I want to write a historical preface to the treatment of a theme much talked of in our contemporary faculties of sociology and history. The theme is not philosophical, in the common tradition of this Gifford foundation. Its matter concerns students of human society; especially students of society in the relatively recent past. The historian starts to feel scruple when confronted by the will of Lord Gifford. For Lord Gifford wanted to know what was true, or wanted men to confirm what he already believed to be true. The historians of the last hundred years have eschewed, or have looked as though they eschewed, any attempt to answer questions on whether a belief is true, and have devoted their endeavour to questions appropriate to their discipline, why belief arose, how it was believed, how its axioms affected society, and in what manner it faded away. Lord Gifford preferred lecturers who prove that witches are powerless. Historians refrained from any such bold assertion, and asked themselves only how men came to think witches powerless when their power looked obvious. And therefore the historian, confronted by Lord Gifford's will, suffers a twinge of scruple.

A student of this theme, however, may console himself that he is nearer to Lord Gifford than the fringe of some subsidiary enquiry which can be relegated to a trivial appendix in a future system of philosophy.