The truth is a snare: you cannot have it, without being caught. You cannot have the truth in such a way that you catch it, but only in such a way that it catches you.

It is very important in life to know when your cue comes.

Leap of faith – yes, but only after reflection

Whoever has the world's treasures has them no matter how he got them. In the world of the spirit it is otherwise.

But doubt is wily and cunning and never, as it is sometimes said to be, loud or defiant. It is unassuming and sly, not bold or assertive - and the more unassuming, the more dangerous.

Knowledge is an attitude, a passion, actually an illicit attitude. For the compulsion to know is like dipsomania, erotomania, and homicidal mania, in producing a character that is out of balance. It is not at all that the scientist goes after the truth.

The difference between a man who faces death for the sake of an idea and an imitator who goes in search of martyrdom is that whilst the former expresses his idea most fully in death it is the strange feeling of bitterness which comes from failure that the latter really enjoys; the former rejoices in his victory, the latter in his suffering.