Monday, December 30, 2013
The Gravity of Evolutionary Theories
It’s time to tackle here, if only briefly, an issue that tends to make my blood boil: that people do not ‘believe’ in evolution. For what these people laughingly call ‘reasons’ they choose not to accept the overwhelming evidence demonstrating the fact of evolution. It is probably one of the most well-documented phenomena in the whole of science. I’m not going to waste my time arguing the details here, which would not convince these people in any case. No amount of evidence could ever do that. What I am going to take issue with, however, is the argument, made by these people, that evolution is only a theory, and that, therefore, other theories (usually creationism) are of equal standing and should therefore be taught alongside (if not instead of) evolution. This is a complete misunderstanding of what is meant by those who speak about the (or a) theory of evolution.
Let’s get this cleared up once and for all. Evolution is not a theory. Evolution is a well-established and undeniable phenomenon about which certain theories—the best known being Darwin’s theory of evolution by means of natural selection—have been proposed, tested and further developed. Darwin and biologists today are not proposing the theory that life forms on this planet have undergone a long process of evolution. This is the given fact. What they are doing is proposing natural mechanisms by which this process occurs. The theory of evolution by natural selection—the survival of the fittest—is one such (well-supported) theory; but other mechanisms are also considered.
When biologists talk about ‘the theory of evolution’ they are doing so in the same way that physicists talk about ‘the theory of gravity’. Gravity is a given, well-known phenomenon, about which we have certain theories. I don’t suppose that many biblical fundamentalists doubt the reality of gravity as a phenomenon. But then again, one can never be sure…