Necessity of a Working Hypothesis.–The Newtonian Hypothesis.–The
Atomic Theory.–A Psychological Hypothesis necessary.–Theories
of Hypnotism and Mesmerism.–Spiritism.–Mental
Therapeutics.–Liébault’s Law of Suggestion.–Duality of Mind.–A
Working Hypothesis for Psychology formulated.–Its Three Terms.

Substantial progress in any science is impossible in the absence
of a working hypothesis which is universal in its application to
the phenomena pertaining to the subject-matter. Indeed, until such
an hypothesis is discovered and formulated, no subject of human
investigation can properly be said to be within the domain of the exact
sciences. Thus, astronomy, previous to the promulgation of Kepler’s
Laws and the formulation of the Newtonian hypothesis of gravitation,
was in a state of chaos, and its votaries were hopelessly divided by
conflicting theories. But the moment Newton promulgated his theorem a
revolution began which eventually involved the whole scientific world.
Astronomy was rescued from the domain of empiricism, and became an
exact science. What the Newtonian hypothesis did for astronomy, the
atomic theory has done for chemistry. It enables one skilled in that
science to practise it with a certainty of results in exact proportion
to his knowledge of its principles and his skill in applying them to
the work in hand. He knows that if he can combine hydrogen and oxygen,
in the proportion of two atoms of the former to one of the latter,
water will be the result. He knows that one atom, or part, of oxygen
and one of carbon combined under heat will produce carbonic oxide,–a
poisonous gas; that the addition of another atom, or part, of oxygen
will produce carbonic anhydride (dioxide),–a harmless gas; and so on
throughout the vast realm of chemical combinations.

The fact that the literal correctness of a given hypothesis is not
demonstrable except by results, in no wise militates against its
value in the domain to which it belongs. Indeed, it would cease to
be a hypothesis the moment it were demonstrated. Newton’s theorem
is undemonstrable except from its results. Its correspondence,
however, with every known fact, the facility with which astronomical
calculations can be made, and the precision with which every result can
be predicted, constitute a sufficient demonstration of its substantial
correctness to inspire the absolute confidence of the scientific
world. No one would hesitate to act in the most important concerns of
life–nay, to stake his very existence–upon calculations based upon
Newton’s hypothesis. Yet there are not found wanting men who deny or
doubt its abstract correctness. Volumes have been written to disprove
it. But as no one has yet discovered a fact or witnessed a phenomenon
outside of its domain, the world refuses to surrender its convictions.
When such a fact is discovered, then, and not till then, will there
arise a necessity for revising the “Principia.” It is a trite and true
saying that one antagonistic fact will destroy the value of the finest
theory ever evolved.

It is equally impossible to demonstrate the abstract correctness of
the atomic theory. An appeal to the evidence found in uniform results
is all that is possible to one who would give a reason for the faith
that is in him. No one ever saw, felt, tasted, or smelled an atom.
It is beyond the reach of the senses; nor is it at all probable that
science or skill will ever be able to furnish instrumental aids capable
of enabling man to take cognizance of the ultimate unit of matter. It
exists for man only in hypothesis. Nevertheless, the fact remains,
that in all the wide range of human investigation there is not a more
magnificent generalization, nor one more useful to mankind in its
practical results, than the atomic theory. Yet there are those who
doubt its abstract correctness, and labor to disprove the existence
of the atom. If the ultimate object of chemical science were to
demonstrate the existence of the atom, or to seize it and harness it
to the uses of mankind, it might be worth while to set the chemical
fraternity right by demonstrating its non-existence. If the practice of
chemistry on the basis of the theory were defective in its practical
results, or failed in universal application, it would then be the duty
of scientists to discard it entirely, and to seek a better working

