradually being dissipated into space, it is true, but
momently replenished from the sun at exactly the same rate now as
hundreds or thousands of years ago. And while this energy is in our
world it is always capable of exact correlation in all of its
multitudinous forms, and is transformable back and forth without
increase and without loss.
On the discovery of the radioactive substances in 1896, some persons
hastily concluded that the law of the conservation of energy was
contradicted by the astonishing way in which these substances acted. But
further and more accurate experiments have set this matter at rest, as
indeed might have been expected; for the law of gravitation itself is
not more immovably established in the make-up of the universe than this
magnificent law that energy cannot be created by any means which we call
natural.
In all ages there have been men who have spent their lives in the vain
effort to invent a machine out of which work could constantly be
obtained without the expenditure upon it of an equal amount of work. But
the United States patent office has got so tired of receiving
applications for patents based on this idea of perpetual motion that
they have long since refused to issue any such patent where this
principle is the manifest object; and I suppose the governments of other
countries have taken a similar stand. And why? Because they know that
energy cannot now be created by any device, no matter how ingenious; and
they refuse to become a party to any scheme that seems to imply that
this modern creation of energy is within the bounds of possibility.
Yet what is all this but a confirmation of the declaration long ago made
that "the works were finished from the foundation of the world" (Heb.
4:3)? True, the energy we are constantly employing seems to come to us
from the sun; but we must remember that the sun and its family of the
solar system, including the earth, were all made at the same time, that
they are bound together as parts of an indissoluble whole. Accordingly,
no one can say that the total amount of energy called into existence at
the creation of our solar system is being added to at the present time.
At any rate, so far as modern science can judge of the matter, the total
amount of energy available for our world _is a fixed quantity_; and its
amount and the terms on which it was to be available for our use were
fixed or finished "from the foundation of the world." While it is a very
significant fact in this connection that with all the multiform
speculations which have been made as to the physical source of the sun's
heat, no explanation wholly satisfactory has yet been made as to how
this energy coming to us from the sun is constantly replenished or
maintained.
II
The desire to find a material cause for all phenomena is instinctive in
the human mind, and has proved the chief impetus in a thousand
discoveries. And yet, unless we are on our guard, it is liable to be a
source of real error whenever we are dealing with the deeper problems of
thought. For when we have pushed our way into the inner sanctuary of any
department of nature, we almost invariably come upon a deep chasm that
we can pass over only by building a bridge of words. Some of these
verbal bridges have been decorated with very dignified names, such as
"the luminiferous ether," "gravity," "chemical affinity"; and when we
have shifted from the one side of the chasm to the other we impose upon
the credulity of the public (and even ourselves) by giving out the
impression that these words represent the real objective bridge on which
we crossed.
In how many ways do we by our theories dodge the crucial problem of how
energy is really transmitted, that is, how matter can act on distant
matter across seemingly vacant space. Gravity, and indeed all the forms
of the attractive forces, come under this head. True, we observe certain
regularities in the way in which these phenomena occur, and the
phenomenon at one place seems to be somehow dependent on some exercise
of force at another place. And so we invent an ingenious theory, and
fortify it all around with ponderous algebraic artillery for defense
against all attack. And by persistent use of such theories we hypnotize
ourselves into the belief that we are truly scientific in method, and
are dealing with objective realities, and that these learned theories
are something more than pretentious masks to hide our ignorance of real
nature; when in reality these theories seem to be only a material screen
to shield us from an embarrassing near view of the immediate action of
God in all the various phenomena of the world; for not many find it a
comfortable thought thus to live continuously beneath the great
Taskmaster's eye.
The theory of the luminiferous ether as the medium of the transmission
of light is one of these pretentious bridges of words. Our advancing
knowledge of electro-magnetic phenomena may some day drive us back to a
modified form of the corpuscular theory of light, and then we can throw
this of the ether to the winds. In that case we would at least have a
real material cause for the phenomena with which we deal. While the
current theory of the ether has so many inconsistencies, and attempts to
bridge over so many real chasms in our thinking that it seems truly
astonishing to see it taught so long. By the theory of the ether the
problems are not solved, they are merely postponed or evaded; for while
solving one difficulty it creates a multitude of its own. How then are
we better off than before without any such theory?
Being at liberty to invent any sort of qualities for their ether,
scientists have tried to imagine such a substance as they think they
need. The ether must be a kind of matter; but unlike any matter that we
know of it cannot have weight, or else it would gravitate together here
and there, thus becoming more abundant in some places than in others;
whereas the _need_ is for a material absolutely uniform throughout
space, even throughout the interiors of solid bodies, such as the earth
and the bodies upon the earth.
Another reason for supposing the ether to be a _plenum_, filling
absolutely all space, is that it must be perfectly frictionless; and for
this reason it cannot be composed of particles with spaces between them.
It must be frictionless, for otherwise the planets would be retarded in
their motions through space. The earth, for instance, is moving along
its orbit at the rate of eighteen miles a second; and yet the ether does
not pile up in front of it, nor is it made rarer in the wake of the
earth. Moreover, during the thousands of years during which astronomers
have been making observations absolutely no retardation has been
detected in the motions of the earth or of any of the heavenly bodies,
even to the smallest fraction of a second.
It is necessary to make the ether absolutely elastic and absolutely
rigid. We are acquainted with many materials that are elastic, and with
some that are comparatively rigid. But the elastic substances that we
are acquainted with are not rigid, and the rigid substances are not
elastic; and to assume such contradictory qualities in the ether
transports us far beyond the bounds of experimental science.
These are but a few of the difficulties raised by the assumption of the
ether as a real entity; but as there is no means of demonstrating its
existence, except by arguing the _necessity_ of having such a medium to
transmit radiant energy, it follows that no multiplication of objections
to the theory is likely to refute it in the minds of those who feel this
necessity. Those who refuse to admit the possibility of "action at a
distance," who insist on inventing a connecting material medium between
every observed effect and some material object with which it seems to be
in causal connection, will, I suppose, have to be allowed to exercise
their ingenuity in any way to satisfy their minds, even though they may
have to revise their theory with every fresh discovery in optics or
radioactivity.
There are many other ingenious mental devices, like this of the ether,
which seem to me only materialistic efforts to postpone or to dodge the
real vital lessons to be read from natural phenomena,--efforts to push
the real Cause back one step farther into the shadow,--a last desperate
effort, in the face of the constantly accumulating evidence of modern
knowledge that the great First Cause is far more intimately connected
with life and motion than many are willing to believe. We have already
mentioned gravity and the other attractive forces, such as cohesion and
adhesion; but seemingly very few people have ever paused to consider how
utterly inexplicable they still remain in any physical or materialistic
sense.
It is easy to explain any form of a _push_ in a physical way; but
gravity is _not a push but a pull_. And how are we to explain the method
by which a body can act where it is not, how explain in detail the way
by which it can reach out and pull in toward itself another separated
body, and exert this pull across the immeasurably wide fields of space?
The law of inverse squares may tell us very accurately the manner in
which the results are accomplished, for our Creator is a God of order.
