In the fifth century there sprang up in Greece a set of teachers who traveled about from city to city, giving instruction (for money) in philosophy and rhetoric; under which heads were included political and moral education. These men were called "Sophists" (a term early applied to wise men, such as the seven sages), and though they did not form a sect or school, they resembled one another in many respects, exerting an important, and, barring their skeptical tendencies, a healthful influence in the formation of character. Among the most eminent of these teachers were Protag'oras of Abde'ra, Gor'gias of Leontini, and Prod'icus of Ce'os. That great philosopher of a later age, Plato, while condemning the superficiality of their philosophy, characterized these men as important and respectable thinkers; but their successors, by their ignorance, brought reproach upon their calling, and, in the time of Socrates, the Sophists--so-called--had lost their influence and had fallen into contempt. "Before Plato had composed his later Dialogues," says MAHAFFY, "they had become too insignificant to merit refutation; and in the following generation they completely disappear as a class." This author thus proceeds to give the causes of their fall: "It is, of course, to be attributed not only to the opposition of Socrates at Athens, but to the subdivision of the profession of education. Its most popular and prominent branch--that of Rhetoric--was taken up by special men, like the orator An'tiphon, and developed into a strictly defined science. The Philosophy which they had touched without sounding its depths was taken up by the Socratic schools, and made the rule and practice of a life. The Politics which they had taught were found too general; nor were these wandering men, without fixed home, or familiarity with the intricacies of special constitutions, likely to give practical lessons to Greece citizens in the art of state-craft. Thus they disappear almost as rapidly as they rose--a sudden phase of spiritual awakening in Greece, like the Encyclopædists of the French." [Footnote: "History of Classical Greek literature," vol. ii., p. 63.] SOCRATES.