A Century of Evolution
By Gordon H. Clark, Ph.D.
This is one of the messages delivered at Weaverville, N. C, on
August 20, 1958, on the program of the Conference on Reformed Theological Thought,
sponsored by The Southern Presbyterian Journal. Other addresses delivered on the
same date will be printed in future issues of the Journal. — Editors.
I. The Historical Background
The theory of Evolution, as initiated by the publication of Charles
Darwin's Origin of Species, has had a profound impact on the fortunes of Christianity;
and since next year, 1959, is the centenary of that publication, it is appropriate
for us at this time to audit our books and evaluate the contemporary situation.
Darwin on the voyage of the Beagle had noticed the similarities
and the differences between the foxes on the mainland and the foxes on a distant
island. They were so similar that a genetic relationship could not be denied, but
they were also so different that they constituted a new species. From this and similar
observations Darwin concluded that these species could not be explained by special
creation but must have evolved from common ancestors.
The idea of evolution was then applied to man. Homo sapiens could
not be regarded as a special creation, but must have evolved from some lower form
of life. Such attraction did the idea of evolution exert on the minds of scholars
that they soon extended it to the astronomical cosmos on the one hand and on the
other to sociological and historical phenomena. Thus there arose evolutionary accounts
of religion and the history of the Hebrews.
At many points the conflict with Christianity was obvious. The
evolution of religion from animism or fetishism and the history of the Hebrews that
makes monotheism a very late development entirely contradict the Bible and makes
special revelation impossible. Within biology the assertion that man has evolved
from lower species conflicts with the Biblical account of the creation of Adam and
especially of Eve.
Cosmic evolution was made to rule out the existence of God altogether.
For example, Corliss Lamont {Humanism as a Philosophy, p. 102) says, "Biology
has conclusively shown that man and all other forms of life were the result, not
of a supernatural act of creation by God, but of an infinitely long process of evolution...
which started with the lowly amoeba and those even simpler things marking the transition
from inanimate matter to life... Mind, in short, appeared at the present apex of
the evolutionary process and not at the beginning." Since, further, these ideas
became immensely popular, orthodox Christianity was faced with a conflict of major
proportions.
II. The First Reactions.
Faced with this attack on the inspiration of the Scriptures,
with this denial of creation, and in some instances faced with a blatant atheism,
the Christians reacted vigorously. That their reaction was not always wise is hardly
surprising. In many disputes first reactions often miss the point. For ages, from
Aristotle in antiquity to Linnaeus in the eighteenth century, the scientists
had taught the fixity of existing species. The Christians trusted the scientists
and carelessly assumed that the existing species were the several kinds which God
originally created. They did not consider the possibility that the kinds of Genesis
might be what modern biologists call families or even orders. Thus they failed to
recognize that the existing species are many more in number than the special acts
of creation listed in the first chapter of Genesis. Indeed the special acts of creation
are fewer than the contemporary status of biology seems to require; but more of
this later.
Because then the Christians were trapped into defending Linnaeus
rather than the Bible, they often made regrettable blunders. And as is usual in
free-for-all altercations the opponents publicize one's blunders in order to distract
attention from whatever is of worth. Considerable time has passed by now — a full
century — and there may be some interest in observing what remains on the field
of battle.
III. The Present Situation
For a great many people, however, there is no point in viewing
the scene of battle, if such a viewing is supposed to show some remaining balance
between the two forces. The popular opinion is that evolution won a sweeping victory
and the Bible was decisively defeated.
"Since Darwin's day," says Richard Swan Lull, Professor
of Paleontology at Yale University (Organic Evolution, p. 15; 1947) — "Since
Darwin's day evolution has been more and more generally accepted, until now in the
minds of informed thinking men there is no doubt that it is the only logical way
whereby the creation (i.e. biology) can be interpreted and understood."
William Flowells of the University of Wisconsin (Mankind So Far,
p. 5, 1944) says, "The 'theory of evolution' is an overworked term, in its
popular usage, and unfortunate besides, because it implies that, after all, there
may be something dubious about it. Evolution is a fact, like digestion... The phrase
[theory of evolution] is doubtless the expression of a diehard prejudice."
