The most eminent of the contemporaries of Demosthenes were Isaeus (420-348 B.C.), an artificial and elaborate orator; Lycurgus (393-328 B.C.), a celebrated civil reformer of Athens; Hypereides, contemporary of Lycurgus; and, above all, Aeschines (389-314 B.C.), the great rival of Demosthenes, of whose numerous speeches only three have been preserved. At a later period we find two schools of rhetoric, the Attic, founded by Aeschines, and the Asiatic, established by Hegesias of Magnesia. The former proposed as models of oratory the great Athenian orators, the latter depended on artificial manners, and produced speeches distinguished rather by rhetorical ornaments and a rapid flow of diction than by weight and force of style. In the historical department, Thucydides (471-391 B.C.) began an entirely new class of historical writing. While Herodotus aimed at giving a vivid picture of all that fell under the cognizance of the senses, and endeavored to represent a superior power ruling over the destinies of princes and people, the attention of Thucydides was directed to human action, as it is developed from the character and situation of the individual. His history, from its unity of action, may be considered as a historical drama, the subject being the Athenian domination over Greece, and the parties the belligerent republics. Clearness in the narrative, harmony and consistency of the details with the general history, are the characteristics of his work; and in his style he combines the concise and pregnant oratory of Pericles with the vigorous but artificial style of the rhetoricians. Demosthenes was so diligent a student of Thucydides that he copied out his history eight times. Xenophon (445-391 B.C.) may also be classed among the great historians, his name being most favorably known from the "Anabasis," in which he describes the retreat of the ten thousand Greek mercenaries in the service of Cyrus, the Persian king, among whom he himself played a prominent part. The minuteness of detail, the picturesque simplicity of the style, and the air of reality which pervades it, have made it a favorite with every age. In his memorials of Socrates, he records the conversations of a man whom he had admired and listened to, but whom he did not understand. In the language of Xenophon we find the first approximation to the common dialect, which became afterwards the universal language of Greece. He wrote several other works, in which, however, no development of one great and pervading idea can be found; but in all of them there is a singular clearness and beauty of description.