ARISTOTLE, the greatest and most influential of all the Greek philosophers, was born at the town of Stageira in the year 384 B.C. His father, Nikomachus, was the friend and physician of Amyntas II, king of Macedonia, father of Philip and grandfather of Alexander the Great. Aristotle's early education seems to have been directed toward the same profession, but it would appear that he early abandoned this intention, and aspired to that cultivation of universal knowledge for its own sake, in which he obtained a distinction without parallel in the history of the human race. In his 18th year he left Stageira for Athens, then the intellectual center of Greece and of the civilized world. Here he became the pupil of Plato, but soon made his master aware of the remarkable penetration and reach of his intellect, for we are told that Plato spoke of Aristotle as the "Intellect of the School." He remained at Athens twenty years, during which the only facts recorded, in addition to his studying with Plato, are, that he set up a class in rhetoric, and that in so doing, he became the rival of the celebrated orator and rhetorical reader, Isocrates. Upon the death of Plato, (347 B.C.,) Aristotle left Athens and went to the Mysian town of Atarneus, and thence to Mitylene. After two years stay at the latter place, he was invited (in the year 342 B.C.,) by Philip to Macedonia, to educate his son Alexander. When Alexander commenced his expedition into Asia, (334 B.C.,) Aristotle returned to Athens. Now at the age of fifty, he entered on the final epoch of his life; he opened a school called the Lyceum, from its proximity to the temple of Apollo Lyceius. From his practice of walking up and down in the garden during his lectures, arose the name of his school and sect, the Peripatetic. He may now be supposed to have composed his principal writings, but there is nothing known of the dates of any of them. This crowning period of his life lasted twelve years. After the death of Alexander, the anti-Macedonian party at Athens obtained an ascendency, and an accusation was prepared against Aristotle, the charge being impiety. With the fate of Socrates before his eyes, he chose a timely escape, and in the beginning of 322 B.C., took refuge at Chalcis, in Euboea, where in the autumn of the same year he died, aged 62.
The writings of Aristotle may be said to have embraced the whole circle of knowledge of his time. Many of them are lost; of those that remain the most important are the "Organon," or "Logic," "Rhetoric," "Poetics" and "Meteorology." His Organon or Logic is his complete development of formal reasoning, and is the basis and nearly the whole substance of syllogistic or scholastic logic. This science he almost entirely created, He may also be said to have created natural science. In his great work on Animals he amassed a stock of genuine observations, and introduced a method of classification, which continues to this day. His treatises on Rhetoric and Poetics were the earliest development of the Philosophy of Criticism, and still continue to be studied. The same remark is applicable to his elaborate work on Ethics.
The philosophy of Aristotle differed from that of Plato on many points, especially in the fundamental doctrine termed the Theory of Ideas. The Platonic "ideas" or "forms," were conceived as real existences. Aristotle was opposed to this doctrine; his whole method was in marked contrast to that of Plato, and consisted in the principle that all philosophy must be founded on the observation of facts. He first established the philosophical notions of "matter," "form," "time" and "space," and first argued the necessary existence of God as the ultimate cause or all things. No other philosopher can be named whose influence has been so far-reaching and so long continued.