But there is no materialistic theory of the _why_ of gravitation that is
worth employing the time of sensible, truth-loving people. And we can
rest assured that there never will be any such real "explanation," save
that this is the way which the great Jehovah has ordained. Since such
theories only explain the known in terms of the unknown, they can serve
only as a sort of mental buffer or shield between us and the conception
of the direct working of a personal God, whose word must always be as
effective throughout the remotest corners of His universe as near at
hand, for the very simple reason that matter has no "properties" which
He has not imparted to it, and accordingly it can have no innate inertia
or reluctance to act which God's word would need to overcome in order to
induce it to act, even when this word operates across the wide fields
of space. On this explanation these phenomena of "action at a distance"
are at least intelligible; while to me, and I speak now as a scientist,
they are intelligible in no other way.
III
There is another line of thought which has to do with living organisms,
but which I shall beg leave to anticipate and bring in here at the close
of this chapter, since it follows as a direct corollary from the law of
the Conservation of Energy. Indeed, we might even term it the biological
aspect of that law.
As we have seen, we can neither create energy nor destroy it; though we
can _lose it_,--so far as this earth is concerned. The vast fund of
energy that daily comes streaming to us from the sun is transmuted back
and forth in a thousand ways, though little by little it is dissipated
off into space, and we are dependent upon a fresh supply from the ever
replenished fountain.
Just so, though in a somewhat idealistic sense, is it with what we may
term vital energy. Cells, organisms, even whole races, are subject to
degeneration and decay. They cannot acquire higher powers, though they
may gradually lose what they already have; as Bateson has recently told
us that whatever evolution there is must be by loss and not by gain.
Water very easily runs down hill; but cannot go up hill in and of
itself. Just so with the types of organic life. It was not merely an
idle sneer of the witty Frenchman, that science has not yet explained
how an ancestor can transmit what he has not got himself. He cannot
always transmit all that he himself actually possesses of nature's
gifts. Vitality becomes lowered, and the type degenerates. Weismann has
emphasized this idea in his doctrine of "panmixia," or the withdrawal of
selection, which always results in degeneration. Selection, artificial
or natural, may serve to counteract this universal tendency of organic
life, but only approximately. As Sir William Dawson says, "All things
left to themselves tend to degenerate." Little by little the endowment
of vitality bestowed upon our world at the beginning has, like radiant
energy, been returned to God who gave it; but, unlike the case of
radiant energy, the Creator has not established any regular source of
vital supply from without, no elixir of life for organic nature in
general. There is no longer within easy reach a tree of life from which
we may pluck and eat and live forever. And as the individual grows old
and dies, so do species and even whole tribes degenerate and become
extinct.
"From scarped cliff and quarried stone
She cries, 'A thousand types are gone.'"
The glorious flood of vitality, so prodigally lavished upon our world in
the beginning, has been ebbing lower and lower; and the theory of
organic nature steadily advancing from the lower to the higher is
manifestly just as puerile as the old hope of creating energy by a
perpetual-motion machine,--and a mistake of precisely the same nature.
Both are contradicted by the magnificent law of the Conservation of
Energy, which, as we have said, is only the scientific expression of the
Scriptural statement that Creation is completed, so far as our world is
concerned; though, as the "wages of sin," death has been decreed upon
the individual, and degeneration more or less marked upon every organic
type. The fossils of the past, as well as our own experience within the
historic period, confirm the view already arrived at on other grounds
that _Creation is a completed work and is not now going on_; and the
universal testimony from organic nature is that degeneration and decay
have marked the history of every living form. Just as the individual
grows old and dies, so do species degenerate and become extinct.
III
LIFE ONLY FROM LIFE
"No biological generalization rests on a wider series of observations,
or has been subjected to a more critical scrutiny, than that every
living organism has come into existence from a living portion or
portions of a pre-existing organism."[3]
"Was there anything so absurd as to believe that a number of atoms, by
falling together of their own accord, could make a sprig of moss, a
microbe, a living animal? ... It is utterly absurd.... Here scientific
thought is compelled to accept the idea of creative power. Forty years
ago I asked Liebig ... if he believed that the grass and flowers, which
we saw around us, grew by mere mechanical force. He answered, 'No more
than I could believe that a book of botany describing them could grow by
mere chemical force.'"[4]
"Let them not imagine that any hocus-pocus of electricity or viscous
fluids would make a living cell.... Nothing approaching to a cell of
living creature has ever yet been made.... No artificial process
whatever could make living matter out of dead."[5]
[Footnote 3: P.C. Mitchell, in Encyclopaedia Britannica, Vol. III, p.
952.]
[Footnote 4: Lord Kelvin in the London _Times_, May 4, 1903.]
[Footnote 5: Lord Kelvin, to a class of Medical Students, October 28,
1904.]
I
Ever since Rene Descartes, in his Holland laboratory, dissected the
heads of great numbers of animals in order to discover the processes of
imagination and memory, men have been seeking a physical or
materialistic answer to such questions as, What is life? What is it to
be alive? How shall we distinguish the living from the not-living?
No one of to-day, in the light of the correlation of vital processes
with the general law of the conservation of energy, believes that life
in plants and animals is a separate entity which may exist outside of
and apart from matter. In a scientific sense, we only know life by its
association with living matter, which in its simplest form is known as
_protoplasm_. The latter has been termed the physical basis of life, and
so far as we know every material living thing is composed wholly of
protoplasm and of the structures which it has built up.
This grayish, viscid, slimy, semi-transparent, semi-fluid substance,
similar to the white of an egg, is the most puzzling, the most wonderful
material with which science has to deal. Chemically it is composed of
various proteids, fats, carbohydrates, etc., and these in turn of but
very few elements, all of which are common, and none of which are
peculiar to protoplasm itself. And yet its essential properties, its
mechanical as well as its chemical make-up, have baffled the resources
of our wisest men with all their retorts and microscopes and other
instruments of precision.
Protoplasm is essentially uniform and similar in appearance and
properties wherever found, whether in the tissues of the human body, in
a blade of grass, or in the green slime of a stagnant pool. And yet
probably no two samples of protoplasm are ever exactly similar in all
respects, though we may never be able to detect their precise
differences. These differences are due to the fact that the stuff is
_alive_, and within it are constantly going on those changes
accompanying metabolism, or the building up and tearing down processes
that always accompany life. All separate masses of protoplasm, such as
the one-celled amoeba or the individual cells of our own bodies, are
constantly taking in food and as constantly throwing off wastes. Hence,
in the very nature of things, it is impossible to find any mass of
protoplasm absolutely pure. And a further and impassable barrier to
chemical analysis, or indeed to any adequate scientific examination,
lies in the fact that we can never deal with protoplasm exactly as it
is, since no analysis can be performed upon it without destroying its
life. And yet even dead protoplasm, and especially its most
characteristic constituent, _proteid_, has been found the most difficult
material in the world to analyze, and nobody as yet pretends to know its
exact chemical make-up.
The constant effort of natural science to press back the boundaries of
the unknown is very liable to obscure some of the things most essential
to any system of clear thinking regarding these matters. We are so prone
to think that if only our microscopes were a little stronger, if only we
could devise more effective methods of staining or of chemical analysis
or chemical synthesis, we might really find out what life is, or what
matter itself is; in short, that we might be able to solve in a
scientific way the old, old riddle of existence. But already we have
about reached the limits of the powers of the microscope; and even if we
could devise a way of seeing the ultimate structures of which protoplasm
is composed, how would we be any better off? Would we not have to
attribute to each constituent of this living substance the properties
which we now attribute to the whole?--that is, the properties which we
attribute to masses of protoplasmic units, such as plants, or birds, or
human beings?
We look at ourselves and we feel sure that we have a separate and real
existence, that we are rationally conscious and are endowed with choice
and free will. We can say almost as much for an intelligent bird or dog.
