Читать книгу Applied Psychology for Nurses - Mary F. Porter - Страница 26

I am passing the open door of a bake-shop, and a pervading odor fills the air. I think “hot rolls,” because my organ of smell—the nose—has received a stimulus which it transmits along my olfactory nerves to the brain; and there the odor is given a name—“hot rolls.” The recognition of the stimulus as an odor and of that odor as “hot rolls” is consciousness in the form of thinking. But the odor arouses desire to eat—hunger; and this is consciousness in the form of feeling. The something which makes me walk into the shop and buy the rolls is consciousness in the form of willing. The sensory appeal from the outside world gained admission through the sense of smell; this transmitted the message, and consciousness recognized the stimulus, which immediately appealed to my hunger and incited action to satisfy that hunger.

The ear of the operator in the telegraph office, again, might illustrate consciousness. It must be able to interpret mere clickings into terms of sense. To the operator the sounds say words, and the words are the expression of the object at the other end of the wire. The brain is the receiving operator for all the senses, which bring their messages in code, and which it interprets first as sound, vision, taste, touch, feel, smell, temperature; then more accurately as words, trees, sweet, soft, round, acrid, hot.

The mind can know nothing except as the stimulus is transmitted by sense-channels over the nerves of sense, and received by a conscious brain. A baby born without sight, hearing, taste, smell, or touch would remain a mere bit of clay. He could have no awareness. But so long as any one sense channel remains open the mind may acquire some knowledge.

Suppose I am paralyzed, blind, and deaf, and you put a tennis-ball into my hand. I cannot tell you what it is, not even what it is like. It means nothing whatever to me, for the sense channels of touch, sight, and hearing, through which alone it could be impressed upon my brain, are gone. Suppose I am blind and deaf, but have my sense of touch intact; that I never saw or touched or heard of a tennis-ball before, but I know “apple” and “orange.” I can judge that the object is round, that it is about the size of a small orange or apple. It is very light, and has a feel of cloth. I know it to be something new in my experience. You tell me in the language of touch that it is “tennis-ball”; and thereafter I recognize it by its combination of size, feel, and weight, and can soon name it as quickly as you, who see it.

Suppose I am blind and my hands are paralyzed, but I have my hearing. You tell me this is a tennis-ball, and if I have known “tennis-ball” in the past, I can describe it to you. It has been impressed upon my brain through my sense of hearing; and memory immediately supplies the qualities that go with “tennis-ball.”

But if none of the senses has ever developed, my brain can receive no impression whatever; it cannot have even the stimulus of memory. Hence conscious mind cannot be, except as some sense-channel or channels have been opened to carry thought material to the brain. So far as we know today, in this world, mind is absolutely dependent upon the sense organs and the brain—upon matter—for existence.