The Character of
Evolutionary Theory
G.G. Simpson, The Meaning of Evolution (Bantam
Books, New York, 1967), p. 246.
In reality, gathering of facts, without a formulated reason for doing so
and a pretty good idea as to what the facts may mean, is a sterile occupation and has not
been the method of any important scientific advance. Indeed facts are elusive and you
usually have to know what you are looking for before you can find one.
Editor's comment: So what is wrong with scientists who are Christians
and believers in divine creation being critical of evolutionary interpretations and
pursuing their studies of biological questions within the conceptual framework of special
creation?
G.G. Simpson, Tempo and Mode in Evolution
(Columbia University Press, New York, 1944), p. 76n.
...But scientific history conclusively demonstrates that the progress of
knowledge rigidly requires that no non-physical postulate ever be admitted in connection
with the study of physical phenomena. We do not know what is and what is not explicable in
physical terms, and the researcher who is seeking explanations must seek physical
explanations only...
Editor's comment: It is certainly
true that empirical science cannot discover immaterial causes and explanations. Simpson's
assertion, on the other hand, constitutes the insertion into the definition of science of
the assumption of a closed materialistic universe. He would mandate thought control for
all scientists on pain of dissenters' loss of their professional careers. This is
intolerance, bigotry and the denial of academic freedom carried to the extreme limit. It
is intolerable, especially so in the guise of science.
T.H. Huxley, Darwiniana (D. Appleton and Co.,
New York, 1901), pp. 468-469.
But you must recollect that when I say I think it is either Mr. Darwin's
hypothesis or nothing, that either we must take his view, or look upon the whole of
organic nature as an enigma, the meaning of which is wholly hidden from us: you must
understand that I mean that I accept it provisionally, in exactly the same way as I accept
any other hypothesis. Men of science do not pledge themselves to creeds; they are bound by
articles of no sort; there is not a single belief that it is not a bounden duty with them
to hold with a light hand and to part with cheerfully, the moment it is really proved to
be contrary to any fact, great or small.
C. Leon Harris, Perspectives in Biology and Medicine,
Winter 1975, pp. 183-184.
I have suggested that the neo-Darwinian theory of evolution rests on the
axioms that all heritable variations in fitness result from chance mutations and that
there is natural selection for fitness. There are several consequences for evolution and
for biology in general.
First, the axiomatic nature of the neo-Darwinian theory places the
debate between evolutionists and creationists in a new perspective. Evolutionists have
often challenged creationists to provide experimental proof that species have been
fashioned de novo. Creationists have often demanded that evolutionists show how chance
mutations can lead to adaptability, or to explain why natural selection has favored some
species but not others with special adaptations, or why natural selection allows
apparently detrimental organs to persist. We may now recognize that neither challenge is
fair. If the neo-Darwinian theory is axiomatic, it is not valid for creationists to demand
proof of the axioms, and it is not valid for evolutionists to dismiss special creation as
unproved so long as it is stated as an axiom. ...
Another possibility is that alternatives to the neo-Darwinian
axioms can be proposed and their consequences tested. This will undoubtedly
require great
independence of thought. Bertalanffy, Waddington, Olson, and King and Jukes
have questioned the axiom of natural selection for several reasons,
but the axioms seem so
convincing that alternatives are difficult to conceive. The axiom of natural
selection is so ingrained that a phrase like "the action of natural selection is very strong" seems
perfectly acceptable even though it often means simply that a lot of
organisms died. Many alternatives to the neo-Darwinian axioms would
be criticized not because they violate
accepted facts but because they violate deeply rooted concepts. It is much
more likely that new and productive axioms will be proposed if the
present neo-Darwinian theory is
itself recognized as axiomatic.
W. Thorpe, "Reductionism v. Organicism," New
Scientist, vol. 43, 25 Sept. 1969, p. 636, reviewing Beyond Reductionism,
Arthur Koestler and J.R. Smythies, editors (Hutchinson University Press, New York, 1969)
...Further, von Bertalanffy in discussing natural selection, points out
that the selectionist's argument is one that can be expanded or elaborated to cover
anything that may conceivably have happened during the evolution of animals and plants. If
selection is taken as an axiomatic and a priori principle, it is always possible
to imagine auxiliary hypotheses--unproved, and by nature unprovable--to make it work in
any special case. He argues that this procedure corresponds exactly to that of epicycles
in the Ptolemaic systems: if planetary motion is a priori cyclic, then any orbit,
however seemingly regular, can be explained by introducing more epicycles. Similarly, some
adaptive value (and consequent selective advantage, survival due to differential
reproduction, etc.) can always be constructed or imagined. It seems to follow from this
that no amount of theoretical argument as to how the evolutionary results which we now see
may have been brought about, can carry complete conviction.
