Great people plant trees they'll never sit under.

In order to acquire learning, we must first shake ourselves free of it.

One main factor in the upward trend of animal life has been the power of wandering.

The way in which the persecution of Galileo has been remembered is a tribute to the quiet commencement of the most intimate change in outlook which the human race had yet encountered. Since a babe was born in a manger, it may be doubted whether so great a thing has happened with so little stir

Human life is driven forward by its dim apprehension of notions too general for its existing language.

Ideas won't keep. Something must be done about them.

Nature gets credit which should in truth be reserved for ourselves: the rose for its scent, the nightingale for its song; and the sun for its radiance. The poets are entirely mistaken. They should address their lyrics to themselves and should turn them into odes of self congratulation on the excellence of the human mind.