The Difficulty in the Study of Modern Philosophy. Beside the great spans of ancient and mediæval civilizations, the 450 years of the modern period seem brief. The road is indeed relatively short from mediæval times to the century in which we live, and yet it proves difficult to the student who travels it for the first time. Even for the modern mind the study of modern philosophy is inherently more difficult than that of the ancient and mediæval. The preceding periods present new points of view, but these, once attained, lead along comparatively easy ways. The chief difficulty of the preceding periods is overcome when their peculiar view of things is gained; but the student of modern philosophy is confronted with difficulties all along the way. In the first place, modern philosophy is very complex because it is a conflict of various aspirations. It has neither the objectivity of ancient thought nor the logical consistency of mediæval thought. It arises fromsubjective motives, whose shadings are difficult to trace. The task is rendered harder by the fact that intimations of the problems in the history of modern philosophy are on the whole present in the beginner’s mind; and yet at the same time his mind possesses, besides these, many mediæval notions as well. For the student to pass successfully through the entire length of modern thought from Cusanus to Spencer means, therefore, two things for him: (1) he must gain an insight into the depth and significance of his own half-formed ideas; (2) he must transcend or give up entirely his mediæval notions. If therefore philosophy represents the epoch that produces it,—either as the central principle or as the marginal and ulterior development of that epoch,—the modern can come to an understanding of the history of modern philosophy only by coming to an understanding of himself and his own inner reflections.
This will explain why the short period of modern thought is traditionally divided into comparatively many periods. These subordinate periods ring out the changes through which the modern man feels that he himself has blindly passed in his inner life. Modern philosophy is no more local and temporary than the ancient; it is no less a part of a social movement; but the modern man is more alive to the differentiations of modern thought than he is to those of antiquity.
The Periods of Modern Philosophy. The divisions of the history of modern philosophy are as follows:—
1. The Renaissance (1453–1690)—from the end of the Middle Ages to the publication of Locke’s Essay on the Human Understanding.
2. The Enlightenment (1690–1781)—to the publication of Kant’s Critique of Pure Reason.
3. German Philosophy (1781–1831)—to the death of Hegel.
4. The Nineteenth Century Philosophy (1820–the present time).
The Renaissance, the first period, covers more than half of the length of modern times. It is sometimes called the springtime of modern history, although it is longer than all the other seasons together. It is to be noted that two epoch-making books form the dividing lines between the first three periods. The transition from the Renaissance to the Enlightenment is signalized by Locke’s great Essay on the Human Understanding, which expressed for one hundred years the political and philosophical opinions of western Europe. The transition from the Enlightenment to German Philosophy was in its turn signalized by the appearance of Kant’s Critique of Pure Reason, and this book may be said to have been fundamental to human thinking ever since. There is one point further to be noticed in these divisions, and that is the overlapping of the last two periods. German philosophy ends practically with the death of Hegel in 1831, and the modern Evolution movement began at least ten years before, about 1820. No great philosophical treatise marks the division here, for the Evolution movement had its beginnings in German philosophy and in the discoveries and practical inventions of natural science. Evolution, however, became a reaction upon the last phases of German philosophy, and then formed a distinct movement. The book that formulated the Evolution movement most fully appeared several years after the theory was under way. This was Darwin’s Origin of Species, published in 1859. Locke’s Essay and Kant’s Critique are thereforethe most influential philosophical interpretations of the history of modern times since its early beginnings in the Renaissance.
The Causes of the Decay of the Civilization of the Middle Ages. The social structure of the mediæval time weakened and broke apart, in the first place because of certain inherent defects in its organism; in the second place because of some remarkable discoveries, inventions, and historical changes. We may call these (1) the internal causes and (2) the external causes of the fall of the civilization of the Middle Ages.
(a) The Internal Causes were inherent weaknesses in mediæval intellectual life, and alone would have been sufficient to bring mediæval society to an end.