The extreme rarity of transitional forms in the fossil record persists as the trade secret of paleontology.

Every day I walk myself into a state of well-being and walk away from every illness; I have walked myself into my best thoughts.

To be a teacher does not mean simply to affirm that such a thing is so, or to deliver a lecture, etc.

You love the accidental. A smile from a pretty girl in an interesting situation, a stolen glance, that is what you are hunting for, that is a motif for your aimless fantasy. You who always pride yourself on being an observateur must, in return, put up with becoming an object of observation. Ah, you are a strange fellow, one moment a child, the next an old man; one moment you are thinking most earnestly about the most important scholarly problems, how you will devote your life to them, and the next you are a lovesick fool. But you are a long way from marriage.

Spiritual superiority only sees the individual. But alas, ordinarily we human beings are sensual and, therefore, as soon as it is a gathering, the impression changes - we see something abstract, the crowd, and we become different. But in the eyes of God, the infinite spirit, all the millions that have lived and now live do not make a crowd, He only sees each individual.

Christendom has done away with Christianity without being quite aware of it.

I have only one confidant, and that is the silence of night.