The human mind treats a new idea the same way the body treats a strange protein; it rejects it.

If a scientist were to cut his ear off, no one would take it as evidence of a heightened sensibility.

To abdicate from the rule of reason and substitute for it an authentication of belief by the intentness and degree of conviction with which we hold it can be perilous and destructive. Religious beliefs give a spurious spiritual dimension to tribal enmities.

The fact that scientists do not consciously practice a formal methodology is very poor evidence that no such methodology exists. It could be said-has been said-that there is a distinctive methodology of science which scientists practice unwittingly, like the chap in Moliere who found that all his life, unknowingly, he had been speaking prose.

The alternative to thinking in evolutionary terms is not to think at all.

I shall borrow two words used for a slightly different purpose by the great demographer Alfred Lotka to distinguish between the two systems of heredity enjoyed by man: endosomatic or internal heredity for the ordinary or genetical heredity we have in common with animals; and exosomatic or external heredity for the non-genetic heredity that is peculiarly our own - the heredity that is mediated through tradition, by which I mean the transfer of information through non-genetic channels from one generation to the next.

It is naïve to suppose that the acceptance of evolution theory depends upon the evidence of a number of so-called "proofs"; it depends rather upon the fact that the evolutionary theory permeates and supports every branch of biological science, much as the notion of the roundness of the earth underlies all geodesy and all cosmological theories on which the shape of the earth has a bearing. Thus antievolutionism is of the same stature as flat-earthism.