I care not what subject is taught, if only it be taught well.

Whatever evil voices may rage, Science, secure among the powers that are eternal, will do her work and be blessed.

The secret of genius is to carry the spirit of childhood into maturity.

I'd rather have an ape for an ancestor than a bishop.

If the hypothesis of evolution is true, living matter must have arisen from non-living matter; for by the hypothesis the condition of the globe was at one time such, that living matter could not have existed in it, life being entirely incompatible with the gaseous state.

It seems safe to look forward to the time when the conception of attractive and repulsive forces, having served its purpose as a useful piece of scientific scaffolding, will be replaced by the deduction of the phenomena known as attraction and repulsion, from the general laws of motion.

The improver of natural knowledge absolutely refuses to acknowledge authority, as such. For him, skepticism is the highest of duties; blind faith the one unpardonable sin.