The thinker or the artist will never sit calmly on Olympian heights, as we have become accustomed to represent them to ourselves. The thinker or the artist should suffer in company with the people, in order that he may find salvation or consolation. Besides this, he will suffer because he is always and eternally in turmoil and agitation: he might decide and say that that which would confer welfare on men, would free them from suffering, would afford them consolation; but he has not said so, and has not presented it as he should have done; he has not decided, and he has not spoken; and to-morrow, possibly, it will be too late,--he will die. And therefore suffering and self-sacrifice will always be the lot of the thinker and the artist. Not of this description will be the thinker and artist who is reared in an establishment where, apparently, they manufacture the learned man or the artist (but in point of fact, they manufacture destroyers of science and of art), who receives a diploma and a certificate, who would be glad not to think and not to express that which is imposed on his soul, but who cannot avoid doing that to which two irresistible forces draw him,--an inward prompting, and the demand of men. There will be no sleek, plump, self-satisfied thinkers and artists. Spiritual activity, and its expression, which are actually necessary to others, are the most burdensome of all man's avocations; a cross, as the Gospels phrase it. And the sole indubitable sign of the presence of a vocation is self-devotion, the sacrifice of self for the manifestation of the power that is imposed upon man for the benefit of others. It is possible to study out how many beetles there are in the world, to view the spots on the sun, to write romances and operas, without suffering; but it is impossible, without self-sacrifice, to instruct people in their true happiness, which consists solely in renunciation of self and the service of others, and to give strong expression to this doctrine, without self-sacrifice. Christ did not die on the cross in vain; not in vain does the sacrifice of suffering conquer all things. But our art and science are provided with certificates and diplomas; and the only anxiety of all men is, how to still better guarantee them, i.e., how to render the service of the people impracticable for them. True art and true science possess two unmistakable marks: the first, an inward mark, which is this, that the servitor of art and science will fulfil his vocation, not for profit but with self-sacrifice; and the second, an external sign,--his productions will be intelligible to all the people whose welfare he has in view.