Ernst Mayr, et al., Methods and Principles of
Systematic Zoology (McGraw-Hill, New York, 1953), p. 42.
...Every one of the sources of information on phylogeny that has been
used in the past has its limitations and pitfalls. This is true for genetics, physiology
(including serology), embryology, and zoogeography. It is even true for paleontology,
because there are several interpretations possible for many fossil remains, particularly
if they are incomplete.
Alan Boyden, Physiological Zoology, vol. 15,
April 1942, p. 117.
...Actually we shall never be able to prove the common ancestry of all
animals, and therefore we have no right to state as a fundamental principle what must
always remain an assumption.
H.W. Smith, From Fish to Philosopher (Little,
Brown and Co., Boston, 1953), p. 26.
...As our present information stands...the best place to start the
evolution of the vertebrates is in the imagination.
Charles Darwin, The Origin of Species (J.M.
Dent and Sons Ltd., London, 1971), p. 18.
...For I am well aware that scarcely a single point is discussed in this
volume on which facts cannot be adduced, often apparently leading to conclusions directly
opposite to those at which I have arrived. A fair result can be obtained only by fully
stating and balancing the facts and arguments on both sides of each question; and this is
here impossible.
Ernst Mayr, Systematics and the Origin of Species
(Columbia University Press, New York, 1942), p. 28.
...Systematics is in a more difficult position than other sciences...we
have an almost unlimited diversity of opinion in answer to such questions as: What is a
species? How do species originate? Are systematic categories natural? And so forth. There
is no uniform point of view among taxonomists; in fact, in regard to many of these
questions there may not even be a majority opinion.
Charles Darwin, letter to Herbert Spencer, 23 Feb. 1860,
in Life and Letters of Herbert Spencer, Vol. I, David Duncan, editor (D. Appleton
and Co., New York, 1908), p. 128.
...Of my numerous (private) critics, you are almost the only one who has
put the philosophy of the argument, as it seems to me, in a fair way--namely, as an
hypothesis (with some innate probability, as it seems to me) which explains several groups
of facts.
Charles Darwin, letter to G. Bentham, 22 May 1863, in The
Life and Letters of Charles Darwin, Vol. II, Francis Darwin, editor (D. Appleton and
Co., New York, 1898), p. 210.
...In fact, the belief in Natural Selection must at present be grounded
entirely on general considerations. (1) On its being a vera causa, from the struggle for
existence; and the certain geological fact that species do somehow change. (2) From the
analogy of change under domestication by man's selection. (3) And chiefly from this view
connecting under an intelligible point of view a host of facts. When we descend to details
we can prove that no one species has changed [i.e., we cannot prove that a single species
has changed]: nor can we prove that the supposed changes are beneficial, which is the
groundwork of the theory. Nor can we explain why some species have changed and others have
not. The latter case seems to me hardly more difficult to understand precisely and in
detail than the former case of supposed change.
Ledyard Stebbins, "Adaptive Shifts and Evolutionary
Novelty," in Studies in the Philosophy of Biology, F.J. Ayala and Theodosius
Dobzhansky, editors (University of California Press, Berkeley, 1974), pp. 286-287.
...the scientist whose major interest is the entire course of
evolution...by extrapolation...must reach out into remote areas of scientific knowledge.
He can extrapolate successfully only by acquiring a broad knowledge of apparently
disparate facts. On the basis of a carefully considered and clearly expressed philosophy
he must put these facts together, like the pieces of a jigsaw puzzle, into a rational,
harmonious, synthetic whole. ...
Editor's comment: So why cannot
scientists who are Christians who believe in creation form hypotheses and explanations
constructed under the conceptual framework of their philosophy?
...On the other hand, the macroevolutionary focus inevitably provides
generalizations which, whether true or false, have wide public appeal. The public,
however, both scientists and nonscientists, does not have enough background to
discriminate between broadly based, well integrated hypotheses and wild speculations that
extrapolate from a few facts that the theorist happens to regard as important. In the
field of evolutionary theory, acceptance by the intellectual public of a point of view
often appears to depend more upon the way in which it is packaged in catchy phrases and
titillating examples than upon the solid worth of the package's contents.
G.A. Kerkut, Implications of Evolution
(Pergamon Press, New York, 1960), pp. 6-7.
...Before one can decide that the theory of Evolution is the best
explanation of the present-day range of forms of living material one should examine all
the implications that such a theory may hold. Too often the theory is applied to, say, the
development of the horse and then because it is held to be applicable there it is extended
to the rest of the animal kingdom with little or no further evidence.
There are, however, seven basic assumptions that are often not mentioned
during discussions of Evolution. ...
...I shall consider that...these assumptions form the "General
Theory of Evolution."
