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!

Science is feasible when the variables are few and can be enumerated; when their combinations are distinct and clear. We are tending toward the condition of science and aspiring to do it. The artist works out his own formulas; the interest of science lies in the art of making science.

The trouble with our times is that the future is not what it used to be.

Thanks to photography, the eye grew accustomed to anticipate what it should see and to see it; and it learned not to see nonexistent things which, hitherto, it had seen so clearly.

History is the most dangerous product which the chemistry of the mind has concocted. Its properties are well known. It produces dreams and drunkenness. It fills people with false memories, exaggerates their reactions, exacerbates old grievances, torments them in their repose, and encourages either a delirium of grandeur or a delusion of persecution. It makes whole nations bitter, arrogant, insufferable and vainglorious.

Whatever we succeed in doing is a transformation of something we have failed to do. Thus, when we fail, it is only because we have given up.

The universe is built on a plan the profound symmetry of which is somehow present in the inner structure of our intellect.