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

There is much else in the literary idiom of nature-philosophy: nothing-buttery, for example, always part of the minor symptomatology of the bogus.

Scientists who think science consists of unprejudiced data-gathering without speculation are merely cows grazing on the pasture of knowledge.

Heredity proposes and development disposes.

It is ... a sign of the times-though our brothers of physics and chemistry may smile to hear me say so-that biology is now a science in which theories can be devised: theories which lead to predictions and predictions which sometimes turn out to be correct. These facts confirm me in a belief I hold most passionately-that biology is the heir of all the sciences.

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.