101. The most ordinary mode of apparition is that which takes place in sleep,
through dreams; such apparitions are
called visions. It does not enter into the plan of our present work to examine all the
peculiarities that are presented by dreams ; we will merely state that they may be: - the
actual sight of objects present or absent; a retrospective view of the past; and, in some
exceptional cases, a presentiment of the future. Dreams are also, in many cases,
allegorical pictures which spirits bring before our eyes ; the good, in order to give us
useful warnings and salutary counsels; the imperfect, in order to lead us into error, or to
flatter our passions. The theory we are about to place before the reader is applicable to
dreams, as it is to all cases of apparitions. (See The Spirits' Book, N°. 400; et seq.). As
for what is vulgarly called " the interpretation of dreams," we should consider it to be
an insult to the common sense of our readers, were we to attempt to point out its
absurdity.