Only a very dull man spells a word the same way twice.

Innovation is not the product of logical thought, even though the final product is tied to a logical structure.

I very rarely think in words at all. A thought comes, and I may try to express in words afterwards.

In a healthy nation there is a kind of dramatic balance between the will of the people and the government, which prevents its degeneration into tyranny.

Intelligence and genius

All the fifty years of conscious brooding have brought me no closer to answer the question, "What are light quanta?" Of course today every rascal thinks he knows the answer, but he is deluding himself.

The opinion prevailed among advanced minds that it was time that belief should be replaced increasingly by knowledge; belief that did not itself rest on knowledge was superstition, and as such had to be opposed.