But we hesitate to say how many of these powers or characteristics of
free and independent personality can be assigned to the unicellular
organisms, such as the amoeba or the corpuscles of our blood. These
one-celled creatures are also alive, are just as truly alive as are
those composed of many cells. Even the corpuscles of which our bodies
are composed move, and eat, and grow, and seem really endowed with
intelligence like the higher forms of life. Suppose we could go further
than is now possible and could lay bare the ultimate make-up of the
_chromatin_ of these one-celled creatures, would we even then be able to
prove that life with all its properties is inherent in these material
components of the cells? In other words, would we really solve anything
after all? Or would we not rather be compelled to acknowledge that the
simplest, the most truly rational view of the question is that in living
matter we have merely a special manifestation of the presence and the
direct action of the God of nature which we cannot so readily recognize
in not-living matter? This, it seems to me, is all that we really know,
and all that we are likely ever to know.
When we examine carefully the differences between the living and the
not-living, we see that the chief difference between them is in _their
origin_. The matter of growth is not a real distinction; for crystals
grow on the outside, while inorganic liquids grow by intussusception, as
when a soluble substance is added to them, in very much the same way as
an animal grows by the ingestion of food. Even movement is hardly an
absolute distinction between the living and the not-living; for no
movement can be detected in quiescent seeds, which may lie dormant for
thousands of years; and on the other hand inorganic foams when brought
into contact with liquids of different composition display movements
that very closely simulate those of the living matter. Lastly,
irritability, though so notably characteristic of living matter, is
scarcely peculiar to it, for many inorganic substances seem almost as
definitely responsive to external stimulation. But in the matter of
_their origin_ there is a real and a most fundamental difference. All
living substance arises only from other substance already living. It
cannot arise from the not-living; or at least it never has done so since
the beginning of scientific observation, though on this point have been
concentrated the learning and the laboratory technique of thousands of
chemists and microscopists.
It may not be out of place to quote here from one of the classics
dealing with this subject,--words that are just as true to-day as when
first written nearly half a century ago:
"Let us place vividly in our imagination the picture of the two great
kingdoms of nature,--the inorganic and the organic,--as these now stand
in the light of the Law of Biogenesis. What essentially is involved in
saying that there is no spontaneous generation of life? It is meant that
the passage from the mineral world to the plant or animal world is
hermetically sealed on the mineral side. This inorganic world is staked
off from the living world by barriers that have never yet been crossed
from within. No change of substance, no modification of environment, no
chemistry, no electricity, nor any form of energy, nor any evolution,
can endow a single atom of the mineral world with the attribute of
life. Only by the bending down into this dead world of some living form
can these dead atoms be gifted with the properties of vitality; without
this preliminary contact with life they remain fixed in the inorganic
sphere forever.
"It is a very mysterious law which guards in this way the portals of the
living world. And if there is one thing in nature more worth pondering
for its strangeness, it is the spectacle of this vast helpless world of
the dead cut off from the living by the Law of Biogenesis, and denied
forever the possibility of resurrection within itself. The physical laws
may explain the inorganic world; the biological laws may account for the
development of the organic. But of the point where they meet,--of that
strange border-land between the dead and the living,--science is silent.
It is as if God had placed everything in earth and heaven in the hands
of nature, but had reserved a point at the genesis of life for His
direct appearing."[6]
[Footnote 6: Henry Drummond, "Natural Law in the Spiritual World,"
Chapter I.]
It would be superfluous to emphasize further this great outstanding fact
that the not-living cannot become the living by any of the processes
which we call natural; and it would be presumptuous to attempt to
emulate these eloquent words by seeking to emphasize the completeness
with which this great Law of Biogenesis confirms the truth of a real
Creation; for the supreme grandeur and importance of this law could be
only obscured by so doing.
II
Perhaps some of the most impressive lessons on this subject will be
found in connection with the history of the discovery of this great Law
of Biogenesis, which says that life can come only from life. For by
studying the history of the way in which this great Law has been
established, we cannot fail to be impressed with the thought that back
of all the complex array of living forms in our modern world which go on
perpetuating themselves in orderly ways according to natural law, they
could have originated only by a direct and real Creation, essentially
and radically different from any processes now going on.
The wisest of the ancients in Greece and Rome knew nothing of this great
law as we now know it. Aristotle, the embodiment of all that the ancient
world knew of natural science, expressly taught that the lower forms of
animals, such as fleas and worms, even mice and frogs, sprang up
spontaneously from the moist earth. "All dry bodies," he declared,
"which become damp, and all damp bodies which are dried, engender animal
life." According to Vergil, bees are produced from the putrifying
entrails of a young bull. Such were the teachings of all the Greeks and
Romans, even of the scientists of the post-Reformation period, some of
whom had accumulated a very considerable stock of knowledge concerning
plants and animals.
And similar absurdities continued to be taught until comparatively
modern times. Van Helmont, a celebrated alchemist physician who
flourished during the brilliant reign of Louis XIV, wrote: "The smells
which arise from the bottom of morasses produce frogs, slugs, leeches,
grasses, and other things." As a recipe for producing a pot of mice
offhand, he says that the only thing necessary is partly to fill a
vessel with corn and plug up the mouth of the vessel with an old dirty
shirt. In about twenty-one days, the ferment arising from the dirty
shirt reacting with the odor from the corn will effect the transmutation
of the wheat into mice. The doctor solemnly assures us that he himself
had witnessed this wonderful fact, and continues, "The mice are born
full-grown; there are both males and females. To reproduce the species
it suffices to pair them."
"Scoop out a hole in a brick," he says further, "put into it some sweet
basil, crushed, lay a second brick upon the first so that the hole may
be completely covered. Expose the two bricks to the sun, and at the end
of a few days the smell of the sweet basil, acting as a ferment, will
change the herb into real scorpions."[7]
[Footnote 7: "Louis Pasteur, His Life and Labors," p. 89.]
Sir Thomas Browne, the famous author of "Religio Medici," had expressed
a doubt as to whether mice may be bred by putrifaction; but another
scientist, Alexander Ross, disposed of this suggestion by the following
line of argument which was supposed to be conclusive as a _reductio ad
absurdum_:
"So may he (Sir Thomas Browne) doubt whether in cheese and timber worms
are generated; or if beetles and wasps in cows' dung; or if butterflies,
locusts, grasshoppers, shell-fish, snails, eels, and such like, be
procreated of putrid matter, which is apt to receive the form of that
creature to which it is by formative power disposed. To question this is
to question reason, sense and experience. If he doubts this let him go
to Egypt, and there he will find the fields swarming with mice, begot of
the mud of Nylus, to the great calamity of the in-habitants."[8]
[Footnote 8: Encyclopaedia Britannica, Vol. I, p. 64.]
When we remember that such nonsense constituted the wisdom of the
scientific world only about two centuries ago, we begin to realize the
fact that the doctrine of Biogenesis is indeed a very modern doctrine.
But it may be well to ask in passing, How could the people of former
ages understand or appreciate the great truth of Creation as we moderns
are able to do?
