It is usual to begin all teaching concerning the mind by a general discourse upon "the senses." This is, indeed, the only logical approach to the main subject, for the impressions received by us through the senses—the '' sensations"—have well been called "the raw materials of mental activities." It is well that the Master Mind become acquainted with these "raw materials" which it expects to use.
In popular usage the term "sense" is commonly employed as identical with '' understanding,'' or "reason"; but in psychology the term has a far more restricted meaning. In psychology the term "sense" has the following meaning: "The faculty possessed by conscious creatures whereby they perceive external objects by means of impressions made upon certain organs of the body, or whereby they receive impressions concerning changes in the condition of the body." The term "sensation," in psychology, is defined as: "An impression made upon the mind through the medium of the nervous system, and usually through one of the organs of sense."
The senses are usually regarded as consisting of five general classes, each with its appropriate organism of sensation, as follows:
The Sense of Touch, or Feeling
The sense of Touch, or Feeling, is regarded by psychologists as the elementary sense—the one sense from which the others have evolved, and of which they are, in a way, an evolution. The sense of Touch, or Feeling, operates by means of certain nerves which have their endings in the outer covering or skin of the body, and also in the internal organism of the body. These nerves report to the mind their contact with outside objects; and, in some cases, certain changes of state or condition in the body itself. By means of this sense we are able to become aware of the size, form, shape and delight of material objects; of their degree of hardness, roughness, elasticity, etc.; of their temperature; and of other physical characteristics by which we distinguish one material object from another by means of respective reaction to our sense of Touch or Feeling. By means of this sense we also become aware of changes of state or condition in our bodies, such as thirst, hunger, sexual-feeling, and other "internal sensations."
The mechanism of the sense of Touch, or Feeling, is composed of many different and varied classes of nerve channels. This being so, the sense of Touch, or Feeling, is really a composite sense, manifesting diverse activities, principal among which are those of pressure, temperature, muscular resistance, pain, contact, etc. This diversity of activity is illustrated of the physiology of the senses: "A lesion which may cut off the possibility of feeling pain in a given part of the body, may leave it still susceptible to sensations of heat and cold; or the sensations of touch may be present while the sensation of pain cannot be aroused. From this we see that nerve impulses, giving rise to sensations of touch, of pain, of temperature, of the muscular sense, must pass upwards to the sensorium by different paths, one of which may be cut off while the others remain."
The Sense of Sight
The sense of Sight, regarded by psychologists as an evolution of the elementary sense of Touch or Feeling, is regarded by the best authorities as the highest in the scale of the evolved senses. It manifests through a most complex organism and nerve- arrangement. The sense of Sight operates by means of registering the sensations of the intensity of the light waves, and the color vibrations thereof. The eye does not touch or feel the outside objects in order to "see" them; instead, it "touches" or "feels" the vibrations of the lightwaves coming in contact with the nervous matter of the organ of sight.
A leading text book on the subject of physiology describes the mechanism of the organ of sight as follows: "The optical apparatus may be supposed for the sake of description to consist of several parts. First, of a system of transparent refracting surfaces and media by means of which images of external objects are brought to a focus upon the back of the eye; and, secondly, of a sensitive screen, the retina, which is a specialized termination of the optic nerve, capable of being stimulated by luminous objects, and of sending through the optic nerve such an impression as to produce in the brain visual sensations. To these main parts may be added, thirdly, an apparatus for focusing objects at different distances from the eye, called 'accommodation.' Even this does not complete the description of the whole organ of vision, since both eyes are usually employed in vision; and forthly, an arrangement exists by means of which the eyes may be turned in the same direction by a system of muscles, so that binocular vision is possible. The eye may be compared to a photographic camera, and the transparent media corresponds to the photographic lens. In such a camera images of objects are thrown upon a ground-glass screen at the back of a box, the interior of which is painted black. In the eye, the camera proper is represented by the eyeball with its choroidal pigment, the screen by the retina, and the lens by the refracting media. In the ease of the camera, the screen is enabled to receive clear images of objects at different distances, by an apparatus for focusing. The corresponding contrivance in the eye is the 'accommodation.' The iris, which is capable of allowing more or less light to pass into the eye, corresponds with the different-sized diaphragms used in photographic apparatus." The "retina" of the eye, above mentioned, is a very sensitive membrane of nerve-matter lining the back of the eye, and being connected with the minute ends of the optic nerve; from the retina the impression is conveyed by the nerves to the brain.
