INWARDNESS OF ENVIRONMENT
[Sidenote: _Factors of Success or Failure_]
The aspect of the sense-perceptive process that deals with the
relation of mind to environment is of greatest practical value.
Look at this subject for a moment and you will see that the world
in which you live and work is a world of your own making. All the
factors of success or failure are factors of your own choosing and
creation.
If there is anything in the world you feel sure of, it is that you
can depend upon the "evidence of your own senses," eyes, ears,
nose, etc. You rest serene in the conviction that your senses
picture the world to you exactly as it is. It is a common saying
that "Seeing is believing."
[Sidenote: _Should Seeing Be Believing?_]
Yet how can you be sure that any object in the external world is
actually what your sense-perceptions report it to be?
You have learned that a countless number of physical agencies must
intervene before your mind can receive an impression or message
through any of the senses.
Under these conditions you cannot be sure that your impression of
a green lamp-shade, for instance, comes through the same sort of
etheric and cellular activities that convey a picture of the same
lamp-shade to the brain of another. If the physical agencies through
which your sense-impressions of the lamp-shade filter are not
identical with the agencies through which they pass to the other
person's brain, then your mental picture and his mental picture
cannot be the same. You can never be sure that what both you and
another may describe as green may not create an entirely different
impression in your mind from the impression it creates in his.
Other facts add to your uncertainty. Thus, _the same stimulus_
acting on _different organs_ of sense will produce _different
sensations_. A blow upon the eye will cause you to "see stars"; a
similar _blow_ upon the ear will cause you to _hear_ an explosive
sound. In other words, the vibratory effect of a _touch_ on eye
or ear is the same as that of _light_ or _sound_ vibrations.
[Sidenote: _Hearing the Lightning_]
The notion you may form of any object in the outer world depends
solely upon what part of your brain happens to be connected with
that particular nerve-end that receives an impression from the
object.
You _see_ the sun without being able to _hear_ it because the only
nerve-ends tuned to vibrate in harmony with the ether-waves set in
action by the sun are nerve-ends that are connected with the brain
center devoted to sight. "If," says Professor James, "we could
splice the outer extremities of our optic nerves to our ears,
and those of our auditory nerves to our eyes, we should hear the
lightning and see the thunder, see the symphony and hear the
conductor's movements."
[Sidenote: _Importance of the Mental Make-Up_]
In other words, the kind of impressions we receive from the world
about us, the sort of mental pictures we form concerning it, in fact
the character of the outer world, the nature of the environment in
which our lives are cast--_all these things depend for each one of
us simply upon how he happens to be put together, simply upon his
individual mental make-up_.
There is another way of examining into the intervening agencies that
influence our mental conception of the material world about us.
[Sidenote: _Unreality of "The Real"_]
Look at the table or any other familiar object in the room in which
you are sitting. Has it ever occurred to you that this object may
have no existence apart from your mental impression of it? Have you
ever realized that no object ever has been or ever could be known
to exist unless there was an individual mind present to note its
existence?
If you have never given much thought to questions of this kind,
you will be tempted to answer boldly that the table is obviously a
reality, that you have a direct intuitive knowledge of it, and that
you can at once assure yourself of its existence by looking at it
or touching it. You will conceive your perception of the table as
a sort of projection of your mind comfortably enfolding the table
within itself.
[Sidenote: _"Things" and their Mental Duplicates_]
But perception is obviously only a state of mind. Can it, then, go
outside of the mind to meet the table or even "hover in midair like
a bridge between the two"? If you perceive the table, must not your
perception of it exist wholly within your own mind? If, then, the
table has any existence outside of and apart from your perception
of it, then the table and your mental image of the table are two
separate and distinct things.
In other words, you are on the horns of a dilemma. If you insist
that the table exists _outside_ of your mind, you must admit that
your knowledge of it is not direct, immediate and intuitive, but
_indirect_ and representative, because of intervening physical
agencies, and that the only thing directly known is the _mental
impression_ of the table. On the other hand, if you insist that your
knowledge of the table is direct, immediate and intuitive you must
admit that the table is only a mental image, a mental reality, if it
is any sort of reality at all, and that it has no existence outside
of the mind.
[Sidenote: _Effect of Closing One's Eyes_]
You may easily convince yourself that the table you directly
perceive can be nothing other than a mental picture. How? Simply
close your eyes. It has now ceased to exist. What has ceased to
exist? The external table of wood and glue and bolts? By no means.
Simply its mental duplicate. And by alternately opening and closing
your eyes, you can successively create and destroy this mental
duplicate.
[Sidenote: _If Matter Were Annihilated_]
Clearly, then, the table of which you are directly and immediately
conscious when your eyes are open is always this _mental duplicate_,
this aggregate of color, form, size and touch _impressions_; while
the real table, the physical table, may be something other than the
one of which you are directly aware. This other thing, this physical
table, whatever it is, can never be directly known, if indeed it has
any existence, a fact that many distinguished philosophers have had
the courage to deny.
Imagine, then, for a moment that everything except mind should
suddenly cease to exist, but that your sense-perceptions--that is
to say, your perception of sensory impressions--were to continue to
follow one another as before. Would not the physical world be for
you just exactly what it is today, and would you not have the same
reasons for believing in its existence that you now have?
[Sidenote: _If Mind Were Annihilated_]
And, conversely, if the world of matter were to go on, but all
mental images, all perception of sense-impressions, were to come
to an end, would not all matter be annihilated for you when your
perceptions ceased?
_It is obvious that the world is not the same for all of us; but
that it is for each one of us simply the world of his individual
perceptions._
[Sidenote: _As Many Worlds as Minds_]
The whole subject of sense-impressions, sensation and perception
may, therefore, be looked at from the standpoint of the mind as an
active influence, as well as from the standpoint of outside objects
as the exciting causes of sense-impressions.