the presentations of this book as the out-pourings of a fantasy
run wild or as dreamy thought-pictures. Yet all that can be said in this
respect is contained in the book itself, and it is explicitly shown that
sane and earnest thought not only can but _must_ be the touch-stone of all
the facts presented. Only one who submits what is here advanced to logical
and adequate examination, such as is applied to the facts of natural
science, will be in a position to decide for himself how much reason has
to say in the matter.

After saying this much about those who may at first be inclined to take
exception to this work, we may perhaps be permitted to address a few words
to those on whose sympathetic attention we can rely. These will find all
broad essentials contained in the first chapter, "Concerning the Nature of
Occult Science." A word, however, must here be added. Although this book
deals with investigations carried beyond the confines of intellect limited
to the world of the senses, yet nothing has been asserted except what can
be grasped by any person possessed of unprejudiced reasoning powers backed
by a healthy sense of truth, and who is at the same time willing to turn
these gifts to the best account; and the writer emphatically wishes it to
be understood that he hopes to appeal to readers who will not be content
with merely accepting on "blind faith" the matters presented, but who will
take the trouble to test them by the light of their own understanding and
by the experiences of their own lives. Above all, he desires _cautious_
readers, who will allow themselves to be convinced only by what can be
logically justified. The writer is well aware that his work would be worth
nothing were its value to rest on blind belief; it is valuable only in the
degree to which it can be justified by unbiased reason. It is an easy
thing for "blind faith" to confound folly and superstition with truth, and
doubtless many, who have been content to accept the supersensible on mere
faith, will be inclined to think that this book makes too great demands
upon their powers of thought. It is not a question of merely making
certain communications, but rather of presenting them in a manner
consistent with a conscientious view of the corresponding plane of life;
for this is the plane upon which the loftiest matters are often handled
with unscrupulous charlatanism, and where knowledge and superstition come
into such close contact as to be liable to