The Sense of Taste
The sense of Taste, another evolved sense, manifests by means of certain nerves terminating in tiny cells of the tongue, known as "taste buds"; the latter are stimulated chemically by objects brought in contact with them, the impulse being conveyed to the nerves, and by them transmitted to the brain. Physiologists classify the sensations of taste into five classes, viz., sweet, sour, bitter, salty, and "hot" (as in the case of pepper, etc.).
The Sense of Smell
The sense of Smell, another evolved sense, manifests by means of delicate nerves terminating in the mucus membrane of the nostrils; the latter registering contact with minute particles of material objects entering the nostrils, and also registering differences in the chemical composition of such particles; the message of the nerve ends being transmitted to the brain. The particles of the "smelled" object must have actually entered the nostrils and have come in contact with these nerve ends in order to have been sensed. Mere nearness to the organ of smell is not sufficient—actual contact must be had, or we will smell nothing. We "smell" the rose only because minute particles of its substance are carried into our nostrils. We smell gas because some of its particles enter our nostrils.
The Sense of Hearing
The sense of Hearing, another evolved sense, manifest by means of delicate nerve terminating in the inner part of the ear. The eardrum, or "tympanum," vibrates in response to the air-vibrations or sound-waves reaching it from the outside; these vibrations are intensified, and the auditory nerve-ends take up the impression and pass it on to the brain. Sound-waves are sensed according to their characteristics of pitch, intensity, quality, and harmony, respectively.
The Offices of the Senses
The senses constitute the doors to the outside world, which when opened permit the entrance of messages from that world, but which, closed, bar the entrance of anything from without. Few of us ever stop to think how completely we are dependent upon these doors of the senses for our knowledge, our experience, and our objects of thought. We take it all for granted, and fail to perceive the importance of these senses. Only when one or more of the senses fail us do we begin to realize their importance, and the importance of sensations as a whole. It is only when we stop to think how completely shut in, and shutout, we would be if all of our senses were destroyed, that we begin to realize just how dependent we are upon the senses and sensation for our knowledge, our thoughts, our feelings, and our general mental life and being.
A leading psychologist has said: "Suppose a child of intelligent parents were ushered into the world without a nerve leading from his otherwise perfect brain to any portion of his body; with no optic nerve to transmit the glorious sensations from the eye, no auditory nerve to conduct the vibrations of the mother's voice, no tactile nerves to convey the touch of a hand, no olfactory nerve to rouse the brain with the delicate aroma of the orchards and the wild flowers in spring, no gustatory, thermal, or muscular nerves. Could such a child live, as the years rolled on, the books of Shakespeare and of Milton would be opened in vain before the child's eyes. The wisest men might talk to him with utmost eloquence all to no purpose. Nature could not whisper one of her inspiring truths into his deaf ear, could not light up that dark mind with a picture of the rainbow or of a human face. No matter how perfect might be the child's brain and his inherited capacity for mental activities, his faculties would remain for this life shrouded in Egyptian darkness. Perception could give memory nothing to retain, and thought could not weave her matchless fabrics without materials."
Another psychologist has said: "If it were possible for a human being to come into the world with a brain perfectly prepared to be the instrument of psychical operations, but with all the inlets to sensations closed, we have every reason to believe that the mind would remain dormant like a seed buried in the earth." Another says: "That the powers of the understanding would forever continue dormant were it not for the action of things external to the body, is a proposition now universally admitted by philosophers." Another says: "Apprehension by the senses supplies directly or indirectly the material of all human knowledge, or at least the stimulus necessary to develop every inborn faculty of the mind.'' Another says: "Even the highest ideas are slowly and gradually developed from the accumulation of sense experiences, and their truth is only guaranteed by the possibility of finding concrete examples for them in real existence. Another says: "The activity of the mind is just as much the result of its consciousness of external impressions, by which its faculties are called into play, as the life of the body is dependent upon the appropriation of nutrient materials and the constant influence of external forces." And another: "The senses are the means by which the mind obtains its knowledge of the outside world. Shut out from all direct communication with the outer world, it knows, and can know, nothing of what exists or is passing there, except what comes to it through the senses. Its knowledge of what is external to itself is therefore dependent upon the number, state, and condition of the sensory organs.''
