Relation Of Mind And Body
We have found that mind is entirely dependent upon the bodily organs for
its existence. Is the body in the same way dependent upon the mind? Can
the mind die and the body go on?
Given a perfect body with unblocked sense channels, and put the mind to
sleep, paralyze the central nervous system with alcohol in sufficient
quantity so that the undamaged peripheral nervous system--the
senses--can obtain no response or recognition from it, and that perfect
body is as useless for the time as if dead. But here comes proof of the
remarkable hold of the body on life. The unconscious mind takes up the
burden of directing the sympathetic nerves to stimulate the muscles of
breathing. The unconscious sees to the beating of the heart. It directs
the contraction of the blood-carrying vessels. It maintains certain
vital processes of secretion. Thus automatically life goes on; the body
still reacts to a limited field of stimuli, and consciousness recognizes
it not. But when the unconscious mind ceases to function, then, indeed,
does the body die. Yet the conscious mind may "die" and the body live
on, so long as the unconscious continues its activity.
It is possible for the human body to live for years, utterly paralyzed,
with many of the senses gone, with no consciousness of being--if cared
for by other persons--a merely vegetable existence. The current of power
is broken; but the spark is still glowing, though utterly useless
because connected with nothing. And it may continue to glow for some
time while properly stimulated from outside sources.
We might liken the mind to the boiler in which steam is generated, and
the body to the engine which the steam runs. If the boiler bursts, the
engine stops; but it may not be otherwise damaged. It simply cannot
carry out its main function of motion any longer. The fires under the
boiler are still burning and can be kept burning so long as fuel is
provided, but the connection is broken and the great bulk of iron is a
useless thing in that it can no longer fulfil its purpose.
In just such a way may the mind be paralyzed; but the spark of life,
which has through all the years kindled the now lost mind to action, may
still remain--a useless thing, which would die away if not tended from
without by other bodies whose minds are still intact.
But in the demented mind consciousness still remains, the awareness of
the young child or baby stage of life. The connection between the upper
or conscious brain centers and the body has been tampered with; it no
longer is direct, but breaks off into switch-lines. But the contact
still holds between the lower or unconscious mind and the body; so the
automatic body functions go on, directed as they were in babyhood before
the independent mind assumed control. Hence, when all acute
consciousness is finally gone, the unconscious mind, a perfect
automaton, may still carry out the simplest vegetative activities of
When body is dead, mind, so far as its reactions to the world we know
are concerned, ceases to act. But when the conscious mind is "dead" the
body may yet live as a vegetable lives, with all its distinctively human
functions lost. Motionless, save for the beating of the heart and the
reaction of the lungs to air, the body may still be alive, though the
mind long since has ceased all earthly activity.
So we discover that an organ of mind is an essential, here, to life of
mind, and that mind only can induce this organ to any action above the
vegetative stage. But, on the other hand, we find that life can exist
without conscious mind, even if untended by others, for a limited time.
If the direct nerve connections between the brain and the hand, the
brain and the foot, or the brain and the trunk are cut off, the mind
henceforth realizes nothing of that part except as the sense of sight
reports upon it; for the optic nerves relate the hand and mind, through
this sense, as truly as the motor nerves which carry the mind's message
for motion to the hand, and the sensory nerves which carry back to the
mind the hand's pain. But let the optic nerve be inert, the sensory and
motor connections broken between brain and hand, or foot and trunk, or
brain and trunk, and the hand or foot may be amputated and the mind
never sense the fact; the trunk may be severely injured and the mind be
serenely unconscious. So the brain in man is "the one immediate bodily
condition of the mental operations." Take away all the brain and man's
body is a useless mass of protoplasm.
The brain's varied and intricate nerve connections with all parts of the
body, through nerves branching from the main trunks in the spinal cord,
we shall not discuss, for you know them through your study of anatomy.
For the purpose of our psychology we need consider only two of the main
divisions of the brain--the cerebrum, which includes what we call the
right and left hemispheres, and the cerebellum.
Next: The Cerebrum Or Forebrain
Previous: The Sympathetic Nervous System