Aristotle, with all the wisdom of Plato before him, which he was well able to appropriate, could find no better definition of the true good of man than the full exercise or realization of the soul's faculties in accordance with its proper excellence, which was excellence of thought, speculative and practical.--Thomas Hill Green. It is pretty definitely settled, among men competent to form a judgment, that Aristotle was the best educated man that ever walked on the surface of this earth. He is still, as he was in Dante's time, the "master of those that know." It is, therefore, not without reason that we look to him, not only as the best exponent of ancient education, but as one of the worthiest guides and ensamples in education generally. That we may not lose the advantage of his example, it will be well, before we consider his educational theories, to cast a glance at his life, the process of his development, and his work. Aristotle was born about B.C. 384, in the Greek colony of Stagira in Thrace, near the borders of Macedonia. His father, Nicomachus, was a physician of good standing, the author of several medical works, and the trusted friend of Amyntas, the Macedonian King. His mother, Phæstis, was descended from the early settlers of the place. It was doubtless under his father's guidance that the boy Aristotle first became interested in those physical studies in which he was destined to do such wonderful work. Losing, however, both his parents at an early age, he came under the charge of Proxenus, of Atarneus, who appears to have done his duty by him. At the age of eighteen he came to Athens for his higher education, and entered the school of Plato in the Academy. Here he remained for nearly twenty years, listening to Plato, and acquiring those vast stores of information which in later life he worked up into lectures and scientific treatises. Nothing escaped him, neither art, science, religion, philosophy, nor politics. He seems, being well off, to have begun early to collect a library, and to aim at encyclopædic knowledge. About his methods of study we know very little; but we hear that at times he assisted Plato in his work and was very careful of his own attire. It is clear that, in course of time, he rose in thought above the teachings of his master, and even rejected the most fundamental of them, the doctrine of self-existent ideas. But he never lost respect for that master, and when the latter died, he retired with Xenocrates, son of the new head of the Academy, to Atarneus, the home of his old guardian Proxenus, and of his fellow-Academic, Hermias, now king or tyrant of the place. Here he remained for three years, in the closest intimacy with his friend, until the latter was treacherously murdered by the Persians. He then crossed over to Mytilene, taking with him Pythias, Hermias' sister or niece, whom he had married, and to whom he was deeply devoted. He erected in Delphi a statue to his dead friend,