Our Senses Limited

"We also often overlook the fact that our senses have only a limited range and give us a very incomplete picture even of the physical world around us. This is strikingly illustrated by an examination of the electromagnetic spectrum.

When sunlight is made to pass through a glass prism it is broken up into seven different colors, each one caused by radiations of different wave lengths from the others. At one end of this spectrum or color band is the violet light, with relatively short wave lengths; at the other end is the red light with wave lengths almost twice the length of the violet light; and between these two extremes are the other colors, each with its own intermediate wave length. All of these radiations can be seen by the human eye.

But the electromagnetic spectrum extends far beyond the visible light-spectrum, both on the side of longer and shorter wave lengths. Radiations are known that vary all the way from those with wave lengths just a little too long for the human eye to see, up to those that are many millions of times longer. Likewise radiations are known with wave lengths so short that it requires millions of them to equal the shortest one visible to the human eye. As scientific knowledge increases, the electromagnetic spectrum is extended. For all we know it may extend indefinitely in both directions, and among this almost infinite variety of radiations, the little group that can be seen by the human eye forms but an infinitesimally small part.

Some radiations that cannot be detected by the eye can be perceived by our sense of touch, since they generate heat. If we were absolutely blind we would still be aware of these heat radiations, but would be unable to sense the light with which we might be flooded. If our eyes were normal but we lacked the sense of touch, we would recognize the light, but we would be unaware of the existence of the heat radiations that might be pouring in on us.

Common photographic plates are sensitive to ordinary light, but plates have been made with chemicals that are sensitive to invisible radiant heat. An audience seated in a room from which all light had been excluded was photographed by means of these invisible rays, sometimes called "black light." The audience saw nothing and felt nothing, and could not detect the presence or absence of these rays, but the resulting photograph, which looked to all appearances like an ordinary photo, demonstrated their presence.

X-rays have the ability to penetrate material bodies. Pictures have been taken of objects through a plate of four-inch solid steel. But perhaps this is not so surprising when we are told by our scientists that there is no such thing as "solid matter," but that what appears to us as solid is mostly empty space, and that the atoms in matter are relatively as far apart as are the stars in space. And further, we are told that the atoms themselves are not solid, but consist of various energy charges moving around one another at incredible velocities. Matter then, which to our touch and our sight seems solid, is in reality mostly empty space, and what little "substance" there is in matter is electrical in nature. This is something about which our unaided senses failed to inform us.

Certain rocks, which in daylight appear no different from those found in any field or gravel pit, are sensitive to ultra-violet radiation. If these rocks are placed in a darkroom and subjected to ultra-violet rays, which are also invisible, the rocks, although not hot, seem to glow and become translucent, apparently exposing the interior of the rocks, and this becomes illuminated in different and most beautiful colors. These radiations seem capable of penetrating to the interior of the solid rock and in their passage through the rock produce a change in this or are themselves transformed into radiations that come within the range of human vision. Illuminated by this invisible light these drab-looking rocks display an aspect of unsuspected beauty.

One cannot help speculating on what fairyland of beauty this world might present if our eyes were tuned to see by ultra-violet radiations instead of by ordinary sunlight.

The cat and the owl have eyes with a different range of vision from those of man. They "see in the dark." In other words, their eyes are sensitive to some of the radiations that are invisible to us. Hence, what is darkness to us is light to them. This shows how even eyes of physical matter can be constructed so as to embrace different ranges of visibility.

X-rays and cosmic rays as well as ultra-violet rays can penetrate and pass through solid matter. May there not be eyes constructed that can follow these rays and thus see through physical substance as though it were empty space, just as our eyes can see through air and water?

Scores of telephone messages can be sent over the same wire at the same time without interfering with one another, simply by using different wave lengths in transmitting them. As we talk we are unaware of other conversations mingling with ours, yet in the end they are all separated and reach their destination as though the others did not exist.

The air is constantly filled with radio waves of various lengths and yet we are entirely unaware of their presence until we turn on our radio. As we shift from station to station around the dial, we hear the most diverse programs being broadcast all at once, yet not interfering with one another if the apparatus is properly adjusted.

Ether vibrations of many different wave-lengths can thus interpenetrate each other and co-exist in the same space without interfering with one another and without making any impression on the human senses.

Vibrations in the air reach us as sound waves, but our ears, like our eyes, are limited in their capacity to register these. There are sound waves of too low a pitch and others of too high a pitch for the human ear to record.

Our senses of touch, taste and smell seem relatively less evolved that those of sight and hearing and tell us very little of the world in which we live.

Our senses, on which we depend for contact with the physical world, are like windows through which we can look out and observe the world around us, but they are very small windows, narrow slots, little "periscopes" that only permit us to see a small part of the phenomenal world in which we live. By means of various mechanical and electrical devices we have been able to extend our field of vision considerably. Even with these aids, however, the picture our senses give us is very incomplete. What may lie beyond the reach of these devices is unknown territory to us.

Our present knowledge, nevertheless, is sufficient to demonstrate that there exists an unseen side in nature. It is unseen because of the limitations of our senses and not because it does not exist.

There is nothing in our present knowledge that conflicts with the idea of invisible sides to Nature. For all we know to the contrary, there might very well exist whole worlds or planes of different rates of vibration from our own, in which might exist, live and move other sets of beings, whom we could not cognize, and who might be unaware of our existence.

A denial of the possible existence of invisible planes because they are invisible, has no better basis than the blind man's denial of the light, or a deaf man's denial of sound."

-"Life's Riddle" by Nils A. Anmeus, Ch. 3 'The Unseen Side of Nature'