However, this is not the whole story. Even those who insist that
evolution is a fact beyond doubt betray certain hesitancies. Howells himself
admits that "there is also the mystery of how and why evolution takes place
at all... Nor is it known just why evolution occurs or exactly what guides its steps."
Professor Lull also admits, "We are not so sure, however, as to the modus operandi."
And J. Arthur Thomson makes an astounding statement:
"Many of the genealogical trees which Haeckel was so fond
of drawing have fallen to pieces. Who can say anything, except in a general way,
regarding the ancestry of birds or even Vertebrates? The Origin of Species was published
in 1859, but who today has attained clearness in regard to the origin of any single
species?"
Even Dobzhansky, who, in opposition to Thomson, would claim that
he has attained clarity in regard to the origin of many species, admits, with respect
to the human species, that "we have only the most fragmentary information concerning
the stages through which the process has passed" (Evolution, Genetics, and
Man, p. 319, 1955).
If thus Dobzhansky admits less than Thomson, Howells is even
more dogmatic than Dobzhansky, for Howells asserts that the human line can in fact
be traced back to the fishes (op. cit. p. 5) .
Here then are various claims and admissions. What is their significance?
Perhaps after all there is some reason for reviewing the debris of battle.
IV. Significance of Concessions.
An attempt to evaluate such concessions as these may begin with
some more material from J. Arthur Thompson. Professor Thompson is a convinced evolutionist.
In his volume Concerning Evolution (pp. 44-48) he treats very seriously the idea
that life originated from nonliving matter. He even suggests that this process is
still going on. We may believe it is still going on because we are not sure that
it is not going on. But if perchance life is not now originating from inanimate
matter, perhaps the sun's rays and the earth's atmosphere were quite different long
ago and produced results then which they cannot produce now.
Dobzhansky also, as well as Thomson, seems to accept the notion
that life originated from non-living matter. He admits at first that this is only
a conjecture, and that it is highly improbable; but then he concludes that "a
highly improbable event may, however, take place somewhere in the universe. Such
a 'lucky hit' happened to occur on a small planet, earth" (op. cit. p. 19).
Thus he states the spontaneous generation of life as a fact.
In anticipation of the discussion of the philosophy of science
that is to follow, something needs to be said here with respect to the origin of
life from non-living matter. Is there any evidence of this? Is there sufficient
evidence to assert point blank that it happened? It is a mere tautology to say that
if certain conditions obtained in the past, certain effects could have occurred.
But the important question is not: Could such and such have happened, if the conditions
were right? The important question is: Were the conditions right and did such and
such things actually happen?
Now, if the evolutionist must be so dogmatic on the origin of
life, how can he afford to repudiate Haeckel's genealogical trees or admit doubt
as to the origin of species?
The explanation, as Thomson gives it, is as follows: "Uncertainty
in regard to the factors cannot be said to affect the validity of the modal concept
of evolution, and it is entirely unfair to use confessions of ignorance in regard
to the factors as if they implied doubt in regard to the fact... There is not the
slightest reason for jettisoning the modal formula because we are still very ignorant
in regard to the detailed steps and factors in the process" (Op. cit. p. 100).
Similarly Professor Lull, after admitting that "We are not
so sure, however, as to the modus operandi," adds immediately "but we
may rest assured that the process has been in accordance with great natural laws,
some of which are as yet unknown, perhaps unknowable" (Organic Evolution, p.
15) .
V. A Lesson from Physics
The point I now wish to examine is whether or not a sound philosophy
of science will permit us to rest assured with a theory whose factors are unknown
and perhaps unknowable. If we examine scientific method as practiced by the physicists,
their superiority in ideals of caution, accuracy, and rigor will become obvious.
The theory, or better, the theories of light can serve as a well known example.
Sir Isaac Newton (1642-1727) believed that light consists of
small particles or corpuscles. This he believed chiefly on the basis that the corpuscular
theory best explains the rectilinear propagation of light. In addition to this hypothesis,
there also existed in Newton's day a theory that considered light to be a wave motion
of a fluid medium; but it took some juggling to make this theory suitable for rectilinear
propagation. Newton did not approve of the juggling.
