When Socrates formed the resolution of devoting himself to the pursuit of divine and human knowledge, the sophists, a set of arrogant philosophers, were perverting the heads and corrupting the hearts of the Grecian youth. He therefore put himself in opposition to these false guides, and went about endeavoring to instruct everybody in a wiser and better philosophy than that which prevailed. He was, in fact, an instructor of the people; and, believing himself an ambassador of God, he was occupied from the dawn of day in seeking persons whom he might teach either what is important to mankind in general, or the private circumstances of individuals. He went to the public assemblies and the most crowded streets, or entered the workshops of mechanics and artists, and conversed with the people on religious duties, on their social and political relations; on all subjects, indeed, relating to morals, and even on agriculture, war, and the arts. He endeavored to remove prevailing prejudices and errors, and to substitute right principles; to awaken their better genius in the minds of his hearers; to encourage and console them; to enlighten and improve mankind, and make them really happy. It is manifest that such a course must have been attended with great difficulties. But the serenity of Socrates was undisturbed; he was always perfectly cheerful in appearance and conversation. In the market-place and at home, among people and in the society of those whom love of truth and virtue connected more closely with him, he was always the same. It cannot be doubted that a happy physical and mental temperament contributed to produce this equanimity. But it was, likewise, a fruit of self-discipline and the philosophy he taught. He treated his body as a servant, and inured it to every privation, so that moderation was to him an easy virtue; and he retained in old age his youthful vigor, physical and mental. He was kind as a husband and a father. Though his wife, Xantippe, was a noted shrew, he viewed her as an excellent instrument of discipline, and treated her with patience and forbearance.