When a man grows old he must consciously remain at a certain stage.
It does not become an old man to run after the fashion, either in thought or in dress. But he must know where he is, and what the others are aiming at.
What is called fashion is the tradition of the moment. All tradition carries with it a certain necessity for people to put themselves on a level with it.
We have long been busy with the critique of reason. I should like to see a critique of common-sense. It would be a real benefit to mankind if we could convincingly prove to the ordinary intelligence how far it can go; and that is just as much as it fully requires for life on this earth.
The thinker makes a great mistake when he asks after cause and effect: they both together make up the indivisible phenomenon.
All practical men try to bring the world under their hands; all thinkers, under their heads. How far each succeeds, they may both see for themselves.
Shall we say that a man thinks only when he cannot think out that of which he is thinking?
What is invention or discovery? It is the conclusion of what we were looking for.
It is with history as with nature and with everything of any depth, it may be past, present, or future: the further we seriously pursue it, the more difficult are the problems that appear. The man who is not afraid of them, but attacks them bravely, has a feeling of higher culture and greater ease the further he progresses.
Every phenomenon is within our reach if we treat it as an inclined plane, which is of easy ascent, though the thick end of the wedge may be steep and inaccessible.
If a man would enter upon some course of knowledge, he must either be deceived or deceive himself, unless external necessity irresistibly determines him. Who would become a physician if, at one and the same time, he saw before him all the horrible sights that await him?
How many years must a man do nothing before he can at all know what is to be done and how to do it!
Duty: where a man loves what he commands himself to do.
When Madame Roland was on the scaffold, she asked for pen and paper, to note the peculiar thoughts that hovered about her on the last journey. It is a pity they were refused, for in a tranquil mind thoughts rise up at the close of life hitherto unthinkable; like blessed inward voices, alighting in glory on the summits of the past.