The first point that I should like to make is that these seven
assumptions by their nature are not capable of experimental verification. ...
Ibid., p. 150.
What conclusions, then, can one come to concerning the validity of the
various implications of the theory of evolution? If we go back to our initial assumptions
it will be seen that the evidence is still lacking for most of them.
(1) The first assumption was that non-living things gave rise to living
material. This is still just an assumption.
[Editor's note: It remains an assumption 29 years later].
Ibid., p. 154.
In effect, much of the evolution of the major groups of animals has to
be taken on trust. There is a certain amount of circumstantial evidence but much of it can
be argued either way. ...
Ibid., p. 155.
Perhaps it is appropriate here to quote a remark made by D'Arcy Thompson
in his book On Growth and Form. "If a tiny foraminiferan
shell, a Lagena for instance, be found living today, and a shell indistinguishable
from it to the eye be found
fossil in the calk or some still more remote geological formation, the
assumption is deemed legitimate that the species has `survived' and has
handed down its minute specific
character or characters from generation to generation unchanged for untold
millions of years. If the ancient forms be like rather than identical with
the recent, we still assume
an unbroken descent, accompanied by hereditary transmission of common characters
and progressive variations. And if two identical forms be discovered at
the ends of the earth,
still (with slight reservation on the score of possible `homoplasy') we
build a hypothesis on this fact of identity, taking it for granted that
the two appertain to a common stock,
whose dispersal in space must somehow be accounted for, its route traced,
its epoch determined and its causes discussed or discovered. In short,
the Naturalist admits no
exception to the rule that a natural classification can only be a genealogical
one, nor ever doubts that `the fact that we are able to classify organisms
at all in accordance
with the structural characteristics which they present is due to their
being related by descent.'
What alternative system can we use if we are not to assume that all
animals can be arranged in a genealogical manner? The alternative is to indicate that
there are many gaps and failures in our present system and that we must realize their
existence. It may be distressing for some readers to discover that so much in zoology is
open to doubt, but this in effect indicates the vast amount of work that remains to be
done. ...
Ibid., p. 157.
There is a theory which states that many living animals
can be observed over the course of time to undergo changes so the new
species are formed. This can be
called the "Special Theory of Evolution" and can be demonstrated in certain
cases by experiments. On the other hand there is the theory that all the living forms in
the world have arisen from a single source which itself came from an inorganic form. This
theory can be called the "General Theory of Evolution" and the
evidence that supports it is not sufficiently strong to allow us to consider
it as anything more than a
working hypothesis. It is not clear whether the changes that bring about
speciation are of the same nature as those that brought about the development
of new phyla. The answer will
be found by future experimental work and not by dogmatic assertions that
the General Theory of Evolution must be correct because there is nothing
else that will satisfactorily
take its place.
F.A. Hooten, Apes, Men and Morons (Putnam, New
York, 1938), p. 107.
...that a dispassionate interpretation of new fossil evidence is usually
obtainable only when one awaits the rewriting of the material by persons not emotionally
identified with the specimen.
Verne Grant, The Origin of Adaptations
(Columbia University Press, New York, 1963), p. 107.
...It is true that the evolutionary changes which have been directly
observed are very minor compared with some of the transformations required by the
evolution hypothesis.
...The evolution of a black moth from a grey moth, or of a corn plant
with highly proteinaceous kernels from one with slightly proteinaceous kernels, during a
period of years leaves the final product unchanged as far as its basic characteristics are
concerned. The evolution hypothesis embraces, in addition to small evolutionary changes
from one kind of moth or corn plant into another, also such far-reaching transformations
as are involved in the differentiation of the carnivores, ungulates, primates, and bats
from some common mammalian ancestor.
Ibid., p. 388.
...Experimental evolution deals of necessity with only the simplest
levels of the evolutionary process, sometimes called microevolution.
L. Harrison Matthews in Introduction to The Origin
of Species (J.M. Dent & Sons Ltd., London; Everyman's University
Library; 1972), pp. x-xi.
Most biologists now accept `the fact of evolution', because the theory
of evolution conveniently explains the known facts. Some biologists, however, are unable
to support it; for example Professor W.R. Thompson, the author of the Introduction for the
last edition of the Origin in the Everyman's Library. Professor Thompson examines
the book critically from the point of view of a Christian fundamentalist, and holds that
it is a common-sense conviction that plants, animals and men can be distinguished because
they are radically different. He deplores the anti-religious thought induced by acceptance
of the theory of evolution and, while admitting that the Origin gave a great
stimulus to biological research, he thinks that its effect has been bad for biology and
for humanity.
Much of Professor Thompson's criticism of Darwin's text is unanswerable.