Now, the corpuscular theory implies that the speed of light in
water is greater than the speed of light in air. On the other hand, the wave theory
of light implies that the speed of light in air is greater than the speed of light
in water. Unfortunately there was no method, throughout the eighteenth century,
by which the speed of light could be experimentally measured. That is to say, the
factors, to use Professor Thomson's language, were unknown and unverifiable. But
instead of blindly declaring one of these theories a fact despite the ignorance
of the factors, the best scientific reaction during the first half of the nineteenth
century was a search for some method of discovering the factors. Eventually a method
was invented and in 1850 Leon Foucault performed the experiment. By this experiment
Foucault determined that the speed of light is greater in air than in water.
At this point Foucault showed a scientific caution that might
still be emulated. He might have concluded that his experiment had demonstrated
the wave theory. But he actually concluded that his experiment had refuted the corpuscular
theory. The experiment makes the wave theory possible, and since no other theory
had been suggested, scientists would naturally use the wave theory. Yet other theories
then undreamed of might later be invented. These later theories must be better.
Hence Foucault concluded only that the corpuscular theory is false and the wave
theory is possible. And this conclusion came by attention to the mechanics, the
modus operandi, the factors in the case.
However, even Foucault's caution was too bold. In 1902 another
important experiment was conducted. If light is a wave motion, the intensity of
light gradually diminishes as the source becomes more and more distant. This diminishing
continuously approaches zero. But if light is corpuscular, another implication follows.
Suppose a metal plate is slowly made to recede from a source of light. If light
is corpuscular, fewer and fewer particles hit the plate. At a given distance only
one particle will hit the plate. Beyond that distance the intensity will be zero.
That is to say, instead of the intensity decreasing continuously to zero, it will
decrease to one and then suddenly drop to zero. The experiment showed that the intensity
actually drops suddenly from one to zero. Therefore light cannot be a wave motion;
it must be corpuscular in spite of Foucault's experiment which showed it could not
be corpuscular. What is worse, this result is in contradiction to the fundamental
laws of the electromagnetic field.
Now, it is not my purpose to lecture on the physics of light,
but rather to point up the philosophy of science. Proper scientific ideals require
the scientist to consider the possibility of alternate hypotheses. He can never
accept any hypothesis as final and beyond doubt. The results of science are never
"assured"; they are tentative and subject to constant revision. It is
even possible, as in this case of light, that the theories discarded a century ago,
may return to favor in a somewhat altered form. And most pertinently for the present
discussion on evolution it must be insisted that the acceptance of a theory whose
factors are unknown, not to say unknowable, is extremely bad science.
At this point the evolutionists will undoubtedly reply that the
propagation of light is a fact whether or not we know its factors. To this I wish
to make a shorter and a longer reply.
First, the propagation of light is ordinarily regarded as a fact
because and only because of very careful attention to the factors. For centuries
light was considered to be a non-propagated force, like gravitation, because no
one was able to detect and measure its speed. It was indeed in Newton's own lifetime
that Roemer (1676) observed the differences in time between the near and far eclipses
of Jupiter's satellites and concluded that light has a finite velocity. Once again
the acceptance of the theory came with a careful attention to the detailed factors.
VI. Confusion of Terms.
The second and longer reply to the assertion that evolution is
a fact draws attention to the ambiguity of the term evolution. Evolution has two
or more distinctly different meanings. The statement that evolution is a fact depends
on this ambiguity. Dobzhansky [Genetics and the Origin of Species, p.--, 1951) defines
evolution in four clauses, the first two of which are pertinent to this argument.
"The theory of evolution asserts that (1) the beings now living have descended
from different beings which lived in the past." This says nothing more than
that we all had parents. If this is all that evolution means, and Howells also defines
it merely as "descent with modification," that is, if the word simply
means that nature exhibits changes, or that different breeds of dogs and foxes have
come into being, then for all colloquial purposes we can very well admit that evolution
is a fact. But such a view of evolution was not what Christians were protesting
against when they attacked evolution; nor was it the view that the evolutionists
were propagating when they provoked the protest.
