One of the most powerful of all our passions is the desire to be admired and respected.

Although this may seem a paradox, all exact science is based on the idea of approximation. If a man tells you he knows a thing exactly, then you can be safe in inferring that you are speaking to an inexact man.

Stupidity and unconscious bias often work more damage than venality.

The resistance to a new idea increases by the square of its importance.

Life is nothing but a competition to be the criminal rather than the victim.

A good world needs knowledge, kindliness, and courage; it does not need a regretful hankering after the past or a fettering of the free intelligence by the words uttered long ago by ignorant men.

If you think your belief is based upon reason, you will support it by argument rather than by persecution, and will abandon it if the argument goes against you. But if your belief is based upon faith, you will realize that argument is useless, and will therefore resort to force either in the form of persecution or by stunting or distorting the minds of the young in what is called 'education.'