The first important step toward the refutation of this old pagan
doctrine of spontaneous generation was made by the Italian, Redi, in
1668. He noticed that flies are always present around decomposing meat
before the appearance of maggots, and he devised an experiment to keep
the flies away from actual contact with the meat. The meat putrified as
usual, but did not breed maggots; while the same kind of meat exposed
in open jars swarmed with them. He next placed some meat in a jar with
some wire gauze over the top. The flies were attracted by the smell of
the meat as usual, but could not reach the meat. Instead they laid their
eggs upon the gauze, where they hatched in due time, while no maggots
were generated in the meat. Thus from this time onward it became
gradually understood that, at least in the case of all the larger and
higher forms of life, Harvey's dictum, as announced some years
previously, was true, and that life comes only from life.
But the invention of the microscope opened the way for a renewal of the
controversy regarding the origin of life. Bacteria were discovered in
1683; and it was soon observed that no precautions with screens or other
stoppers could prevent bacteria and other low organisms from breeding in
myriads in every kind of organic matter. Here apparently was an entirely
new foundation for the doctrine of spontaneous generation. It was freely
admitted that all the higher forms of life arise only by process of
natural generation from others of their own kind; but did not these
microscopic organisms prove that there was "a perpetual abiogenetic
fount by which the first steps in the evolution of living organisms
continued to arise, under suitable conditions, from inorganic
matter"?[9]
[Footnote 9: Encyclopaedia Britannica, Vol. I, p. 64.]
The famous "barnacle-geese" ought not to be omitted from any sketch of
the vicissitudes of this doctrine of Biogenesis. An elaborate
illustrated account covering their alleged natural history was printed
in one of the early volumes of the Royal Society of London. Buds of a
particular tree growing near the sea were described as producing
barnacles, and these falling into the water were alleged to be
transmuted into geese. Nor should we omit mention of Huxley's _Bathybius
Haeckelii_, a slimy substance supposed to exist in great masses in the
depths of the ocean and to consist of undifferentiated protoplasm, the
exhaustless fountain from which all other forms of life had been
derived. Not long after Huxley had given it a formal scientific name in
1868, it was discovered to be merely a precipitate of gypsum thrown down
from sea water by alcohol, and thus a product of clumsy manipulation in
the laboratory, instead of a natural product of the deep sea. The
disappointment of those opposing biogenesis was severe; but the lesson
is still of value to the world to-day.
The masterly work of Tyndall and Louis Pasteur in doing for the bacteria
and protozoa what Redi had done for the larger organisms, is too much a
matter of modern contemporary history to need recital here. Upon this
great truth of life only from life is based all the recent advances in
the treatment and prevention of germ diseases and all the triumphs of
modern surgery. The housewife puts up canned fruit with the utmost
confidence because she believes in this great Law of Biogenesis. It is
because we all believe in it that we use antiseptics and fumigators and
fly screens.
III
But what are the lessons to be learned from this great fact, and what
bearing has this fact on the old Bible doctrine of a literal Creation?
Life comes now only from preexisting life. But at some time there was no
life on the globe. It does not take any great exercise of "philosophic
faith," as Huxley suggested, "to look beyond the abyss of geologically
recorded time" and recognize that at this beginning of things there must
have taken place a most wonderful event, essentially and radically
different from anything now going on, namely, the beginning of organic
life. But would not this be a real Creation in the old-fashioned sense
of this term? We cannot avoid this conclusion; nor is there anything in
either science or philosophy to indicate that this creation of the
living from the not-living was confined to _one mere speck_ of
protoplasm. It is absolutely certain that it required a real Creation to
produce life from the not-living at all; and it is just as reasonable
that this exercise of creative power may have taken place _in all parts
of the earth at the same general time_, as the Bible teaches. For if a
Being saw fit to create life at all, why should He stop with one or two
bits of protoplasmic units? An architect who can make his own bricks and
other building material, can surely build what he desires out of these
materials. Common sense tells us that, if the Creator really created
life in the beginning, He did not stop with a few specks of protoplasm
here and there over the earth. The ability to create life from the
not-living implies the ability to make full-grown trees or birds or
beasts in twenty-four hours, instead of waiting for months or years, as
is usual at the present time.
As we have already found regarding matter and energy, so of life. The
record in Genesis is confirmed, for modern science compels us to believe
in Creation as the only possible origin of life,--a Creation entirely
different from anything now going on, and one that can never be made to
fit into any scheme of uniformitarian evolution.
IV
THE CELL AND THE LESSONS IT TEACHES
I
With his usual vigor and expressiveness Henry Drummond has given us a
picture of the remarkable fact that the cells of all plants and animals
are strikingly alike, especially the single cells from which all
originate. It is easy for any one to distinguish between an oak, a palm
tree, and a lichen, while a botanist will have elaborate scientific
distinctions which he can discern between them. "But if the first young
germs of these three plants are placed before him," says Drummond, and
the botanist is called upon to define the difference, "he finds it
impossible. He cannot even say which is which. Examined under the
highest powers of the microscope, they yield no clue. Analyzed by the
chemist, with all the appliances of his laboratory, they keep their
secret.
"The same experiment can be tried with the embryos of animals. Take the
ovule of the worm, the eagle, the elephant, and of man himself. Let the
most skilled observer apply the most searching tests to distinguish the
one from the other, and he will fail.
"But there is something more surprising still. Compare next the two
sets of germs, the vegetable and the animal, and there is no shade of
difference. Oak and palm, worm and man, all start in life together. No
matter into what strangely different forms they may afterwards develop,
no matter whether they are to live on sea or land, creep or fly, swim or
walk, think or vegetate,--in the embryo, as it first meets the eye of
science, they are indistinguishable. The apple which fell in Newton's
garden, Newton's dog Diamond, and Newton himself, began life at the same
point."[10]
In these remarks, of course, Drummond is dealing with the unicellular
primal form, "as it first meets the eye of science"; and while certain
slight peculiarities (such as the constant number of chromosomes) have
been detected as characteristic of the cells of certain forms, yet for
all practical purposes these words of Drummond are just as true to-day
as when first written. Possibly it is because of a failure in our
technique or from a lack of power in our microscopes that these
wonderful protoplasmic units from which all living things originate seem
identical. But it is equally possible that they _are really identical_
in structure and in chemical composition, and that only the ever present
watchcare of the great Author of nature directs the one to develop in a
certain manner, "after its kind," and another in still another manner,
"after its kind." At any rate, the _protoplasm_ of which they are all
alike composed _is_ identical wherever found, so far as any scientific
tests have yet been able to determine.
[Footnote 10: "Natural Law," Chapter X.]
II
There are many varieties of single cells known to science which maintain
an independent individual existence. Among the unicellular plants are
the bacteria, while the unicellular animals are known as the protozoa.
And although perhaps I ought to apologize to the reader for seeming to
anticipate here a part of the discussion of the problem of "species,"
yet it seems necessary to say a few words here regarding the
"persistence" of these unicellular forms.
Among the diseases which have been proved to be due to protozoa are
malaria, amoebic dysentery, and syphilis; while among the much larger
number which are due to bacteria, bacilli, or other vegetable parasites,
are cholera, typhoid fever, the plague, pneumonia, diphtheria,
tuberculosis, and leprosy.
One of the difficulties attending the study of "species" among the
higher forms of plants and animals has always been the length of time
required to obtain any large number of generations on which to make
observations. In the case of such plants as peas, wheat, corn, or indeed
almost any form of plant life, it is only with difficulty that more than
one generation a year can be obtained; and when two or more generations
a year are produced, they are produced under more or less unnatural
conditions. So that it takes almost a lifetime carefully to test and
record in a thoroughly scientific way the results of any extensive
experiments regarding variation and heredity.
