Have no respect for the authority of others, for there are always contrary authorities to be found

Insight, untested and unsupported, is an uncertain guarantee of the truth.

We love our habits more than our income, often more than our life.

Prophets, mystics, poets, scientific discoverers are men whose lives are dominated by a vision; they are essentially solitary men . . . whose thoughts and emotions are not subject to the dominion of the herd.

Laughter is the most inexpensive and most effective wonder drug. Laughter is a universal medicine.

My own view on religion is that of Lucretius. I regard it as a disease born of fear and as a source of untold misery to the human race. I cannot, however, deny that it has made some contributions to civilisation. It helped in early days to fix the calendar, and it caused Egyptian priests to chronicle eclipses with such care that in time they became able to predict them. These two services I am prepared to acknowledge, but I do not know of any others.

To be able to fill leisure intelligently is the last product of civilization, and at present very few people have reached this level.