Natural Selection and Teleology
In a nutshell, the idea of natural selection goes like this:
(a) Assume a population of organisms;
(b) Further assume that in each generation there is a certain amount of spontaneous, random variability among the traits of the organisms, that some of these traits will be more conducive to the survival and hence reproduction of their bearers than others, and that these favorable traits are heritable;
(c) Then, on average, the organisms with the traits that are more conducive to survival and reproduction will survive and reproduce at a higher rate than other organisms lacking those favorable traits;
(d) Hence, organisms with survival- and reproduction-promoting traits will tend to increase as a proportion of the population over time.
Given premises (a) and (b), conclusions (c) are (d) are clearly unexceptionable. But the question is not whether natural selection, as an abstract explanatory pattern, is logical valid. The question is whether, as a scientific theory, natural selection is adequate to account for the phenomena. More particularly, the question is whether invoking natural selection allows us to reduce teleology to mechanism without remainder.
It is obvious for several reasons that natural selection cannot claim to have eliminated all reference to teleology in biology. In the first place, the selection schema depends essentially on the concept of survival, which is itself a teleological concept. Only organisms survive; nonliving aggregates of matter just go on existing for shorter or longer periods of time. Existence is a matter of complete indifference to inorganic matter. Only living things have a preference---a prejudice, if you will---in favor of existence. This is what we mean by "survival," and it is the very heart both of teleology and of the theory of natural selection. Hence, natural selection is teleological to the core.
For another thing, it is the differential success of traits that gives rise to the differential reproduction of organisms. Success is a quintessentially teleological notion. Thus, it is teleology---the fact that some biological functions are better than others---that explains natural selection, not the other way around. This means that, so far as their claim to have eliminated teleology is concerned, Darwinists have gotten the order of explanation backwards.
Finally, a key element of the claim of natural selection to have reduced teleology to mechanism is the notion that the variation of traits is random, which, in this context, must mean functionally uncoordinated. But this assumption will not withstand scrutiny. If every "trait" (in effect, every macromolecule) in every organism that ever existed had to vary in a truly random way, it does not take much mathematical sophistication to see that evolution would be impossible. Fred Hoyle's famous image of a Boeing 747 assembled by a tornado sweeping through a junkyard does not begin to suggest the order of magnitude of the probabilities involved if all the individual elements of even a single living cell had to vary independently of one another. And yet that is precisely the assumption that is required in order to sustain the claim that natural selection reduces teleology to mechanism. But as soon as we allow the elements of the cell to vary, not independently, but in a coordinated fashion, then we have slipped teleology in again by the back door. It is the tacit assumption of the functional coordination of variations that gives the theory of natural selection whatever superficial plausibility it may have.
If neither molecular biology nor natural selection can eliminate teleology individually, could they perhaps do so jointly? The answer to this question is no. Rather, what happens is that, when either of these disciplines is subjected to searching scrutiny, its practitioners are obliged to admit that they cannot really carry out the putative reduction on their own. But they do not feel this admission to be fatal, because they can always refer the inquirer to the other discipline! In other words, insofar as their philosophical pretensions are concerned, molecular biology and natural selection together function like the shells in a confidence game---whichever theory the customer points to, he always learns that the final reduction of teleology to mechanism is underneath the other one.
* Molecular Biology and Teleology
Editor(s): James Barham