The same relation exists between merchant and pirate, who for a long period are one and the same person: where the one function appears to them inadvisable, they exercise the other.
Out of damp and gloomy days, out of solitude, out of loveless words directed at us, conclusions grow up in us like fungus: one morning they are there, we know not how, and they gaze upon us, morose and gray. Woe to the thinker who is not the gardener but only the soil of the plants that grow in him.
One unconsciously takes it for granted that doer and sufferer think and feel alike, and according to this supposition we measure the guilt of the one by the pain of the other.
So far there has been no philosopher in whose hands philosophy has not grown into an apology for knowledge; on this point, at least, every one is an optimist, that the greatest usefulness must be ascribed to knowledge. They are all tyrannized over by logic, and this is optimism in its essence.
Whereas the man of action binds his life to reason and its concepts so that he will not be swept away and lost, the scientific investigator builds his hut right next to the tower of science so that he will be able to work on it and to find shelter for himself beneath those bulwarks which presently exist.