1. After the deaths of Plato and Aristotle, of Zeno and Epicurus, the schools founded by these philosophers continued to be known as the Academic, the Peripatetic, the Stoic, and the Epicurean. These schools, of which the Academic and the Peripatetic preceded the other two by some forty or fifty years, existed in a state of greater or of less animation until the very close of the Greek philosophy. But the period when they principally flourished was in the interval between their birth, say, in round numbers, about 300 years B.C. or somewhat earlier, and the rise of the Alexandrian or Neoplatonic philosophy about 200 years after Christ, an interval of about 500 years. During this protracted period, philosophy, although illustrated by some eminent writers, exhibited no very great accession of originality, and put forth few evidences of power. Athens continued to be the headquarters of the schools I have enumerated. But, by degrees, a more general diffusion of philosophical opinions took place. About the year 146 B.C., Greece was reduced to the condition of a Roman province. And then the arms of Rome, we may say, began to be interchanged for the arts of Athens. Philosophy now migrated for the first time to the Eternal City.