connected members, with reference as well to imaginary as to actually existing constitutions. The constitution is the arrangement of the powers in the state—the soul of the state, as it were,—according to which the sovereignty is determined. The laws are the determining principles, according to which the dominant body governs and restrains those who would, and punishes those who do, transgress them. He defines three kinds of constitutions, each of them having a corresponding perversion:—a republic, arising from the principle of equality; this at times degenerates into democracy; monarchy, and aristocracy, which arise from principles of inequality, founded on the preponderance of external or internal strength and wealth, and which are apt to degenerate into tyranny and oligarchy. The education of youth he considers as a principal concern of the state, in order that, all the individual citizens being trained to a virtuous life, virtue may become predominant in all the spheres of political life; and, accordingly, by means of politics the object is realized of which ethics are the groundwork, namely, human happiness, depending on a life in accordance with virtue.
Heraclides Ponticus, as he is usually called, was, as his name denotes, a native of Pontus. He migrated to Athens, where he became a disciple of Plato, who, while absent in Sicily, entrusted him with the care of his school.
Speusippus was the nephew of Plato, and succeeded him as President of the Academy; but he continued so but a short time, and, within eight years of the death of Plato, he died at Athens, b.c. 339. He refused to recognise the Good as the ultimate principle; but, going back to the older theologians, maintained that the origin of the universe was to be set down indeed as a cause of the Good and Perfect, but was not the Good and Perfect itself; for that was the result of generated existence or development, just as plants are of the seeds. When, with the Pythagoreans, he reckoned the One in the series of good things, he probably thought of it only in opposition to the Manifold, and wished to point out that it is from the One that the Good is to be derived. He appears, however, (see De Nat. Deor. i. 13,) to have attributed vital
