Men who are orthodox when they are young are in danger of being middle-aged all their lives.

Successful democratic politicians are insecure and intimidated men. They advance politically only as they placate, appease, bribe, seduce, bamboozle, or otherwise manage to manipulate the demanding and threatening elements in their constituencies. The decisive consideration is not whether the proposition is good but whether it is popular -- not whether it will work well and prove itself but whether the active talking constituents like it immediately. Politicians rationalize this servitude by saying that in a democracy public men are the servants of the people.

The radical novelty of modern science lies precisely in the rejection of the belief... that the forces which move the stars and atoms are contingent upon the preferences of the human heart.

It is often very illuminating...to ask yourself how you got at the facts on which you base your opinion. Who actually saw, heard, felt, counted, named the thing, about which you have an opinion?

Because the results are expressed in numbers, it is easy to make the mistake of thinking that the intelligence test is a measure like a foot ruler or a pair of scales. It is, of course, a quite different sort of measure. Intelligence is not an abstraction like length and weight; it is an exceedingly complicated notion - which nobody has yet succeeded in defining.

What a myth never contains is the critical power to separate its truth from its errors.

The study of error is not only in the highest degree prophylactic, but it serves as a stimulating introduction to the study of truth.