One of the chief obstacles to intelligence is credulity, and credulity could be enormously diminished by instructions as to the prevalent forms of mendacity.

All exact science is dominated by the idea of approximation.

Really high-minded people are indifferent to happiness, especially other people's.

Very few men can be genuinely happy in a life involving continual self-assertion against the skepticism of the mass of mankind, unless they can shut themselves up in a coterie and forget the cold outer world. The man of science has no need of a coterie, since he is thought well of by everybody except his colleagues. The artist, on the contrary, is in the painful situation of having to choose between being despised and being despicable.

Artists are on the average less happy than men of science.

Public opinion is always more tyrannical towards those who obviously fear it than towards those who feel indifferent to it.

Ever since men became capable of free speculation, their actions, in innumerable important respects, have depended upon their theories as to the world and human life, as to what is good and what is evil. This is true in the present day as at any former time. To understand an age or a nation, we must understand its philosophy, and to understand its philosophy we must ourselves be in some degree philosophers. There is here a reciprocal causation: the circumstances of men s lives do much to determine their philosophy, but, conversely, their philosophy does much to determine their circumstances.