I cannot escape the objection that there is no state of mind, however simple, that does not change every moment.

Life does not proceed by the association and addition of elements, but by dissociation and division.

To exist is to change, to change is to mature, to mature is to go on creating oneself endlessly.

We regard intelligence as man's main characteristic and we know that there is no superiority which intelligence cannot confer on us, no inferiority for which it cannot compensate.

The major task of the twentieth century will be to explore the unconscious, to investigate the subsoil of the mind.

When we make the cerebral state the beginning of an action, and in no sense the condition of a perception, we place the perceived images of things outside the image of our body, and thus replace perception within the things themselves.