such occurrences as 'rappings,' as the movement of untouched
objects, as the lights of the seance room, are all easily feigned.
But that ignorant modern knaves should feign precisely the same
raps, lights, and movements as the most remote and unsophisticated
barbarians, and as the educated Platonists of the fourth century
after Christ, and that many of the other phenomena should be
identical in each case, is certainly noteworthy. This kind of
folklore is the most persistent, the most apt to revive, and the
most uniform. We have to decide between the theories of independent
invention; of transmission, borrowing, and secular tradition; and of
a substratum of actual fact.

Thus, either the rite of binding the sorcerer was invented, for no
obvious reason, in a given place, and thence reached the Australian
blacks, the Eskimo, the Dene Hareskins, the Davenport Brothers, and
the Neoplatonists; or it was independently evolved in each of
several remote regions; or it was found to have some actual effect--
what we cannot guess--on persons entranced. We are hampered by not
knowing, in our comparatively rational state of development, what
strange things it is natural for a savage to invent. That spirits
should knock and rap seems to us about as improbable an idea as
could well occur to the fancy. Were we inventing a form for a
spirit's manifestations to take, we never should invent _that_. But
what a savage might think an appropriate invention we do not know.
Meanwhile we have the mediaeval and later tales of rapping, some of
which, to be frank, have never been satisfactorily accounted for on
any theory. But, on the other hand, each of us might readily invent
another common 'manifestation'--the _wind_ which is said to
accompany the spirit.