In accepting evolution as a fact, how many biologists pause to reflect that science is
built upon theories that have been proved by experiment to be correct, or remember that
the theory of animal evolution has never been thus proved? Even `Darwin's bulldog', as
Thomas Huxley once called himself, wrote in 1863: `I adopt Mr Darwin's hypothesis,
therefore, subject to the production of proof that physiological species may be produced
by selective breeding'--meaning species that are infertile if crossed. That proof has
never been produced, though a few not entirely convincing examples are claimed to have
been found. The fact of evolution is the backbone of biology, and biology is thus in the
peculiar position of being a science founded on an unproved theory--is it then a science
or a faith? Belief in the theory of evolution is thus exactly parallel to belief in
special creation--both are concepts which believers know to be true but neither, up to the
present, has been capable of proof.
Editor's correction: Matthews is
in error at one point. Thompson did not consider himself a Christian fundamentalist, nor
did he write his Introduction from that point of view.
W.R. Thompson, Science and Common Sense (Longmans,
Green & Co., London, 1937), pp. 228-229.
The object of natural science is the explanation of the things and
events observed in the world, in terms of natural causes. The hypothesis that the
diversity of living things is due to natural forces and interactions is thus, for natural
science, a perfectly legitimate hypothesis. These reasons, which are methodological, are
not, however, reasons for believing in natural Evolution or for accepting it as a
truth. The approximation of a hypothesis to the status of a truth
depends essentially on its assimilative capacity; in other words, on the
extent to which it allows
us to assemble the known facts in a coherent rational structure or predict
effects from causes. Unfortunately, none of the evolutionary hypotheses
now available permits a
satisfactory integration of the facts. Many facts fit well enough into
the broad general theory of Evolution by descent, if its mode and causes
are left unspecified. Other facts
can be brought into agreement with it only on the assumption that our information
is incomplete, which is doubtless true, but not a satisfactory argument
in favour of the
hypothesis. Furthermore, any scientific theory of natural Evolution should
explain the process as due to specified natural causes, having an effect
that can be experimentally
verified. The absence of an explanation of this kind is an extremely serious
defect and until it has been remedied we certainly cannot assert on scientific
grounds that Evolution
is a fact. Philosophical arguments can be brought forward in support of
the thesis of Natural Evolution, and some of these are by no means negligible.
But as has been shown in
previous chapters, the development of Science, as an autonomous discipline,
seems to entail the rigorous elimination of philosophical notions. When
we compare scientific
statements or proofs of the type we find in works on experimental physiology
or behaviouristic "psychology" with those commonly met with in
evolutionary literature, we see clearly how full evolutionary speculation
is of philosophical
principles and presuppositions. The concept of Evolution is very highly
prized by biologists, for many of whom it is an object of genuinely religious
devotion, because they
regard it as a supreme integrative principle. This is probably the reason
why the severe methodological criticism employed in other departments of
biology has not yet been brought
to bear against evolutionary speculation. There are, however, indications
that this criticism will not now be long delayed. ...
Editor's comment: Over a half
century later the secular scientific and philosophical establishment, unfortunately, has
yet to fulfill Dr. Thompson's prediction.
Richard C. Lewontin, The Genetic Basis of
Evolutionary Change (Columbia University Press, New York, 1974), 28-29.
I have presented the balance and classical hypotheses of genetic
variation as a priori predictions about what would be observed
if a method could actually be found to describe the distribution of genotypes
in a population, rather than
first reviewing the evidence and then presenting these hypotheses as alternative
interpretations of ambiguous observations. It is a common myth of science
that scientists collect evidence about some issue and then by logic and "intuition" form what
seems to them the most reasonable interpretation of the facts. As more facts accumulate,
the logical and "intuitive" value of different interpretations
changes and finally a consensus is reached about the truth of the matter.
But this textbook myth has
no congruence with reality. Long before there is any direct evidence, scientific
workers have brought to the issue deep-seated prejudices; the more important
the issue and the
more ambiguous the evidence, the more important are the prejudices, and
the greater the likelihood that that two diametrically opposed and irreconcilable
schools will appear.
Even when seemingly incontrovertible evidence appears to decide the matter
the conflict is not necessarily resolved, for a slight redefinition of
the issue results in a continuation
of the struggle. It is part of the dialectic of science that the apparent
solution of a problem usually reveals that we have not asked the right
question in the first place, or
that a much more difficult and intractable problem lies just below the
surface that has been so triumphantly cleared away. And in the process
of redefinition of the issues, the
old parties remain, sometimes under new rubrics, but always with old points
of view. This must be the case because schools of thought about unresolved
problems do not derive from
idiosyncratic institutions but from deep ideological biases reflecting
social and intellectual world views. A priori assumptions about the truth of particular
unresolved questions are simply special cases of general prejudices.
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