A hallucination is a fact, not an error; what is erroneous is a judgment based upon it.

In human relations one should penetrate to the core of loneliness in each person and speak to that.

What science cannot discover, mankind cannot know.

I do not pretend to start with precise questions. I do not think you can start with anything precise. You have to achieve such precision as you can, as you go along.

Our beliefs are, however, often contrary to fact.

The observer, when he seems to himself to be observing a stone, is really, if physics is to be believed, observing the effects of the stone upon himself.

Writing can be either readable or precise, but not at the same time.