Our belief in any particular natural law cannot have a safer basis than our unsuccessful critical attempts to refute it.

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

We have become makers of our fate when we have ceased to pose as its prophets.

A theory is just a mathematical model to describe the observations.

While differing widely in the various little bits we know, in our infinite ignorance we are all equal.

No rational argument will have a rational effect on a man who does not want to adopt a rational attitude.

A rationalist is simply someone for whom it is more important to learn than to be proved right; someone who is willing to learn from others - not by simply taking over another's opinions, but by gladly allowing others to criticize his ideas and by gladly criticizing the ideas of others