In the case of mice or rats or rabbits or guinea pigs, many more
generations can be obtained in a few years; but in the case of the
larger kinds of animals the time taken for development to maturity and
for gestation is often much prolonged; and scientific observation of an
exact character has been in vogue for so short a time that there has
always been the chance for advocates of evolution to take refuge under
the plea that, if we only had longer and more carefully conducted
observations, we could really see species in the making, one form
becoming transformed into a distinct form, or perhaps giving rise to
another and distinct form as an offshoot.
But in the case of the bacteria and protozoa, we can have a new
generation every hour or so, sometimes every half hour. True, these
forms of minute life have been under observation for only a few years;
but their _effects_ have in many cases been observed for almost the
entire length of human history. No physician would tolerate the
suggestion that the bacillus of cholera can produce the symptoms of
diphtheria, or the tubercle bacillus produce the symptoms of leprosy.
Nor will any scientist deny that such diseases as the plague,
tuberculosis, or diphtheria are identical with diseases which ravaged
Rome or Greece or Egypt thousands of years ago. And as the symptoms of
these modern diseases are similar to those recorded by acute observers
in Greece or Egypt two thousand years or more ago, we must conclude that
the organisms causing these symptoms are doubtless identical. Similar
remarks might be made regarding fermentation and other forms of decay.
In the case of a form of bacteria which reaches maturity and redivides
in half an hour, the number of individual forms existing at the end of
two days would need about twenty-eight figures to represent it.
Doubtless these forms never multiply at this rate uninterruptedly for
any great length of time, or else they would occupy the whole world to
the exclusion of every other form of life. And doubtless instances arise
where the period of growth to maturity and division is prolonged to
several times the half-hour period mentioned above. But in any case, as
we contemplate the length of time during which such well marked diseases
as diphtheria, leprosy, or the plague have been known, we must
acknowledge that these unicellular forms seem to _breed true_ during a
most astonishingly long period. How can we deny that this "persistence"
of these unicellular forms constitutes a very strong argument in favor
of the "fixity" of these forms?
III
But we must proceed to examine the behavior of the various kinds of
cells of which the various multicellular organisms are composed.
Plants were known to be composed of cells, and their cells were studied
and described some years before it was understood that animals also are
composed of cells as units. Even then, however, the first propounders of
the cell theory (Schleiden and Schwann) had no clear or accurate idea of
the origin of cells, or of their essential characters and structure. As
to origin, they supposed that cells arose by a sort of crystallization
from a mother liquor; and as to structure, they looked upon the
cell-wall as the really important part, the fluid contents being quite
subordinate. Hugo von Mohl (1846) applied to the fluid contents of the
cell the term "protoplasm," and Max Schultze (1861) showed that this
protoplasm is really identical in all organisms, plants and animals,
also that the cell-wall is frequently absent in many animal tissues and
in many unicellular forms, indicating that the protoplasm is the really
important substance. By this time also it had become known that cells
never arise _de novo_, as had been supposed by the earlier
investigators, but that cells arise only by division of preexisting
cells; or as Rudolf Virchow (1858) expressed it, "_omnis cellula e
cellul[=a]._"
It was, however, many years before the details of the growth and
reproduction of the cells (cell-division) became well understood. Not
until the last quarter of the nineteenth century was it settled that the
nucleus of the cell is also a supremely important part; but finally in
1882 Flemming was able to extend Virchow's aphorism to the nucleus also:
_omnis nucleus e nucleo_.
Since these discoveries our knowledge of the methods of cell-division
has much increased; and in the light of our modern knowledge of these
matters there is nothing in all nature more marvellous than the regular
orderly way in which cells reproduce themselves according to fixed laws.
Certain cells in the developing embryo, for example, are early set apart
for a particular function or for building certain structures, and
thereafter are never diverted from this duty so as to do a different
work or produce a different kind of structure. In the young embryo
certain structures arise at certain predestined times in particular
places, and only there and out of these cells alone. As to _why_ it
should be so, we cannot tell, save as the result of deliberate design
and as an expression of the order-loving mind of the God of nature. In
the words of one of the greatest of modern authorities, "We still do not
know why a certain cell becomes a gland-cell, another a gangleon-cell;
why one cell gives rise to smooth muscle-fiber, while a neighbor forms
voluntary muscle.... It is daily becoming more apparent that epigenesis
with the three layers of the germ furnishes no explanation of
developmental phenomena."[11]
[Footnote 11: _Nature,_ May 23, 1901.]
In accordance with the general principle of a division of labor, certain
cells become early set apart to particular functions, and in accordance
with the varying demands of these functions the developing cells may
become greatly changed in form and in vital characteristics. That is,
one cell specializes, let us say, in secretion, another in
contractility, another in receiving and carrying stimuli, etc. In this
way we will have the gland-cell, the muscle-cell, and the nerve-cell,
each cell destined to produce one of these organs developing others
"after its kind," the result being that it is soon surrounded with
numerous companions doing a similar work, making up in this way a
particular tissue or organ--gland, muscle, or nerve--which in the
aggregate has for its function the work of the particular cells
composing it.
But the important thing for us to remember in this connection is that
when cells once become thus differentiated off and dedicated to any
particular function, _they can never grow or develop into any distinctly
different type of cell with other and different functions_. It is true
that through pathologic degeneration the form and even the function of
cells may become greatly changed; but never does it amount to a complete
metamorphosis or complete transformation into another distinctly
different type.
This is a very important principle, and it contains so many lessons for
us bearing on the philosophy of life in general that it may be allowable
to establish this fact by several somewhat lengthy quotations from
standard authorities.
The first will be from one of the highest authorities on embryology,
Charles Sedgwick Minot, of Harvard:
"In accordance with this law [of differentiation] we encounter no
instances, _either in normal or pathological development_, of the
transformation of a cell of one kind of tissue into a cell of another
kind of tissue; and further we encounter no instances of a
differentiated cell being transformed back into an undifferentiated cell
of the embryonic type with varied potentialities."[12]
Again, we have the following from one of the foremost pathologists, as
to the strict and rather narrow limits of even pathologic change:
"Epithelium and gland cells ... never become converted into bone or
cartilage, or vice versa; while, again, it may be laid down that among
epiblastic and hypoblastic tissues, on the one hand, and mesoblastic
tissues on the other, there is no new development or _metaplasia_ of the
most highly specialized tissues from less specialized tissues; a simple
epithelium cannot in the vertebrate give rise to more complex glandular
tissue, or to nerve cells; in regeneration of epithelium there is no new
formation of hair roots or cutaneous glands. The cells of white fibrous
connective tissue have not been seen to form striated or even
non-striated muscle."[13]
[Footnote 12: _Science_, March 29, 1901, p. 490.]
[Footnote 13: J.G. Adami, "Principles of Pathology," pp. 641-642.]
As implied by these quotations, a constant and progressive
differentiation of cells prevails in the developing embryo; and when
complete, certain groups of cells act as specialists in doing only
certain kinds of work for the body. These cells maintain their specific
characters in a very remarkable degree under normal conditions. Under
various abnormal conditions, however, these cells may become modified as
to functions, so that cells or tissues of one type may assume more or
less completely the characters of another type. "But," as a very high
authority declares, "the limitations in this change in type are strictly
drawn, so that one type can assume only the characters of another which
is closely related to it. This change of one form of closely related
tissue into another is called _metaplasia_....