In short: Psychologists hold that if a human being were born without sense organs, no matter how perfect a brain he might have, his life would be little more than that of the plant. He would exist in a dreamlike state, with only the faintest manifestations of consciousness. His consciousness would not be able to react in response to the impact of contact with the outside world, for there would be no such impact. And as consciousness depends almost entirely upon the impact of, or resistance to, outside impressions, his power of consciousness would be practically not called into play. He would perhaps be conscious of his own existence, but would probably never realize the fact fully, for he would have nothing else with which to compare himself, and his self-consciousness would not be aroused by the presence and pressure of the "not self." Such a man would not even have the memories of previous sensations, or experiences, to arouse or to heighten his consciousness or thought—and, consequently, he would have no imagination to use. He would be, to all intents and purposes, a "living corpse."
Helen Kellar had only two doors of sensation closed to her—the sense of Sight and that of Hearing. Touch, Taste, and Smell, however, were left to her; and each was quickened and heightened in order to help as far as possible to perform the work properly belonging to the defective senses. Her sense of Touch, especially, was wonderfully increased and quickened into activity; and through this channel her "self" was finally reached and communicated with by loving friends and teachers. The result in this particular case was almost a miracle—yet only two senses were missing. To get the full realization of the importance of the senses, one had but to think of the mental state of a Helen Kellar deprived from birth of the sense of Touch!
Arising from the above line of thought is the realization, that just as the world of the individual is decreased by each sense subtracted from him, so would his world be increased by each sense that might be added to him. And daring minds consider it not improbable that the human race, in the course of evolution, may eventually develop other and more complex senses. Even as it is, man is able to perceive only a limited number of sound sensations—there are many sounds above and below his scale that he is unable to perceive, but which are registered on instruments. Likewise, there are light waves below and above the human scale of perception, but which are caught by delicate instruments. And, at present, man is unable to "sense" electrical waves, or magnetic waves—though, theoretically, it is possible for him to sense these vibrations as well as light waves, or sound waves, the difference between these various "waves" being simply that of the rate of vibration. Imagine what a new world would be opened to man if he could sense the waves of electricity. In that case he could "see" things as far off as these waves could carry, and even though solid objects intervened—just as now, by means of an artificial screen, he is able to see through solid objects by means of the X-Ray. This is by no means a fanciful idea.
A leading authority has said: "If a new sense or two were added to the present normal number, in man, that which is now the phenomenal world for all of us might, for all that we know, burst into something amazingly different and wider, in consequence of the additional revelation of these new senses." And another says: "It is not at all improbable that there are properties of matter of which none of our senses take immediate cognizance, and which other beings might be able to see in the same manner that we are sensible to light, sound, etc." Another says: ""We know that our sensory nerves are capable of transmitting to the brain only a part of the phenomena of the universe. Our senses give us only a section of the world's phenomena. Our senses usher only certain phenomena into the presence of our minds. If we had three or four new senses added, this might appear like a new world to us; we might become conscious of a vast number of phenomena, which at present never have any effect upon our nervous organisms. It is possible to imagine a race of beings whose senses do not resemble ours, inhabiting other worlds.''
A fanciful illustration of the part played by the senses in our mental world is offered by a writer who says: "The late Professor James once suggested as a useful exercise for young students a consideration of the changes which would be worked in our ordinary world if the various branches of our receiving instruments happened to exchange duties; if, for instance, we heard all colors, and saw all sounds. All this is less mad than it seems. Music is but an interpretation of certain vibrations undertaken by the ear, and color but an interpretation of other vibrations undertaken by the eye. Were such an alteration of our senses to take place, the world would still be sending us the same messages, but we should be interpreting them differently. Beauty would still be ours, though speaking another tongue. The birds' song would then strike our retina as a pageant of color: we should see all the magical tones of the wind, hear as a great fugue the repeated and harmonized greens of the forest, the cadences of stormy skies. Did we realize how slight an adjustment of our own organs is needed to initiate us into such a world, we should perhaps be less contemptuous of those mystics who tell us that in moments of transcendental conscious they 'heard flowers that sounded, and saw notes that shone,' or that they have experienced rare moments of consciousness in which the senses were fused into a single and ineffable act of perception, in which color and sound were known as aspects of the same thing."
