To enter into your own mind you need to be armed to the teeth.

Cognition reigns but does not rule.

His heart is a desert island.... The whole scope, the whole energy of his mind surround and protect him; his depths isolate him and guard him against the truth. He flatters himself that he is entirely alone there.... Patience, dear lady. Perhaps, one day, he will discover some footprint on the sand.... What holy and happy terror, what salutary fright, once he recognizes in that pure sign of grace that his island is mysteriously inhabited!

The world acquires value only through its extremes and endures only through moderation; extremists make the world great, the moderates give it stability.

One had to be a Newton to notice that the moon is falling, when everyone sees that it doesn't fall.

The mind has transformed the world, and the world is repaying it with interest. It has led man where he had no idea how to go.

The folly of mistaking a paradox for a discovery, a metaphor for a proof, a torrent of verbiage for a spring of capital truths, and oneself for an oracle, is inborn in us.