"But how do you know that men of genius, in whom the whole world puts its faith, haven't seen ghosts too? Nowadays scientists say genius is akin to madness. My friend, only the mediocre, the common herd are healthy and normal. Thoughts about an age of neurosis, over- work, degeneracy and so on can seriously worry only those for whom the purpose of life lies in the present - that is, the common herd."