Now, ordinary dreams, in which the dreamer seemed to see persons who were
really remote; would supply to the savage reasoner a certain amount of
affirmative evidence. It is part of Mr. Tylor's contention that savages
(like some children) are subject to the difficulty which most of us may
have occasionally felt in deciding 'Did this really happen, or did I dream
it?' Thus, ordinary dreams would offer to the early thinker some
evidence that other men's souls could visit his, as he believes that his
can visit them.

But men, we may assume, were not, at the assumed stage of thought, so
besotted as not to take a great practical distinction between sleeping
and waking experience on the whole. As has been shown, the distinction
is made by the lowest savages of our acquaintance. One clear _waking_
hallucination, on the other hand, of the presence of a person really
absent, could not but tell more with the early philosopher than a score of
dreams, for to be easily forgotten is of the essence of a dream. Savages,
indeed, oddly enough, have hit on our theory, 'dreams go by contraries.'
Dr. Callaway illustrates this for the Zulus, and Mr. Scott for the
Mang'anza. Thus they _do_ discriminate between sleeping and waking. We
must therefore examine _waking_ hallucinations in the field of actual
experience, and on such recent evidence as may be accessible. If these
hallucinations agree, in a certain ratio, beyond what fortuitous
coincidence can explain, with real but unknown events, then such
hallucinations would greatly strengthen, in the mind of an early
thinker, the savage theory that a man at a distance may, voluntarily or
involuntarily, project his spirit on a journey, and be seen where he is
not present.

When Mr. Tylor wrote his book, the study of the occasional waking