There is nothing more inspiring than having a mind unfold before you. Let people teach who have a calling. It is never just a job.

To get at the meaning of a statement the logical positivist asks, "What would the world be like if it were true?" The operationist asks, "What would we have to do to come to believe it?" For the pragmatist the question is, "What would we do if did believe it?"

Mathematics is not yet capable of coping with the naïveté of the mathematician himself.

Every discipline develops standards of professional competence to which its workers are subject... Every scientific community is a society in the small, so to speak, with its own agencies of social control.

We are caught up in a paradox, one which might be called the paradox of conceptualization. The proper concepts are needed to formulate a good theory, but we need a good theory to arrive at the proper concepts.

A philosophy which speaks, even indirectly, only to philosophers is no philosophy at all; and I think the same is true if it speaks only to scientists, or only to jurists, or priests, or any other special class.

The price of training is always a certain trained incapacity: the more we know how to do something, the harder it is to learn to do it differently.