The world will not be inherited by the strongest, it will be inherited by those most able to change.

The moral faculties are generally esteemed, and with justice, as of higher value than the intellectual powers. But we should always bear in mind that the activity of the mind in vividly recalling past impressions is one of the fundamental though secondary bases of conscience. This fact affords the strongest argument for educating and stimulating in all possible ways the intellectual faculties of every human being.

... probably all the organic beings which have ever lived on this earth have descended from some one primordial form, into which life was first breathed.

I am dying by inches, from not having any body to talk to about insects.

We cannot fathom the marvelous complexity of an organic being; but on the hypothesis here advanced this complexity is much increased. Each living creature must be looked at as a microcosm--a little universe, formed of a host of self-propagating organisms, inconceivably minute and as numerous as the stars in heaven.

Man in his arrogance thinks himself a great work, worthy the interposition of a great deity. More humble and I believe true to consider him created from animals.

The more we know of the fixed laws of nature the more incredible do miracles become, - that the men at that time were ignorant and credulous to a degree almost incomprehensible by us, - that the Gospels cannot be proved to have been written simultaneously with the events, - that they differ in many important details, far too important as it seemed to me to be admitted as the usual inaccuracies of eye-witnesses; - by such reflections as these... I gradually came to disbelieve in Christianity as a divine revelation.