"When differentiation has advanced so that such distinct types of tissue
have been formed as connective tissue, epithelium, muscle, nerve, _these
do not again merge through metaplasia. There is no evidence that
mesoblastic tissues can be converted into those of the epiblastic or
hypoblastic type, or vice versa_."[14]
[Footnote 14: Delafield and Prudden, "Text-Book of Pathology," pp. 62,
63.]
This modification of function among the cells which sometimes goes on in
the developing embryo, or under pathologic conditions, is very closely
analogous to the variation which goes on among species of animals and
plants. But, as we shall see later, there is a well marked limit to this
variation among species, just as we see there is in the variations among
the cells. Practically the same general laws hold good in each case.
If cells did not maintain their ancestral characters in a very
remarkable way, what would be the use of grafting a good kind of fruit
onto a stock of poorer quality? The very permanency of the grafts thus
produced is proof of the persistency with which cells reproduce only
"after their kind."
IV
How can we fail to see the bearings of these facts on the doctrine of
the transformation of species among ordinary plants and animals, which
are merely isolated and self-contained groups of cells? Do not these
facts constitute strong presumptive evidence that among animals and
plants, though there may be variation in plenty within certain limits,
perhaps within even much wider limits than used to be thought possible,
yet among these distinct organisms, little and big, new forms develop
only after their ancestral type, in full accord with the record given in
the first chapter of the Bible?
But we are now prepared to examine in more detail the facts as now known
to modern science regarding "species" of plants and animals.
V
WHAT IS A "SPECIES"?
I
We have seen that there is no way to account for the origin of matter,
of energy, or of life, except by postulating a real Creation.
We have seen that cells continue to maintain their identity, and
reproduce only "after their kind."
We must now deal with the higher forms of cell aggregates, which we call
plants and animals. It has long been held that these at least are
mutable, that one kind of plant or of animal may in the course of ages
be transformed into a distinctly different type; and of late years there
has accumulated a very voluminous literature dealing with the various
intricacies of this problem of the origin of species. How can we deal
with such a large subject in a brief way? It seems best to confine our
attention in this chapter to an attempt to answer the question, What is
a species? and are "species" natural groups clearly delimited by nature?
II
The term "species" was at first used very loosely by scientific writers.
It meant very little more than our vague word _kind_ does at the
present time. Not until the time of Linnaeus (1707-1778) did the term
acquire a definite and precise meaning. The aphorism of the great
botanist, "_species tot sunt diversae quot diversae formae ab initio sunt
creatae_"--"just so many species are to be reckoned as there were forms
created in the beginning,"--was at least an attempt to use the term in a
well-defined sense. Of course, this definition assumed the "fixity" of
species; but with the wide prevalence of the views of Darwin and his
followers the term "species" has fallen into disrepute, and is now
regarded by many as only an artificial rank in classification
corresponding to no objective reality in the natural world. Some
writers, as Lankester, have found so much fault with the term as to urge
its complete abandonment in scientific literature. This is logical
enough from the standpoint of Darwinism; for if the latter be true there
ought indeed to be such a swamping of every incipient "species" as to
make one kind blend with others all around it in the classification
series.
But since the term has by no means been discarded, we must endeavor to
determine the sense in which it continues to be used in good scientific
literature.
"A species," says Huxley, "is the smallest group to which distinct and
invariable characters can be assigned." The Standard Dictionary says
that the term is used for "a classificatory group of animals or plants
subordinate to a genus, and having members that differ among themselves
only in minor details of proportion and color, and are capable of
fertile interbreeding indefinitely."
The latter authority also adds:
"In the kingdoms of organic nature species is founded on identity of
form and structure, and specifically characterized by the power of the
individuals to produce beings like themselves, who are in turn
productive."
To put the matter still more definitely before the reader, we quote the
following from a well-known scientist whose writings on the subject of
evolution have had a wide circulation:
"There are two bases on which species may be founded. Species may be
based on _form_, morphological species; or they may be based on
_reproductive functions_, physiological species. By the one method a
certain amount of difference of form, structure, and habit, constitutes
species; according to the other, if the two kinds breed freely with each
other and the offspring is indefinitely fertile, the kinds are called
varieties, but if they do not they are called species."[15]
This author adds that this physiological test, as to whether or not the
kinds are cross fertile, "is regarded as a most important test of true
species, as contrasted with varieties or races."
[Footnote 15: Joseph Le Conte, "Evolution and Religious Thought," p.
233.]
III
When we look at the matter in this light, it is very evident that there
are multitudes of long recognized specific distinctions that ought to
be discarded. For instance, there are some twenty odd "species" of wild
pigs scattered over the Old World, which Flower and Lydekker assure us
would probably "breed freely together."[16] The yak and the zebu of
India, and the bison of America, would on this basis have to be
surrendered, for it is well known that they will all breed freely with
the common domestic cattle, as well as with one another. Perhaps all or
nearly all of the dozen or more "species" of the genus _Bos_ would thus
be included together. All of the dogs, wolves, and others of the
_Canidae_ might thus be considered as fundamentally a unit. The cats
(_Felidae_) are well known to breed freely together, Karl Hagenbeck of
Hamburg having crossed lions and tigers as well as others of the family.
Practically all of the bears have been crossed repeatedly, and the
progeny of these and other crosses are quite familiar sights at the
London Zooelogical Gardens. Among the lower forms of life even more
surprising results have been attained by Thomas Hunt Morgan and others.
[Footnote 16: "Mammals Living and Extinct," pp. 284-285.]
It would, however, be a very hasty conclusion to say on the basis of
these facts that there are no natural limitations to groups of animals
and plants. But we are entirely warranted in concluding from these facts
that in very many cases, perhaps in most, our system of taxonomic
classification of animals and plants has gone altogether too far, and
that scientists have erected specific distinctions which are wholly
uncalled for and which confuse and obscure the main issues of the
species problem. Among the workers in botany and in every department of
zooelogy there have always been the "splitters" and the "lumpers," as
they are familiarly called; the former insisting on the most minute
distinctions between their "species," thus multiplying them; the latter
being more liberal and tending to diminish the number of species in any
given group. For a generation or more in the recent past the "splitters"
had things pretty much their own way; but of late there is a growing
tendency to frown down the mania for creating new names. Even yet it is
with the utmost reluctance that long established specific distinctions
are surrendered, as is illustrated in the case of the mammoth, which is
acknowledged by some of the very best authorities to be really
indistinguishable from the modern Asiatic elephant. Several fossil bears
were long listed in scientific books; but they are all acknowledged now
to be identical with the modern grizzly, and as we have already
intimated all the modern ones ought to be put together. These modern
rationalizing methods have made but a slight impression on the vast
complex of the fossil plants and animals, affecting the names of only a
few of the larger and better known forms. In the realm of invertebrate
palaeontology, however, the "splitters" are still holding high carnival,
in spite of the efforts of some very prominent scientists in the
opposite direction. For palaeontologists still follow the irrational
course of inventing a new name, specific or even generic, for a form
that happens to be found in a kind of rock widely separated as to "age"
from the other beds where similar forms are accustomed to be found. As
Angelo Heilprin expresses it, "It is practically certain that numerous
forms of life, exhibiting no distinctive characters of their own, are
constituted into distinct species _for no other reason than that they
occur in formations widely separated from those holding their nearest
kin_."[17]
As a result of these methods this same author declares: "It is by no
means improbable that many of the older _genera_, now recognized as
distinct by reason of our imperfect knowledge concerning their true
relationships, have in reality representatives living in the modern
seas."[18]
[Footnote 17: "Geographical and Geological Distribution of Animals," pp.
