A subtle thought that is in error may yet give rise to fruitful inquiry that can establish truths of great value.

I have never written a book that didn't teach me far more than it taught my reader.

Intelligence is an extremely subtle concept. It's a kind of understanding that flourishes if it's combined with a good memory, but exists anyway even in the absence of good memory. It's the ability to draw consequences from causes, to make correct inferences, to foresee what might be the result, to work out logical problems, to be reasonable, rational, to have the ability to understand the solution from perhaps insufficient information. You know when a person is intelligent, but you can be easily fooled if you are not yourself intelligent.

John Dalton's records, carefully preserved for a century, were destroyed during the World War II bombing of Manchester. It is not only the living who are killed in war.

We mythologists know very well that myths and legends contain borrowings, moral lessons, nature cycles, and a hundred other distorting influences, and we labor to cut them away and get to what might be a kernel of truth. In fact, these same techniques must be applied to the most sober histories, for no one writes the clear and apparent truth-if such a thing can even be said to exist.

Experimentation is the least arrogant method of gaining knowledge. The experimenter humbly asks a question of nature.

After years of finding mathematics easy, I finally reached integral calculus and came up against a barrier. I realized that this was as far as I could go, and to this day I have never successfully gone beyond it in any but the most superficial way.