of the world. If I had really made such an assertion, it would be an
error which I am perhaps more ready than others to repudiate, as it
will appear in the present work. I am far from blaming the courteous
critics who allege such objections to my theory, and indeed I am
honoured by their notice. I must blame myself for not having, in my
desire to be brief, sufficiently defined my conception.

I hold the psychical manifestation to be not only conditioned by the
organism, to speak scientifically, and to be rendered physiologically
possible by these conditions, but I consider it to be of the same nature
as the other so-called forces of the universe; such, for example, as the
manifestations of light, of electricity, of magnetism, and the like.
When physicists speak of these forces--if the necessities of language
and the brevity of the explanation constrain us to adopt the term
forces, as though they were real substances--they certainly do not
believe, nor wish others to believe, that they are really such. It is
well known that such expressions are used to signify the appearance
under certain circumstances of some special phenomena which group
themselves by their mode and power of manifestation into one generic
conception as a summary of the whole. They always take place, relatively
to these circumstances, in the same mode and with the same power, so
that they may at once be experimentally distinguished from others which
have been grouped together in like manner.

Such manifestations do not imply a real cosmic entity of these forces,
as if they were independent of the matter whence they issue; they are
simply determinate and determinate modes of motions, of actions, and
reactions in the elements of the world. For if magnetism appears to
reveal itself in determinate elements, its modes of manifestation are
peculiar to itself, and its efficacy with respect to other forces is