183, 184.]
[Footnote 18: _Id_., pp. 207, 208.]
But the situation is very little better when we come to deal with plants
and animals of our modern world. Because, with the many thousands of
students of natural science all over the world, each anxious to get into
print as the discoverer of some new form, the systematists have a dead
weight of names on their hands that by a rational and enlightened
revision could doubtless be reduced to but a fraction of their present
disheartening array. For as the result of the extensive breeding
experiments now being carried on under the study of what is called
Mendelism (a term that will be explained in the next chapter), it has
been found that great numbers of the "species" of the systematists or
classificationists will not stand the physiological test of breeding,
that is, they are found to breed freely together according to the
Mendelian Law. As William Bateson remarks:
"We may even be certain that numbers of excellent species recognized by
entomologists or ornithologists, for example, would, if subjected to
breeding tests, be immediately proved to be _analytical varieties_,
differing from each other merely in the presence or absence of definite
factors."[19]
The following from David Starr Jordan, the leading American authority on
fishes, will serve to show how numerous have been the new names invented
in recent years, all tending further to confuse and complicate the
problem of what is a species:
"In our fresh-water fishes, each species on an average has been
described as _new_ from three to four times, on account of minor
variations, real or supposed. In Europe, where the fishes have been
studied longer and by more different men, upwards of six or eight
nominal species have been described for each one that is now considered
distinct."[20]
[Footnote 19: "Mendel's Principles of Heredity," p. 284, 1909.]
[Footnote 20: "Science Sketches," p. 99.]
And again:
"Thus the common Channel Catfish of our rivers has been described as a
new species not less than _twenty-five times_, on account of
differences real or imaginary, but comparatively trifling in value."[21]
[Footnote 21: "Science Sketches," p. 96.]
Perhaps the reader will tolerate another somewhat long quotation because
of the light which it sheds on this whole problem.
"Some years ago we had a parasite of a very destructive aphid down in
our books as _Lysiphlebus tritici_. In carrying out our investigations
it became necessary to find out whether this parasite had more than a
single host insect, and whether it could develop in more than one
species of aphid. To this end, recently emerged males and females were
allowed to pair, after which the female oviposited in several species of
aphids. Both parents were then killed and preserved and all of their
progeny not used in further experiments were also preserved, and thus
entire broods or families were kept together. In this way females were
reared out of one host species and allowed to oviposit in others, until,
often after several hosts had been employed, it would be bred back into
the species whence it first originated. In all cases the host was reared
from the moment of birth, while with the parasite both parents and
offspring were kept together.
"The result of this little fragment of work _was to send two genera and
fourteen species to the cemetery_--you may call it Mt. Synonym Cemetery,
if you choose--while the insect involved is now _Aphidius testaceipes_.
The systematist who studies only dried corpses will soon be out of
date."[22]
[Footnote 22: F.M. Webster, of the U.S. Dept. of Agriculture, in
_Science_, April 12, 1912, p. 565.]
IV
Now all this is not given to intimate that there is no scientific
justification for the term "species," but to make plain to my
non-professional readers what every well-informed biologist already
knows, namely, that at the present time the "species question" is still
in a very unsatisfactory state. The facts given above would strongly
suggest that there probably is indeed such a thing as a species, in the
sense assigned by Linnaeus, who as we have seen wished to make it a
designation covering all the descendants of each distinct kind
originally created. But this original aim of Linnaeus is to-day not
merely ignored but treated with lofty contempt; for according to the
prevailing theories of evolution, all the manifold diversities of life
in our modern world have come about gradually as the result of a slow
development by natural process, and hence it would be vain beyond
measure to attempt to determine the limits of a "species" in the sense
understood by Linnaeus.
But we may conclude, from the facts presented above, that if there is
such a naturally delimited group as a "species" in the Linnaean sense of
the word, it by no means coincides with what now passes under this name,
but might include many so-called species, often a whole genus, or even
several.
With this in mind, we must pass on to consider the next step in our
study, as to whether new "species" are now coming into being in our
modern world under scientific observation, either natural or
artificial.
VI
MENDELISM AND THE ORIGIN OF SPECIES
"Had Mendel's work come into the hands of Darwin, it is not too much to
say that the history of the development of evolutionary philosophy would
have been very different from that which we have witnessed."[23]
[Footnote 23: William Bateson, "Mendel's Principles of Heredity," p.
316.]
I
From the latter part of the eighteenth century, attempts were
continually being made to explain the origin of all organic forms by
some system of development or evolution. Buffon had dwelt on the
modifications directly induced by the environment. Lamarck had made much
use of this idea, claiming that such modifications were transmitted to
posterity, and claiming the same for the structural changes produced by
use and disuse. Lamarck's work did not become at all popular while he
lived, chiefly through the overpowering influence of Baron Cuvier, who
had an equally fantastic scheme of his own, which may well be termed a
burlesque on Creation and in which an extreme fixity of "species" was a
cardinal doctrine. Erasmus Darwin and Robert Chambers in England also
tried to make a theory of evolution believable; though their efforts
were but little more successful in gaining the ear of the world.
But to all that had gone before Charles Darwin and A.R. Wallace (1858)
added the idea of "natural selection," or "the struggle for existence,"
to use the respective terms coined by each of these authors, as the
chief means by which the effects of variation are accumulated and
perpetuated so as to build up the modern complexities of the plant and
animal kingdoms. Partly because it was a psychological moment, from the
fact that the uniformitarian geology of Lyell with its graded advance of
existences from age to age seemed absolutely to demand some evolutionary
explanation; partly because artificial selection was a familiar idea of
proved value in selective breeding, and "natural selection" seemed an
exact parallel carried on by nature in the direction of continual
improvement; but perhaps more largely because the abstract idea of
"natural selection" involved so many intricate separate concepts that
for nearly a generation scarcely two naturalists in the world could
state the whole problem of the theory exactly alike;--on all these
accounts the theory of natural selection, or of the "survival of the
fittest," to use the phrase of Herbert Spencer, became in the latter
decades of the nineteenth century well-nigh universal.
But about 1887 a faction or school arose who criticized the main idea of
Darwin and Wallace and fell back on the Lamarckian factor of the
transmission of acquired characters as really the essential cause of
the process of evolution. Herbert Spencer, E.D. Cope and others did much
to criticize natural selection as inadequate to do what was attributed
to it, dwelling on the importance of the transmission of acquired
characters. Spencer even went so far as to declare, "either there has
been inheritance of acquired characters, or there has been no
evolution." These Neo-Lamarckians argued that natural selection alone
can neither explain the origin of varieties, nor the first steps in the
slow advance toward "usefulness." An organ must be already useful before
natural selection can take hold of it to improve it. Selection cannot
make a thing useful to start with, but only (possibly) make more useful
what already exists. Until the newly formed buds of developing limbs or
organs became decidedly "useful" to the individual or the species, would
they not be in the way, merely so many hindrances, to be removed by
natural selection instead of being preserved and improved? But, in this
view of the matter, they argued, what single organ of any species would
there be that must not thus have appeared long before it was wanted?
Or to use the pungent words quoted with approval by Hugo de Vries at the
end of his "Species and Varieties" (pp. 825, 826), "Natural selection
may explain the survival of the fittest, but it cannot explain the
arrival of the fittest."
