Any work of science, no matter what its point of departure, cannot become fully convincing until it crosses the boundary between the theoretical and the experimental: Experimentation must give way to argument, and argument must have recourse to experimentation.

In living off all the reflecting light furnished by poets, the I which dreams the reverie reveals itself not as poet but as poetizing I.

The human mind has claimed for water one of its highest values-the value of purity.

Even a minor event in the life of a child is an event of that child's world and thus a world event.

He who ceases to learn cannot adequately teach.

Ideas are invented only as correctives to the past. Through repeated rectification of this kind one may hope to disengage an idea that is valid.

Nothing is forgotten in the processes of idealization. Reveries of idealization develop, not by letting oneself be taken in by memories, but by constantly dreaming the values of a being whom one would love. And that is the way a great dreamer dreams his double. His magnified double sustains him.