Uncertainty that comes from knowledge (knowing what you don't know) is different from uncertainty coming from ignorance.

It’s a poor atom blaster that won’t point both ways.

I have written 240 books on a wide variety of topics. . . . Some of it I based on education I received in my school, but most of it was backed by other ways of learning - chiefly in the books I obtained in the public library.

There is as yet insufficient data for a meaningful answer.

I do not fear computers. I fear the lack of them.

Never let your sense of morals get in the way of doing what's right.

It was obvious that bigotry was never a one-way operation, that hatred bred hatred!