The quest for precision is analogous to the quest for certainty and both - precision and certainty are impossible to attain.

The survival value of intelligence is that it allows us to extinct a bad idea, before the idea extincts us.

The more we learn about the world, and the deeper our learning, the more conscious, specific, and articulate will be our knowledge of what we do not know, our knowledge of our ignorance

We never know what we are talking about.

The difference between the amoeba and Einstein is that, although both make use of the method of trial and error elimination, the amoeba dislikes erring while Einstein is intrigued by it.

Unlimited tolerance must lead to the disappearance of tolerance. If we extend unlimited tolerance even to those who are intolerant, if we are not prepared to defend a tolerant society, then the tolerant will be destroyed, and tolerance with them. We should therefore claim, in the name of tolerance, the right not to tolerate the intolerant.

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