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Section 3: Quotations from Scientists

Science, Religion, Creation and Evolution

Does the Theory Lead to Testable Predictions?

Edward S. Deevey, Jr., "The Reply: Letter from Birnam Wood," Yale Review, Vol. 61, 1967, p. 639.

...Unfortunately, for the same reason that happenings do not make good theatre, existential experiments, the sort that might help to demonstrate post-Darwinian evolution, are very hard to design. In fact, by canons promulgated in every textbook, they would be bad experiments. The best ones--I do not say the only good ones, or the only conceivable ones--are still those that nature set up so long ago. Which is why evolutionists are still historians, not prophets.

Ernst Mayr, Science, Vol. 134, 10 Nov. 1961, p. 1503.

I doubt that there is a scientist who would question the ultimate causality of all biological phenomena--that is, that a causal explanation can be given for past biological events. Yet such an explanation will often have to be so unspecific and so purely formal that its explanatory value can certainly be challenged. In dealing with a complex system, an explanation can hardly be considered very illuminating that states: "Phenomenon A is caused by a complex set of interacting factors, one of which is B." Yet often this is about all one can say.

Ibid., p. 1504.

The theory of natural selection can describe and explain phenomena with considerable precision, but it cannot make reliable predictions, except through such trivial and meaningless circular statements as, for instance: "the fitter individual will on the average leave more offspring." Scriven has emphasized quite correctly that one of the most important contributions to philosophy made by the evolutionary theory is that it has demonstrated the independence of explanation and prediction.

Stephen Tolumin, Foresight and Understanding (Harper Torchbooks, New York, 1961), p. 24.

...[Historical theories] have led to no categorical verifiable forecasts whatever. One obvious example is Darwin's theory, explaining the origin of species by reference to variation and natural selection. No scientist has ever used this theory to foretell the coming-into-existence of creatures of a novel species, still less verified his forecast.

R.H. Peters, "Tautology in Evolution and Ecology," American Naturalist, Vol. 110, Jan.-Feb. 1976, p. 1.

I argue that the `the theory of evolution' does not make predictions, so far as ecology is concerned, but is instead a logical formula which can be used only to classify empiricism's and to show the relationships which such a classification implies. Similar criticisms are then made of several ecological concepts. The essence of the argument is that these `theories' are actually tautologies and, as such, cannot make empirically testable predictions. They are not scientific theories at all.

Ibid., p. 11.

Analysis of a number of popular ecological tenets, including natural selection, competitive exclusion, and parts of succession, species diversity, and spatial heterogeneity, reveals that they lack the predictive and operational qualities which define scientific theories. Instead they consist of the logical elaboration of certain axioms. Consequently, they must be termed tautologies.

Tautologies may be useful logical aids, but they cannot replace true theories. Unless ecologists are careful to distinguish the two, their confusion may produce a body of thought resting on metaphysical rather than empirical, predictive science.

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