But if thought is to become the possession of many, not the privilege of the few, we must have done with fear. It is fear that holds men back - fear lest their cherished beliefs should prove delusions, fear lest the institutions by which they live should prove harmful, fear lest they themselves should prove less worthy of respect than they have supposed themselves to be.

... the word "theory" ... was originally an Orphic word, which Cornford interprets as "passionate sympathetic contemplation" ... For Pythagoras, the "passionate sympathetic contemplation" was intellectual, and issued in mathematical knowledge ... To those who have reluctantly learnt a little mathematics in school this may seem strange; but to those who have experienced the intoxicating delight of sudden understanding that mathematics gives, from time to time, to those who love it, the Pythagorean view will seem completely natural.

In all affairs it's a healthy thing now and then to hang a question mark on the things you have long taken for granted.

I am not myself in any degree ashamed of having changed my opinions.

The institution of representative government to us seems an essential part of democracy, but the ancients never thought of it. Its immense merit was that it enabled a large constituency to exert indirect power, and thus made possible the distribution of political responsibility throughout the great states of modern times.

Anything you're good at contributes to happiness.

To a mind of sufficient intellectual power, the whole of mathematics would appear trivial, as trivial as the statement that a four-footed animal is an animal.