Life is simply the reification of the process of living.

Scientific progress consists in the development of new concepts.

Mathematics is as little a science as grammar is a language.

Our understanding of the world is achieved more effectively by conceptual improvements than by discovery of new facts...

...anyone who writes about "Darwin's theory of evolution" in the singular, without segregating the theories of gradual evolution, common descent, speciation, and the mechanism of natural selection, will be quite unable to discuss the subject competently.

Evolution as such is no longer a theory for a modern author. It is as much a fact as that the earth revolves around the sun.