INTRODUCTION
The history of medieval thought falls naturally into two broad divisions, each of which is brought to a close not by the creation of a new method or system from native resources, but by the introduction of fresh materials for study from without. The first period ended when the works of Aristotle, hitherto known only from partial and scanty versions, were translated into Latin; the second, when a knowledge of Greek letters in their own language made it impossible for men to remain satisfied with the views of ancient philosophy to which they had previously been confined and upon which their own philosophy had entirely depended. An age of eclecticism, too eager in its enjoyment of the new-found treasure to care to bind itself, as its predecessors had done, to any single authority, was then followed by an age in which the interests of theological controversy drove out every other interest, until at length in the comparative calm after the tempest of the Reformation, philosophy entered a new phase, and the medieval or traditional method was finally rejected in favour of one common in this respect to both modern and ancient speculation, that it rested upon independent thought, and regarded no authority as beyond appeal.
In the two periods of the middle ages we find nothing absolutely original; advance is measured less by the power with which men used their intellects than by the skill with which they used their materials. Still there is a difference between the periods which makes the earlier the more interesting to the student of human thought considered as apart from any specific production of it: for while the works of Aristotle were almost totally
