The indestructible is one: it is each individual human being and, at the same time, it is common to all, hence the incomparably indivisible union that exists between human beings.

Self-control means wanting to be effective at some random point in the infinite radiations of my spiritual existence.

Every new discovery is assumed at once into the sum total of knowledge, and with that ceases in a sense to be a discovery; it dissolves into the whole and disappears, and one must have a trained scientific eye even to recognize it after that.

Believing in progress does not mean believing that any progress has yet been made.

The relationship to one's fellow man is the relationship of prayer, the relationship to oneself is the relationship of striving; it is from prayer that one draws the strength for one's striving.

The thornbush is the old obstacle in the road. It must catch fire if you want to go further.

Books are a narcotic.