The most that can be said of any scientific hypothesis is, that whether
true in the abstract or not, everything happens just as though it
were true. When this test of universality is applied, when no known
fact remains that is unexplained by it, the world is justified in
assuming it to be true, and in deducing from it even the most momentous
conclusions. If, on the contrary, there is one fact pertaining to the
subject-matter under investigation which remains outside the domain
of the hypothesis, or which is unexplained by it, it is indubitable
evidence that the hypothesis is unsafe, untrue, and consequently
worthless for all practical purposes of sound reasoning. Thus, Sir
Isaac Newton, after having formulated his theorem, threw it aside as
worthless, for a time, upon making the discovery that the moon, in its
relations with the earth, apparently did not come within the terms of
his hypothesis. His calculations were based upon the then accepted
estimate of the length of a degree of latitude. This estimate having
been corrected by the careful measurements of Picard, Newton revised
his figures, and found that the supposed discrepancy did not exist.
The last doubt in his mind having been thus set at rest, he gave to
the world a theorem which rendered possible substantial progress in
astronomical science.

In the field of psychological investigation a satisfactory working
hypothesis has never been formulated. That is to say, no theory has
been advanced which embraces all psychological phenomena. Many theories
have been advanced, it is true, to account for the various classes of
phenomena which have been observed. Some of them are very plausible and
satisfactory–to their authors–when applied to a particular class of
facts, but utterly fail when confronted with another class.

Thus, the students of the science of hypnotism are, and since the
days of Mesmer have been, hopelessly divided into schools which wage
war upon each other’s theories, and dispute the correctness of each
other’s observations of facts. Mesmer’s theory of fluidic emanations,
which he termed “animal magnetism,” seemed to account for the facts
which he observed, and is still held to be substantially true by many
votaries of this science. John Bovee Dods’ electrical theory–positive
lungs and negative blood–was sufficiently plausible in its day to
attract many followers, as it afforded a satisfactory explanation of
many phenomena which came under his observation. Braid’s physiological
explanation of certain classes of the phenomena afforded, in his time,
much comfort to those who believe that there is nothing in man which
cannot be weighed in a balance or carved with a scalpel. In our own
day we find the school of the Salpêtrière, which holds that hypnotism
is a disease of the nervous system, that its phenomena are explicable
on physiological principles, that the suggestions of the operator
play but a secondary _rôle_ in their production, and that they can be
produced, or successfully studied, only in diseased persons. On the
other hand, the Nancy school of hypnotists holds that the science can
be studied with profit only in perfectly healthy persons, and from a
purely psychological standpoint, and that suggestion is the all-potent
factor in the production of all hypnotic phenomena. All three of
the last-mentioned schools agree in ignoring the possibility of
producing the higher phenomena of hypnotism, known as clairvoyance and
thought-transference, or mind-reading; whilst the earlier hypnotists
demonstrated both beyond the possibility of a reasonable doubt. Indeed,
a committee of the ablest scientists of the Royal Academy of Medicine
of France, after an investigation extending over a period of six years,
reported that it had demonstrated the existence of such powers in the
human mind.

Another large class of psychological phenomena, which has been
productive of more conflicting theories than any other, and which from
time immemorial has puzzled and appalled mankind, is by a large class
of persons referred to the direct agency of the spirits of the dead.
It would require a volume to catalogue the various theories which have
been advanced to account for this class of phenomena, and when done
it would serve no useful purpose. It is safe to say, however, that
no two individuals, whether believers or unbelievers in the generic
doctrine of spiritism, exactly agree as to the ultimate cause of the
phenomena. The obvious reason is that no two persons have had exactly
the same experience, or have observed exactly the same phenomena. In
the absence of a working hypothesis applicable to all the infinite
variety of facts observed, it follows that each investigator must draw
his own conclusions from the limited field of his own experience. And
when we take into consideration the important _rôle_ which passion
and prejudice ever play in the minds of men when the solution of
an undemonstrable problem is attempted, it is easy to see that a
bewildering hodge-podge of heterogeneous opinions is inevitable.

