is loss of consciousness, and the only lesion discovered is softening of
the _corpora striata_; then the following:

"Assuming now that it were proved that the power which creates
consciousness has some definite seat, and that it is a summation of
energies physiologically varying in sleep and waking, which may be
directed to any part of our store of experiences for purposes of
illumination, what portion of the brain is so constructed as to be
in apparently intimate connection with every other? The _corpora
striata_!... There is no portion of the brain we know so little
of.... Here we have a portion of the brain which must be of
enormous significance, otherwise it would not be always present,
from the fish up to man."

It will be seen that Dr. Peterson is here opposed to the doctrine
maintained by both Lotze[5] and MacDougall,[6] who both maintained that:
"There are a number of separate points in the brain which form so many
'seats' of the soul. Each of these would be of equal value with the
rest; at each of them the soul would be present with equal
completeness." But whether there be one or several "seats" of
consciousness, it is obvious that there must be contact of _some_ sort,
at one or several points (granting the correctness of the theory that
spirit acts upon matter at all), and the question is: _How_ may this
action be supposed to take place?

In discussing this question in a former book[7] I said:

"It is more than probable, it seems to me, that there exists some
sort of etheric medium between mind and even organic nervous
tissue, upon which the mind must act first of all. Thus, we should
have the chain of connection: mind, vital or etheric medium,
nervous tissue, muscle, bone. So mind acts upon matter; and it will
be seen that there is an increasing density of structure, and that
just in proportion to this density is mind incapable of affecting
matter directly. We must, it seems to me, always postulate some
sort of etheric medium through which mind acts, in order to affect
and move matter--organic or inorganic. And without this vital
intermediary there can be no action, and consequently no
manifestation."

Now, it would appear rational to suppose that some action of this sort
takes place when mind acts upon, or influences, matter. Air is
invisible, and practically imperceptible to our senses--_wh