Inasmuch as the influence of superstition upon the history of society can hardly be exaggerated, it must be worth while to inquire into its origin and nature. But this inquiry leads into a quagmire of ambiguous words: and to attempt to define them for all purposes would entangle the discussion in endless controversies. So it will be best to explain merely in what sense certain words will be used in this book. “Superstition,” for example, means in common use (I think) false beliefs concerning supernatural powers, especially such as are regarded as socially injurious, and particularly as leading to obscurantism or cruelty: but it is often extended to cover beliefs of a negligible or frivolous kind, such as stories about “fairy-rings,” or the unluckiness of seeing the new moon for the first time through glass. Plainly the injuriousness of a false belief is often in dispute, and at any rate is a question of time and place. “Superstition,” then, is here used merely as a collective term for the subjects of the ensuing chapters—Magic (or the belief in occult forces) and Animism (or the belief in the activity of spirits). The consequences of a belief, again, whether good or evil, cannot affect its psychological character: in trying to explain its nature and origin, one cannot take account of its social values. The explanation of superstitions must hold of all false beliefs, whatever their utility or disutility. Nay, further, whether a belief is false or true does not necessarily affect its psychological character: for a man may hold two doctrines, one true and the other false, both derived from the sincere testimony of the same person, and he may not be able to discern any difference in the degrees of confidence with which he holds them or in their influence upon his conduct. The understanding of false belief, then, requires an examination of belief in general. Still, whilst in the mind of any given man a true and a false belief may have the same character and origin, considered generally they must surely have different origins and grounds; and to make the sequel clearer, I will anticipate its conclusions so far as to say that true beliefs seem to rest on perception or inferences verified by perception, and false beliefs seem to depend upon imagination that cannot be verified. This general statement will need several qualifications. But I rely upon it at present so far as to say that superstitions are essentially imagination-beliefs.