Do not feel certain of anything.

Neither a man nor a crowd nor a nation can be trusted to act humanely or to think sanely under the influence of a great fear.

The human animal, like others, is adapted to a certain amount of struggle for life [and] the mere absence of effort from his life removes an essential ingredient of happiness. [. . .] He forgets that to be without some of the things you want is an indispensable part of happiness.

People are zealous for a cause when they are not quite positive that it is true.

Unless a man has been taught what to do with success after getting it, the achievement of it must inevitably leave him a prey to boredom.

There are still many people in America who regard depressions as acts of God. I think Keynes proved that the responsibility for these occurrences does not rest with Providence.

You find this curious fact, that the more intense has been the religion of any period and more profound has been the dogmatic belief, the greater has been the cruelty and the worse has been the state of affairs. In the so called age of faith, when men really did believe the Christian religion in all its completeness, there was the Inquisition, with its tortures; there were millions of unfortunate women burnt as witches; and there was every kind of cruelty practised upon all sorts of people in the name of religion.