The circumstance mentioned makes it in no science so necessary as in the history of Philosophy to commence with an Introduction, and in it correctly to define, in the first place, the subject of the history about to be related. For it may be said, How should we begin to treat a subject, the name of which is certainly mentioned often enough, but of whose nature we as yet know nothing? In treating the history of Philosophy thus, we could have no other guidance than that of seeking out and taking up whatever has received the name of Philosophy, anywhere or any time. But in fact, when the Notion of Philosophy is established, not arbitrarily but in a scientific way, such treatment becomes the science of Philosophy itself. For in this science the peculiar characteristic is that its Notion forms the beginning in appearance merely, and it is only the whole treatment of the science that is the proof, and indeed we may say the finding of its Notion; and this is really a result of that treatment. In this Introduction the Notion of the science of Philosophy, of the subject of its history, has thus likewise to be set forth. At the same time, though this Introduction professes to relate to the history of Philosophy only, what has just been said of Philosophy on the whole, also holds good. What can be said in this Introduction is not so much something which may be stated beforehand, as what can be justified or proved in the treatment of the history. These preparatory explanations are for this reason only, not to be placed in the category of arbitrary assumptions. But to begin with stating what in their justification are really results, can only have the interest which may be possessed by a summary, given in advance, of the most general contents of a science. It must serve to set aside many questions and demands which might, from our ordinary prejudices, arise in such a history. INTRODUCTION THERE are various aspects under which the History of Philosophy may possess interest. We shall find the central point of this interest in the essential connection existing between what is apparently past and the present stage reached by Philosophy. That this connection is not one of the external considerations which may be taken into account in the history of Philosophy, but really expresses its inner character: that the events of this history, while they perpetuate themselves in their effects like all other events, yet produce their results in a special way—this it is which is here to be more clearly expounded. What the history of Philosophy shows us is a succession of noble minds, a gallery of heroes of thought, who, by the power of Reason, have penetrated into the being of things, of nature and of spirit, into the Being of God, and have won for us by their labours the highest treasure, the treasure of reasoned knowledge.