Another class of phenomena, about which an infinite variety of
opinions prevails, may be mentioned under the general head of mental
therapeutics. Under this generic title may be grouped the invocations
of the gods by the Egyptian priests; the magic formulas of the
disciples of Esculapius; the sympathetic powder of Paracelsus; the
king’s touch for the cure of goitre; the wonderful cures at the tomb of
Deacon Paris and at Lourdes; the miraculous power supposed to reside in
the relics of the saints; the equally miraculous cures of such men as
Greatrakes, of Gassner, and of the Abbot Prince of Hohenlohe; and the
no less wonderful healing power displayed by the modern systems known
as mind cure, faith cure, Christian science, animal magnetism, and
suggestive therapeutics.

One fact, pregnant with importance, pertains to all these systems;
and that is that marvellous cures are constantly effected through
their agencies. To the casual observer it would seem to be almost
self-evident that, underlying all, there must be some one principle
which, once understood, would show them to be identical as to cause and
mode of operation. Yet we find as many conflicting theories as there
are systems, and as many private opinions as there are individuals who
accept the facts. Some of the hypotheses gravely put forth in books are
so bizarre as to excite only the pity or the ridicule of the judicious.
One notable example is found in that system, the basic theory of which
is that matter has no existence, that nothing is real but mind, and
that, consequently, disease and pain, suffering and death, are mere
hallucinations of morbid intellects. Other theories there are, which,
if not equally absurd, are probably equally remote from the truth; and
each treats the persons as well as the opinions of the others with
that virulent contumely which is the ever-present resort of him who
would force upon his neighbor the acceptance of his own undemonstrable
article of faith. Nevertheless, as before remarked, the fact remains
that each of these systems effects some most wonderful results in the
way of curing certain diseases.

What is true of the phenomena embraced under the general head of
mental therapeutics is also true of the whole range of psychological
phenomena; namely, the want of a working hypothesis which shall apply
to all the facts that have been observed and authenticated.

No successful attempt has heretofore been made to supply this want;
nor has success been possible until within a very recent period,
for the simple reason that previous to the discovery of certain
facts in psychological science, the scientific world was without the
necessary data from which a correct hypothesis could be formulated.
The researches of Professor Liébault in the domain of hypnotism,
seconded by those of his pupil, Professor Bernheim, have resulted
in discoveries which throw a flood of light upon the whole field of
psychological investigation. Their field of observation being confined
to hypnotism, and chiefly to its employment as a therapeutic agent, it
is not probable that either of those eminent scientists realized the
transcendent importance of their principal discovery, or perceived that
it is applicable to psychological phenomena outside the domain of their
special studies. The discovery is this: _that hypnotic subjects are
constantly amenable to the power of suggestion; that suggestion is the
all-potent factor in the production of all hypnotic phenomena_. This
proposition has been demonstrated to be true beyond the possibility
of a reasonable doubt. In subsequent chapters of this book it will
be shown that this fact supplies the missing link in the chain of
propositions necessary for a complete working hypothesis for the
subject under consideration.

The general propositions applicable to all phases of psychological
phenomena are here only briefly stated, leaving the minor, or
subsidiary, propositions necessary for the elucidation of particular
classes and sub-classes of phenomena to be stated under their
appropriate heads.

The first proposition relates to the dual character of man’s mental
organization. That is to say, man has, or appears to have, two minds,
each endowed with separate and distinct attributes and powers; each
capable, under certain conditions, of independent action. It should
be clearly understood at the outset that for the purpose of arriving
at a correct conclusion it is a matter of indifference whether we
consider that man is endowed with two distinct minds, or that his one
mind possesses certain attributes and powers under some conditions,
and certain other attributes and powers under other conditions. It
is sufficient to know that everything happens just as though he were
endowed with a dual mental organization.

Under the rules of correct reasoning, therefore, I have a right to
assume that MAN HAS TWO MINDS; and the assumption is so stated, in
its broadest terms, as the first proposition of my hypothesis. For
convenience I shall designate the one as the _objective_ mind, and
the other as the _subjective_ mind. These terms will be more fully
explained at the proper time.

The second proposition is, that THE SUBJECTIVE MIND IS CONSTANTLY

The third, or subsidiary, proposition is, that THE SUBJECTIVE MIND IS