The Real Differences of the Three General Periods. The differences between these three periods of the reflectivelife of the European have been very real. They are not to be explained by merely political shiftings or economic changes; nor are they fully expressed as differences in literary or artistic productions. Their differences lie deeper, for they are differences of mental attitude. The history of philosophy is more profound, more difficult, and more human than any other history, because it is the record of human points of view. A good deal of sympathetic appreciation is demanded if the student takes on the attitude of mind of ancient and mediæval times. One cannot expect to be possessed of such appreciation until one has traversed the history of thought through its entire length.

The history of philosophy is an organic development from an objective to a subjective view of life, with a traditional middle period in which subjective and objective mingle. Ancient thought is properly called objective, the mediæval traditional, the modern subjective. Can we briefly suggest what these abstract terms mean? By the objectivity of ancient thought is meant that the ancient, in making his reflections upon life, starts from the universe as a whole. From this outer point of view he tries to see the interconnections between things. Nature is reality; men and gods are a part of nature. Man’s mental processes even are a part of the totality of things. Even ethically man is not an independent individual, but the member of a state. When the ancient came to make distinctions between mind and matter, he did not think of man as the knower in antithesis to matter as the object known, but he thought of mind and matter as parts of one cosmos. The antithesis in ancient thought is rather between appearances and essence, between non-realities andrealities with differing emphasis. The ancient attempts speculatively to reconstruct his world, but it is always from the point of view of the world.

By the traditionalism of mediæval thought is meant that men are controlled in their thinking by a set of authoritative doctrines from the past. In the Middle Ages, as the mediæval period is called, the independent thinking of antiquity had ceased. Men reflected and reflected deeply, but they were constrained by a set of religious traditions. Authority was placed above them and censored their thinking. The objective Christian church and its authority took the place of the objective Greek cosmos. That church had certain infallible dogma, and thinking was allowed only in so far as it clarified dogma.

On the other hand, when we say that modern thought is subjective, we refer to an entire change in the centre of intellectual gravity. The starting-point is not the world, but the individual. The universe is set over against mind (dualism), or is the creation of mind (idealism). In any case the modern man looks upon the universe as his servant, the standard of truth to be found in himself and not in something external. The subject as knower is now placed in antithesis to the object as known, and the object is not independent of the human thinking process. Reality is man rather than the cosmos. The political state is justifiable so long as it enforces the rights of the individual; religious authority is the expression of the individual conscience;physical nature is a human interpretation.[1]

Plato, Dante, and Goethe are good representatives of these three different historical periods of the human mind. How can they be understood without a philosophical appreciation of the periods in which they lived?

Table of the Subdivisions of the Three General Periods of Philosophy
1. Ancient 625 B. C.–476 A. D. Greek, 625–322 B. C. (to death of Aristotle). Cosmological, 625–480 (to Persian Wars).
Anthropological, 480–399 (to death of Socrates).
Systematic, 399–322 (to death of Aristotle).
Hellenic-Roman 322 B. C.–476 A. D. (from death of Aristotle to fall of old Rome). Ethical, 322 B. C.–1 A. D. (to beginning of Christian era).
Religious, 100 B. C.–476 A. D.
2. Mediæval 476–1453 Early Mediæval, 476–1000 (from the fall of old Rome to the beginnings of modern Europe).
Transitional Mediæval (1000–1200), (from beginnings of modern Europe to Crusades).
Classic Mediæval, 1200–1453 (from the Crusades to the fall of new Rome or Constantinople).
3. Modern 1453–modern times Renaissance, 1453–1690 (to Locke’s Essay and the English Revolution). Humanistic, 1453–1600.
Natural Science, 1600–1690.
Enlightenment, 1690–1781 (from Locke’s Essay to Kant’s Critique).
German Idealism, 1781–1831 (from Kant’s Critique to the death of Hegel).
Evolution, 1820 to the present time.

BOOK I
ANCIENT PHILOSOPHY (625 B. C.–476 A. D.)

CHAPTER I
THE EARLY GREEK IN ANCIENT PHILOSOPHY

The Divisions of Ancient Philosophy. The history of ancient philosophy falls naturally into two large divisions: pure Greek philosophy and Hellenic-Roman philosophy (or Greek philosophy in the Roman world). The date, 322 B. C., the death of Aristotle, which marks the line between these two periods, is one of the milestones of history. Alexander the Great had died in 323 B. C. The coincidence of the deaths of Aristotle and Alexander not only suggests their intimate relations as teacher and pupil during their lives, but it throws into contrast Greek civilization before and after them. Before Aristotle and Alexander culture was the product entirely of the pure Greek spirit; after them ancient culture was the complex product of many factors—of Greek and Roman civilizations, and many Oriental religions, including Christianity. Before Aristotle and Alexander, ancient culture was characterized by a love of knowledge for its own sake, by freedom from ulterior ends either of service or of use; after these great makers of history, culture became attenuated to work in the special sciences and enslaved to practical questions. Before Aristotle and Alexander, the Greek city-states had arisen to political power; after Aristotleand Alexander, Greece declined politically and was absorbed into the Roman empire.