It is part of my thesis that all our knowledge grows only through the correcting of our mistakes.

Understanding a theory has, indeed, much in common with understanding a human personality. We may know or understand a man's system of dispositions pretty well; that is to say, we may be able to predict how he would act in a number of different situations. But since there are infinitely many possible situations, of infinite variety, a full understanding of a man's dispositions does not seem to be possible.

It is impossible to speak in such a way that you cannot be misunderstood.

Good tests kill flawed theories; we remain alive to guess again.

Every genuine test of a theory is an attempt to falsify it, or to refute it.

I remained a socialist for several years, even after my rejection of Marxism; and if there could be such a thing as socialism combined with individual liberty, I would be a socialist still. For nothing could be better than living a modest, simple, and free life in an egalitarian society.

Whenever we propose a solution to a problem, we ought to try as hard as we can to overthrow our solution, rather than defend it.