Imagine for a moment that we had no eyes: human beings – if we’d be still be human beings – had only four major senses. If this were the case, would we be able to imagine the sense of sight? I think the answer to this is emphatically negative. Imagine humanity crawling around the globe, ever employed and directed by our sense of touch and sound; imagine what we wouldn’t know about the world today, in terms of astronomy, physics, etc. Could we ever extrapolate knowledge about the planets? Even the things we encountered would be encountered in a markedly different fashion. For example, a sunrise would probably not have the same effect. While the warmth of the sun’s rising would be pleasant, the beauty and magnificence of the rising star, recognized through vision, would be lost. In this line of thinking, let me not forget or overlook the positives of such a position. Perhaps without our sense of sight, we would recognize the beauty of things in a different way, a way lost to a species that operates primarily through its ocular powers. However, I think the point remains: There would be much missing, or at least diminished, in our study if we functioned with only four senses.
This being said, is there perhaps a sixth sense? I’m not, of course, referring to the normal use of the term sixth sense, as in some sort of special mental power of recognition. That aside, could we even imagine what this sixth sense might be, or how it might sense – or what it might let us “see” new things, or the same things in a new way? Just as the four-sensing species could not imagine the sense of sight, we cannot imagine a sixth sense. However, is it silly of me to imagine that a sixth sense is a possibility? Or perhaps a multitude of other senses? Or an infinite amount? If we find a four-sensing species silly to argue against our protestations that there really does exist a fifth sense, aren’t our protestations the same?
In line with the earlier logic, if there does exist a sixth sense – or a 1,000; or an infinite – isn’t there much missing in our recognition of reality? Isn’t there the distinct possibility that there exists reality that we cannot grasp through our five senses? I’m not talking about psychic reality, or invisible monkeys floating in dark matter; no, I’m simply talking about physical matter that needs a different sense to be established. Just as much of our knowledge, if not all, of the planets comes from using our sense of sight, and so this knowledge would be completely absent if we didn’t have this ocular sense, couldn’t there be other matter out there, analogous to our planet-knowledge, that needs a sixth sense? It doesn’t have to be in space; it could be right around us.
This topic is related to the topic of a fourth dimension. (I’m not talking about time as the fourth dimension, since time is part of the third.) Imagine being a two-dimensional creature – or, at the very least, you can only sense in two dimensions. Imagine a picture of person on a table in front of you. If you were able to talk to this person and tell them there was a third dimension, that of volume, they may ask for you to point to it. They understand the difference between two and three dimensions, but they can point to that extra, third dimension. The two-dimensional figure could point north, south, east, and west on the painting, but they necessarily can’t point outside of it, what I might imagine would look like “up” to someone sitting at the table upon which the painting it. The point I’m driving at, amidst my confusing visual, is that a two-dimensional person could not imagine the third dimension; at least he could not imagine what it would look like, or how he would sense within one. Now, might there be a fourth dimension? Using the analogy of the person stuck in a two-dimensional world, aren’t we, in a three-dimensional world, necessarily cut off from imagining the world in these four dimensions?
That being said, why are we prone to claiming the world really only exists in three? Or do physicists not make this assumption? Either way, what is it about reality that we can’t see or understand because of our three-dimensional limitations?