As has been said, at the last all of the five senses are regarded by physiologists and psychologists as but different aspects or phases of the one elemental and basic sense, the Sense of Feeling. This is more fully realized when we consider that all impressions made upon the organs of sense arise from the motion of material particles, from the outside world, coming in contact with sensitive portions of the nervous system of the individual, the report of the contact being then transmitted to his brain. As an authority has said: "The only way the external world affects the nervous system is by means motion. Light is motion; sound is motion; heat is motion; touch is motion; taste and smell are motion. The world is known to sense simply by virtue of, and in relation to, the motion of its particles. Those motions are appreciated and continued by the nervous system, and by it brought at length to the mind's perception. The last material action we can trace in every process of sensation previous to its entering the abode of consciousness is motion."
And so, at the last, we are conscious of these different forms of motion of things of the outside world by some form of the sense of Feeling. Sight is but the feeling of the impact of the light vibrations; Sound, but the feeling of the impact of the sound vibrations; Taste, but the feeling of the vibrations of chemical action of the particles of material substances brought in contact with the taste-nerves; Smell, but the impact of the particles of material substance brought in contact with the nerves of smell; Touch, but the feeling of the contact with outside physical objects; and Internal Feelings but the feeling of certain states of conditions of the internal organs or parts of the body of the individual. And so, we see that the various sensations are all but forms or phases of the "feeling" arising from the contact with certain sensitive nerve- ends with outside things, and the transmission of such report to the brain.
When these reports to the brain are made, the sense impression becomes a full "sensation." An authority says: "A sensation is a state of consciousness resulting from nerve action. When a stimulation of a sensory nerve is transmitted to the brain, so as to affect consciousness, the result is a sensation. No one can tell us why nerve action affects consciousness, but such is the fact." And here we come into the presence of the great mystery of consciousness. Consciousness is different from anything else in the world of our knowledge or experience. It can be known only to itself and by itself, but even itself does not know "just what" it is, or how it is. As Huxley, the eminent scientist once said: "How it is that anything so remarkable as a state of consciousness comes about by the result of irritating nervous tissue, is just as unaccountable as the presence of the genii when Aladdin rubbed his lamp." We shall in this book make no attempt to tell "just what" consciousness is, but shall content ourselves with telling our readers "just how" it works, and how to use it efficiently and to the best advantage.
We have here seen the mechanism of the senses whereby the Ego is established in communication with the outside world. Dwelling alone in calm solitude, the Ego is constantly receiving the messages from without its dwelling place, as well as from the different rooms of its own place of abode. Telegraph and telephone lines run into that central office, from all directions—telescopes and other optical appliances are trained to all points—heat-registering, light-registering, sound-registering, and motion- registering instruments are at hand and in constant use. All these instruments have been furnished by Nature for the use of the Ego—or, as some prefer to state it, the Ego has fashioned these instruments to meet its requirements. And, always remember this: It is the Ego who feels, the Ego who smells, the Ego who tastes, the Ego who hears, the Ego who sees—and not the sense organs which have been described in this chapter. And if other channels of sensation are opened up to the Ego, or by the Ego, in the future evolution of the race, it will then be the Ego who perceives through them. Back of all sensations is the Ego—the Subject to which all the rest is objective.
The Culture of the Senses
The senses may be cultivated in two general ways, as follows: (1) By maintaining the sense organs in a state of perfect health and normal functioning; (2) by employing each sense by means of the voluntary attention, according to the universal "Law of Use" which operates so as to develop and perfect the physical organs and parts, and the mental faculties, in response to the demands made upon them by Use and Active Employment. The first of the above mentioned methods are outside of the field and scope of this book, and the student is referred to works along the general lines of physiology and physical well-being for detailed information on this score. The second of the above mentioned methods will be considered in detail as we proceed in this book to a consideration of the subjects of Perception and Attention, respectively. Here is the thing in a nutshell: The senses may be cultivated and rendered more efficient by (a) giving the sense-organism the proper physical care and attention, and by (b) employing the senses intelligently and toward definite ends under the direction of the will. And the latter is a task of the Master Mind.