Learn to laugh at yourselves as one must laugh!

For some natures, changing their opinions is just as much a requirement of cleanliness as changing their clothes: for others, however, it is merely a requirement of vanity.

A degree of culture, and assuredly a very high one, is attained when man rises above superstitions and religious notions and fears, and, for instance, no longer believes in guardian angels or in original sin, and has also ceased to talk of the salvation of his soul.

It is a distinction to have many virtues, but a hard lot.

Life is an instinct for growth, for survival, for the accumulation of forces, for power.

Not to him who is offensive to us are we most unfair, but to him who doth not concern us at all.

People to whom their daily life appears too empty and monotonous easily grow religious; this is comprehensible and excusable, only they have no right to demand religious sentiments from those whose daily life is not empty and monotonous.