" Through all my later literary life I have sought to make it plain, as the result of antecedent years spent in occult research, that the occult sciences—in all their general understanding—are paths of danger when they are not paths of simple make-believe and imposture. The importance of Éliphas Lévi’s account at large of the claims, and of their story throughout the centuries, arises from the fact (a) that he is the authoritative exponent-in-chief of all the alleged sciences; (b) that it is he who, in a sense, restored and placed them under a new and more attractive vesture, before public notice at the middle period of the nineteenth century; (c) that he claimed, as we shall see, the very fullest knowledge concerning them, being that of an adept and master; but (d) that—subject to one qualification, the worth of which will be mentioned—it follows from his long examination that Magic, as understood not in the streets only but in the houses of research concerning it, has no ground in the truth of things, and is of the region of delusion only. It is for this reason that I have translated his History of Magic, as one who reckons a not too gracious task for something which leans toward righteousness, at least in the sense of charity. The world is full at this day of the false claims which arise out of that region, and I have better reasons than most even of my readers can imagine to undeceive those who, having been drawn in such directions, may be still saved from deception. It is well therefore that out of the mouth of the masters we can draw the fullest evidence required for this purpose. In the present prefatory words I propose to shew, firstly, the nature of Éliphas Lévi’s personal claims, so that there may be no misconception as to what they were actually, and as to the kind of voice which is speaking; secondly, his original statement of the claims, nature and value of Transcendental Magic; and, thirdly, his later evidences on its phenomenal or so-called practical side, as established by its own history. "
― Éliphas Lévi , The History of Magic