CHAPTER II "AUXILIARY SCIENCES" Let us suppose that the preliminary searches, treated of in the preceding chapter, have been made methodically and successfully; the greater part, if not the whole, of the documents bearing on a given subject have been discovered and made available. Of two things one: either these documents have been already subjected to critical elaboration, or they are in the condition of raw material; this is a point which must be settled by "bibliographical" researches, which also, as we have already observed, form part of the inquiries which precede the logical part of the work. In the first case, where the documents have already gone through a process of elaboration, it is necessary to be in a position to verify the accuracy of the critical work; in the second case, where the documents are still raw material, the student must do the critical work himself. In both cases certain antecedent and auxiliary knowledge of a positive kind, _Vor-und Hülfskenntnisse_, as they are called, are every whit as indispensable as the habit of accurate reasoning; for if, in the course of critical work, it is possible to go wrong through reasoning badly, it is also possible to go wrong out of pure ignorance. The profession of a scholar or historian is, moreover, similar in this respect to all other professions; it is impossible to follow it without possessing a certain equipment of technical notions, whose absence neither natural aptitude nor even method can make good. In what, then, does the technical _apprenticeship_ of the scholar or the historian consist? Or, to employ language which, though inappropriate, as we shall endeavour to show, is in more common use: what, in addition to the knowledge of repertories, are the "auxiliary sciences" of history?