From the Fact of Evolution to the Philosophy of Evolutionism

FROM THE FACT OF EVOLUTION TO THE PHILOSOPHY OF EVOLUTIONISM PART I: FROM THE FACT OF EVOLVTION STATEMENTS made by serious students of contemporary evolutionary theory seem to be, even to this day, in open conflict about the " fact of evolution." At the Darwin Centennial Celebration held at the University of Chicago (November, 1959), the statement was constantly reiterated : " Biologists one hundred years after Darwin take the fact of evolution for granted, as a necessary basis for interpreting the phenomena of life." 1 Huxley repeated the point: " The evolution of life is no longer a theory; it is a fact and the basis of all our thinking." 2 Dr. Sol Tax, chairman of the Convention, summed up the panel discussions by extending the concept to all areas of scientific endeavor: But perhaps most of our schools still teach evolution, not as a fact, but as only one alternative among explanations of how the world has come to be what it is. No matter what gets done about our religious beliefs, this particular phenomenon must now come to an end. We cannot deal with the difficult problems of the world unless our education takes account of demonstrated empirical fact. (Italics added.) 3 However, in one of the most critical papers submitted at the Centennial, Dr. E. C. Olson suggests an underlying confusion involved in these statements. He writes: It is certain that few negative responses would result from the simple question "Is the general concept of organic evolution valid? " 1 Evolution After Darwin, edited by Sol Tax (Chicago, 1960) III, 107. This three-volume work contains the University of Chicago Centennial papers and discussions and will be used as a constant reference. Hereafter, the worl$: will be signified by the initials EAD. • Ibid., p. 111. • Ibid., p. ~47. 463 464 RAYMOND J. NOGAR were it to be submitted to the biologists working the various disciplines today. If, however, a second question were asked, one requiring a definition of organic evolution, it is equally likely that a varied suite of answers would result, and, if the answers were honest, there would be a fair sprinkling to the effect " I don't know." 4 After insisting that there is a silent segment of significant numbers among biologists and other scientists who feel that much of the fabric of evolutionary theory accepted by the majority today is actually undemonstrated or even false, Olson goes on: The statement is frequently made that organic evolution is no longer to be regarded as a theory, but is a fact. This, it seems to me, reveals a curious situation that causes considerable difficulty in understanding evolution both among laymen and among biologists who are not intimately concerned with its study . . . If organic evolution can be defined simply and loosely as the changes of organisms through successive generations in time, then it can hardly be questioned that, within our understanding of the earth and its life, evolution has occurred. In this sense it must be considered a reality ...5 If, however, the definition of evolution goes further and asserts that contemporary synthetic theory (neo-Darwinian, mutation-selection) is the theory of evolution, as was done many times during the Convention,6 then, Dr. Olson points out, that " fact of evolution " must be rejected as unproved and invalid. The explanation of how the process of orderly change of successive generations through time has been accomplished must be dissociated from the statement that such an orderly succession has taken place. Only then will many scientists accept the proposition " evolution is a fact." 7 Olson's critical series of observations in the midst of the Centennial discussion of the status of evolutionary theory today throws important light upon the confusion which has reigned for over a decade about this proposition: " evolution is a fact." In 1951, the eminent geneticist T. Dobzhansky wrote: ' Op. cit., I, 5W. • Ibid., p. 5!'l6. • Loc. cit. • Ibid., p. 5!'l7. FACT OF EVOLUTION TO THE PHILOSOPHY OF EVOLUTIONISM 465 Evolutionists of the nineteenth century were interested primarily in demonstrating that evolution has actually taken place. They succeeded eminently well. Evolution as an historical process is established as thoroughly and completely as science can establish facts of...