Why should one take any serious interest in such a bizarre character as Aleister Crowley? Even if scholars have now begun to show an interest in him and the number of serious studies devoted to him is slowly increasing, it is still easier to find books that describe him in a sensationalist manner, as a bogeyman or a charlatan or both – just as it was the case during his lifetime. Sometimes even authors who have already done courageous pioneering work in the critical and historical study of esoteric movements, and who have had to defend the subjects of their research from suspicion and from attempts at marginalization, have not held back from voicing expressions of contempt when considering Crowley. A significant example can be found in Gershom Scholem's Major Trends in Jewish Mysticism, a milestone in the research on Jewish esotericism. Scholem describes Crowley's use of certain Kabbalistic ideas as “highly coloured humbug” and takes a sharper tone in a later note: “No words need be wasted on the subject of Crowley's “Kabbalistic' writings.”

With the emergence of new fields of research, such as the history of Western esotericism and the study of new religious movements, scholars have begun to delve beyond Crowley's personality and to study him more methodically and attentively as an author. It has been realized, in fact, that Crowley represents an essential source for the understanding of a broad category of new religious movements, ranging from neo-paganism to Satanism.