This side of the argument is dwelt upon at some length by Alex. Graham
Bell, as reported in a recent interview. He says:
"Natural selection does not and cannot produce new species or varieties
or cause modifications of living organisms to come into existence. On
the contrary, its sole function is to prevent evolution. In its action
it is destructive merely,--not constructive,--causing death and
extinction, not life and progression. Death cannot produce life; and
though natural selection may produce the death of the unfit, it cannot
produce the fit, far less evolve the fittest. It may permit the fit to
survive by not killing them off, if they are already in existence; but
it does not bring them into being, or produce improvement in them after
they have once appeared."[24]
[Footnote 24: _World's Work_, December, 1913, p. 177.]
Opposing these Neo-Lamarckians were such prominent scientists as August
Weismann, A.R. Wallace, E. Ray Lankester, who strenuously opposed the
idea that "acquired characters," or more precisely _parental
experience_, are ever transmissible. In the subsequent years the
greatest variety of experimental tests have been applied to secure the
hereditary transmission of any sort of such acquired characters, with
uniformly negative results. One of the most elaborate of these
experiments was conducted by a German botanist, who transplanted 2,500
different kinds of mountain plants to the lowlands, where he studied
them for several years alongside their relatives, natives of these
lowlands. He found that their mountain environment had made absolutely
no permanent change in their structures or habits, which soon conformed
exactly with those of their relatives which had lived in the lowland
environment for centuries. Many similar efforts have been made to
confirm this doctrine of the transmission of acquired characters; but
their universal failure is like that of mechanics in trying to invent
perpetual motion.
Thomas Hunt Morgan sums up the present situation in the following words:
"To-day the theory has few followers among trained investigators, but it
still has a popular vogue that is wide-spread and vociferous." And we
may add that the extent of its spread is directly proportioned to the
need felt for this doctrine as a support of the theory of evolution,
while the vociferance of its advocates is inversely proportioned to the
evidence in its support.
As a result of extensive modern experiments and discussion, biologists
have grown very cautious, and are by no means so positive as they were
twenty years ago in affirming just _how_ species have come into
existence. Echoes of this old controversy between the two leading
schools of biologists are occasionally heard; but the enthusiasm with
which they set out a half century ago to solve the riddle of plant and
animal life has largely given way to a purpose to discard speculation
and patiently to observe and record actual facts. For with natural
selection discredited in the house of its friends, and Lamarckianism
under grave suspicion from want of a single well authenticated example,
it is hard to see what there is left of the biological doctrine that
has so dominated scientific thought for a half century. If each of these
opposed schools of scientists are right in _what they deny_, the whole
theoretical foundation for the origin of new kinds of animals and plants
is swept away,--absolutely gone. For if an individual really cannot
transmit what he has acquired in his lifetime, how can he transmit what
he has not got himself, and what none of his ancestors ever had? And if
natural selection cannot start a single organ of a single type, what is
the use of discussing its supposed ability to improve them after the
machinery is all built?
II
Such was the general condition of theoretical biology about the
beginning of the present century. In the meantime those who were dealing
with the empyrical or experimental side of these problems were seeking
for the causes of and the rules for variation. All living things vary
from one generation to another; the question was, Why do they vary? and
do these variations really represent new characters comparable to new
species in the making? or are they, so to speak, but an elastic reaction
of the internal vital elasticity of the organism, all the while latent
and only seeking a favorable expression, to return again under other
conditions to the former type?
The effort to reduce these variations to law and system was pursued by
thousands of investigators, with varying but at all times perplexing
and disappointing results. But in the year 1900 the scientific world
awoke to the surprising fact that a patient obscure investigator had
already solved most of the puzzles of variation and heredity some
thirty-five years before. Gregor Mendel, born a peasant boy, trained as
a monk, and afterwards appointed Abbot of Bruenn, had in the year 1865
published the results of his experiments in breeding, which had been
ignored or forgotten until rediscovered in 1900 by de Vries and two
others simultaneously. From this point Mendelism, as it is now called,
has steadily gained ground, until at the present time it can be said to
be the dominating conception among biologists the world over regarding
the problems of heredity.
Mendel worked chiefly with peas, crossing different varieties. In his
methods of investigation he differed from all previous investigators in
concentrating his attention upon a single pair of alternative or
contrasted characters at a time, and observing how these alternative
characters are transmitted.
Thus when he crossed a tall with a dwarf, giving attention to this pair
of contrasted characters alone, he found that all the first hybrid
generation were talls, with no dwarfs and no intermediates. Accordingly
he called the tall character _dominant_, and the dwarf character
_recessive_, and a pair of contrasted characters which act in this way
are now called _factors_ or sometimes called _unit characters_. But on
allowing these hybrids to cross-fertilize one another in the usual way,
Mendel found that in the second generation of hybrids there were
_always_ _three talls to one dwarf_ out of every four. Further
experiments proved that these dwarfs of the second hybrid generation
_always bred true_, that is, one out of four; and that one out of the
remaining talls always bred true, making another quarter of the total;
while the remaining fifty per cent. proved to be mixed tails, always
acting as did the original hybrids, splitting up in the next generation
in the same arithmetical proportion as before.
Accordingly, if we confine our study to the two contrasted characters,
tallness and dwarfness, we see that just three kinds of peas exist,
namely, dwarfs which breed true, talls which breed true, and talls which
always give the same definite proportion of talls and dwarfs among their
descendants. Innumerable experiments which have since been made with
other pairs of characters have demonstrated that this same mathematical
proportion holds good throughout the whole world of plants and
animals;[25] and hence this astonishing result is now called Mendel's
Law, and is regarded as the most important discovery in biology in
several generations.
[Footnote 25: When dealing with only a few individual cases, we do not
always find them to come out in such exact proportion; but when the
number of examples is large, the proportion is so close to these figures
that the exceptions can be entirely neglected as probably due to error
of some kind.]
There are two distinct kinds of Andalusian fowls, one pure bred black,
the other pure bred white with slight dashes of black here and there.
When these are mated, no matter which color is the father or the mother,
the next or hybrid generation are always a queer mixture of black and
white called by fanciers blue. When these blues are interbred,
one-quarter of their offspring will be white, which will prove to breed
true ever afterwards, one-quarter will be black that will breed true,
and fifty per cent. will be blue which will break up in the next
generation in the very same way as before. In this case neither white
nor black character is dominant, and accordingly we have a blending of
both in the first hybrid generation.
In guinea pigs, black color has been found to be dominant over white,
rough coat over smooth coat, and short hair over long hair. These
remarkable results following from an experimental trial of Mendelism
have stimulated hosts of investigators in all parts of the world, until
now many varieties of plants and animals have been studied for many
successive generations, already, building up a considerable literature
dealing with the subject.
Perhaps the most extensive and exact series of experiments along this
line have been carried on by Thomas Hunt Morgan and his assistants, of
Columbia University. For over five years they have been breeding the
wild fruit fly (_Drosophila ampelophila_), during which time they have
originated and observed over a hundred and twenty-five new types that
breed true according to Mendel's laws. Every part of the body has been
affected by one or another of these mutations. The wings have been
shortened, or changed in shape, or made to disappear entirely. The eyes
have been changed in color or entirely eliminated. And each of these
wonderful variations was brought about not gradually, but at _a single
step_.
Professor Morgan grows justifiably sarcastic in contrasting these
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