Metaphysical ghosts cannot be killed, because they cannot be touched; but they may be dispelled by dispelling the twilight in which shadows and solidities are easily confounded. The Vital Principle is an entity of this ghostly kind; and although the daylight has dissipated it, and positive Biology is no longer vexed with its visitations, it nevertheless reappears in another shape in the shadowy region of mystery which surrounds biological and all other questions.

The great desire of this age is for a doctrine which may serve to condense our knowledge, guide our researches, and shape our lives, so that conduct may really be the consequence of belief

Remember that every drop of rain that falls bears into the bosom of the earth a quality of beautiful fertility.

It is unhappily true that much insincere Literature and Art, executed solely with a view to effect, does succeed by deceiving the public.

Science is the systematic classification of experience.

Speak for yourself and from yourself, or be silent.

In Science the paramount appeal is to the Intellect-its purpose being instruction; in Art, the paramount appeal is to the Emotions-its purpose being pleasure.