But if, on the other hand, the term evolution designates an atheistic,
non-supernatural, spontaneous development of simple life from inanimate matter and
the rise of all present forms of life through a slow and gradual development
from that simplest form, the declaration that evolution is a fact would lose its
plausibility. Yet this is the view that is propagated. Dobzhansky does not put it
into his definition, but in other places he asserts, as we have seen, that life
actually sprang from inorganic matter. He rejects vitalism, rules out all teleology,
and accepts the mechanistic hypothesis. He says explicitly that "the diversity
[among organisms] has not arisen from a whim or caprice [or as we should say, from
the sovereign choice and purpose] of some deity" (Evolution, Genetics, and
Man, p. 20-21; Genetics and the Origin of Species, p.cq. This is evolution; but
who could with intellectual honesty claim that this athistic view is a fact better
substantiated than the tentative theories of light?*
If a fair survey of the field of battle is to be made, the evolutionist
must not be allowed to use one theory, a detailed mechanistic and atheistic theory,
for his attack, and a different theory, a vague and general theory, for his defense.
To ridicule Christians for denying observed change when in fact they are denying
atheistic naturalism is a technique of propaganda, not science. Nor is it calm judgment
to accuse Christians of denying actually observed changes when in fact they are
questioning un- observed alleged changes and pointing out the limits of the evidence.
Although Dobzhansky denies divine providence without acknowledging
his denial in the definition of evolution, his other clauses are more definite than
the vague statement of clause one. He adds, " (2) the evolutionary changes
were more or less gradual, so that if we could assemble all the individuals which
have ever inhabited the earth, a fairly continuous array of forms would emerge."
Since this notion of a gradual change and a continuous array
is a part of the definition, this too must be a fact, if evolution is a fact. If
"at present, an informed and reasonable person can hardly doubt the validity
of the evolution theory," and if "the very rare exceptions prove only
that some people have emotional biases" (ibid. p. 11), then doubt as to the
continuity of the array is also subject to these strictures.
What then are we to make of the doubts indicated in the following
quotation from Richard Goldschmidt, The Material Basis of Evolution (pp. 6, 7).
Attention is directed to the list of detailed factors with which the quotation ends.
After stating that he "cannot agree with the viewpoint of the textbooks that
the problem of evolution has been solved" Goldschmidt continues,
"This viewpoint... must take it for granted... that all possible differences
including the most complicated adaptations, have been slowly built up by the accumulation
of such mutations. We shall try to show that this viewpoint does not suffice to
explain the facts ... I may challenge the adherents of the strictly Darwinian view...
to try to explain the evolution of the following features by accumulation and selection
of small mutants: hair in mammals, feathers in birds, segmentation of arthropods
and vertebrates, the transformation of the gill arches in phylogeny including the
aortic arches, muscles, nerves, etc." Then for good measure Goldschmidt continues
with thirteen other factors.
Later (p. 210) he says, "Thus we have been forced to assume
large evolutionary steps... involving the whole system of the organism." He
mentions another scientist "who says that the change from one species to another
must be in one or, at most, a few large steps, changing many or all characters of
the plant at once."
Now, if there is no continuous array of forms, and if the appearance
of a new species occurs in one large step, involving the whole system of the organism,
then, however Goldschmidt himself might prefer it, and I am not implying that he
would put it this way, it would seem that biology is much closer to the view of
special creation than the original evolutionists like Hackel and Huxley would find
comfortable. It was for such reasons as these that I said above that the special
acts of creation listed in Genesis are much fewer than the actual status of biology
seems to require.
In conversation a botanist friend of mine expressed the conclusion
that quite aside from animals it was impossible to believe that all plants had evolved
from a single original form. Before geology had made as much progress as it now
has, it was possible to hope, my friend said, that the gaps would be filled up by
later discoveries; but now the examination of strata has been so extensive that
a discovery of the many necessary intermediate forms seems quite unlikely.
In conclusion, what is the outcome of this century-old battle?
It is true that the defenders of divine creation made a number of unfortunate
blunders; but it is also true that the evolutionary theory has not emerged unscathed.
The evolution that Christianity attacked, the theory that brings life out of matter
without divine intervention, is still a theory without evidence and not a fact with
which science may rest assured.
Perhaps the evolutionists have not retreated under the pressure
of theological attack; but the weight of scientific evidence itself, the detailed
factors, the insoluble problems, and above all the rigor of a sound philosophy of
science have forced admissions that may be said at least to border on special creation.
This is no doubt as much as can be expected from purely scientific methodology.
*An evolutionist who explicitly accepts mechanism cannot with good grace complain of being held to the standards of mechanistic science.
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