This wonder of an elephant Is very like a spear.' "The third approached the animal, The squirming trunk within his hands, 'I see,' quoth he, the elephant Is very like a snake.' "The fourth reached out his And felt above the knee. eager hand 'What most this wondrous beast is like Is mighty plain,' quoth he; 'Tis clear enough the elephant "The fifth, who chanced to touch the ear, Said: E'en the blindest man Can tell what this resembles most: Deny the fact who can? This marvel of an elephant "The sixth no sooner had begun About the beast to grope, "And so these men of Indostan Disputed loud and long DOCTRINE OF RELATIVITY "MORAL "So oft in theologic wars The disputants, I ween, Of what each other mean, NOUMENON AND PHENOMENON 39 John Fiske expresses this in his "Cosmic Philosophy," thus: "The doctrine of relativity affirms the existence of an unknowable reality of which all phenomena whatever are the knowable manifestations." To this unknowable is given the name of noumenon or the real thing, in distinction from phenomenon, which is the increment man knows of the real thing. The story is told that when a missionary visited some Indians and explained to them the Christian theology, with considerable emphasis on the final state of the unredeemed, the chief showed considerable skepticism. With an arrow he drew a small circle in the sand, then a larger circle enclosing the first. Pointing to the inner circle, he said: "This is what Indian know." Pointing to the outer circle: "This is what white man know." Then sweeping the arrow outside the periphery of the larger circle: "Out here Indian know just as much as white man." As a further illustration may be mentioned the old story of the doctor who denied the existence of the soul, because his dissecting knife failed to reveal anything of this nature. He would believe nothing that he could not see. Then the minister asks him if he can see a pain, and if not why he believes in pain. Of course he replies that he feels the pain, whereupon the clergyman replies that he knows of spiritual matters by other senses, which are (perhaps) in the doctor undeveloped. The mental attitude which is undaunted by the restraints of the evidence of the senses is undoubtedly dangerous to the attainment of truth. To claim that one possesses transcendental royal roads to knowledge is intolerable to the scientific mind, yet a recognition of the limitations of our knowledge of the simplest fact must have a salutary effect upon our egotistic tendencies. This relativity is especially apparent when we consider the special senses. For example, the membrana tympana is made to vibrate in unison with waves of air emanating from some sonorous body, but those waves must reach a velocity of sixteen per second before they are audible to the human ear. We have abundant evidence that the solar spectrum extends far beyond the visible spectrum. The wonderful development of the sense of smell in the dog simply baffles our comprehension. "Thus we learn," as Spencer says in his "First Principles," "the greatness and the littleness of the human intellect its power in dealing with all that comes within the range of experience; its EVOLUTION OF THE SENSES 41 impotence in dealing with all that transcends experience." THE TACTILE SENSE As the more delicate senses have evolved from simple sensitiveness to contact or the touch sense, it may be interesting to note that a simple refinement of this contact sense is evident thruout. Taste requires that the article brought in contact with the sense organ shall be soluble. In smell, which is closely allied, the contact of finely divided particles of matter is effected by their floating in the air. The matter may be as finely divided as the gaseous state. Hearing requires only the contact of air itself in waves, but still contact is here. The hammer-like form of the organ of Corti is very suggestive of this essential element contact. The end organs of the optic nerve are the rods and cones of the retina. The contact here is the extreme refinement of touch. The ether wave initiated by the luminous body is condensed by the lenticular system of the eye into an irritant point, the focus, which touches the retina. This principle of contact and the fact that the special senses are merely a refinement of the same are of immense advantage in explaining some of our sight perceptions. The other general principle which should be recognized is the outward reference of sensation. The common experience of striking the ulnar nerve at the elbow and feeling the sensation at the tip of the little finger illustrates a general principle which applies to all the senses. This outward reference may be made to extend beyond the finger. Tap the floor with a somewhat flexible cane with the eyes closed and we feel the contact at the end of the cane. Perhaps we have all had the unpleasant experience of "seeing stars" from a blow on the eye. This is because an irritation of the optic nerve gives a sensation of light which is referred outward into space. This is also proof of the specialization of the optic nerve. Moreover, the testimony of those from whom it has been necessary to remove the eye without an anesthetic is that, when the optic nerve is divided, not pain but a flash of light is the resulting sensation. This outward reference of the sense of hearing is one means of estimating direction. Notice the involuntary turning of the head so as to put the auricle at right angles to the sound wave. This is in obedience of the general law that all irritations reaching these special senses are referred back to their source. SIGHT The refinement of touch and outward reference reaches its highest development in sight. Primitive eyes and ears bear a strong resemblance to each other. Later the eye has for its prototype the pigment spot. This suggests that sight developed first as an actinic susceptibility, the pigment spot absorbed the heat of the luminous body, and thus be |