But there is another view of the subject. I hold that the bodily senses can only perceive material things; and the spirit spiritual things; and hence, that, admitting the actual presence of disembodied spirits, neither could we perceive them, nor they us, as material bodies. They might, indeed, perceive the souls within us, but could only be cognizant of our actions as those of pure spirit; while we, blinded by the impenetrable screen of the body, would be debarred of even this recognition.
For through only three of the bodily senses--sight, hearing, and feeling--have the boldest of so-called spiritualists dared to attempt the proof of their doctrine. To begin with the latter, the essential quality of the sense of feeling is _resistance_, without which there can be no perception. And what is resistance? In one class of cases it is simply the _vis inertiæ_ of matter: in the other and only remaining one, the opposition of some material matter to the force of gravity. Even the perception of the lightest zephyr depends upon the resistance of the atmosphere. Does spirit possess this quality of resistance? The argument on this head is closed the moment the distinction is made between material things and spiritual.
If the wave theory of light and sound be correct--and it is so generally accepted that few writers dare risk their reputations in the defence of any other--the senses of sight and hearing come, for the purposes of this argument, in the same category. Nothing can affect the ear which is not capable of producing vibration in the atmosphere, which may be considered, in comparison with pure spirit, a material substance. Here again the argument is clinched by the mere distinction between matter and spirit, the one being the very antipodes of and incapable of acting upon the other.
Natural science tells us that the white light of the sun is composed of the seven colors of the spectrum in combination, which colors may be readily separated by the refraction of the prism. All objects possess, in a greater or less degree, the power of decomposing light and absorbing colors. Now a ray of sunlight falling upon any given object is in a measure decomposed, a portion of its integral colors is absorbed, and the remainder or complementary colors thrown off--reflected upon the eye, producing by their combination what we call the color of the object. Thus, a ray thrown upon a pure white object is absorbed not at all, but wholly reflected as it came, and the consequence is the proper combination upon the retina of all the colors, producing--a white object. On the contrary, a ray falling upon what we call a _black_ object, is wholly absorbed, and the consequence is a total absence of light, or blackness. So a red object absorbs all the orange, yellow, green, blue, indigo, and violet of the sunlight, reflecting upon the eye only the red, which is perceived as the color of the object. And so on through all the combinations of the spectrum. Only material substances can either absorb or reflect: therefore is spirit again excluded; for how can it act upon the eye save through those agencies with reference to which the eye itself was constructed, and which, as we have shown, it cannot possibly affect? To sum up the whole argument in a single sentence, the physical senses are dependent, for their perceptions, entirely upon the action of matter, and hence spirit, which is not matter, can in no way affect them.