Opposition is not necessarily enmity; it is merely misused and made an occasion for enmity.

As regards intellectual work it remains a fact, indeed, that great decisions in the realm of thought and momentous discoveries and solutions of problems are only possible to an individual, working in solitude.

I cannot face the idea of life without work. What would one do when ideas failed or words refused to come? It is impossible not to shudder at the thought.

A religion, even if it calls itself a religion of love, must be hard and unloving to those who do not belong to it.

Where they love they do not desire and where they desire they do not love.

A string of reproaches against other people leads one to suspect the existence of a string of self-reproaches with the same content.

Men are not gentle, friendly creatures wishing for love, who simply defend themselves if they are attacked, but ... a powerful measure of desire for aggression had to be reckoned as part of their instinctual endowment.