It belongs to the self-respect of intellect to pursue every tangle of thought to its final unravelment.

Learning is often spoken of as if we are watching the open pages of all the books which we have ever read, and then, when occasion arises, we select the right page to read aloud to the universe.

Civilizations can only be understood by those who are civilized.

Problems are only opportunities in disquise.

Education with inert ideas is not only useless; it is above all things harmful.

Do not teach too many subjects and what you teach, teach thoroughly.

It is natural to think that an abstract science cannot be of much importance in affairs of human life, because it has omitted from its consideration everything of real interest.