It is a good question. Probing for the answer has led to the discovery of what I call the Philosophical Gap. Apparently there is no answer to this question when applied to perception. Interestingly there are many true answers when the question supersedes perception, namely in the realm of logic/mathematics. One can say with absolute certainty that in Plane Geometry the sum of the angles of a triangle always equals the angle of a line. Of course, before this can be stated, all the terms must be as precisely defined as the comparison they are used to evoke. This is how logic progresses: drawing precisely defined comparisons between precisely defined characteristics. And as the logic of any series of comparisons progresses, each true comparison itself becomes a characteristic. This is relevant to the discussion at hand when one asks "How do you know…?' about any comparison. The question forces one to backtrack the logic used to Prove that there are no weak links all the way back to the beginning of the logical chain.

The beginning of the logical chain? Is there such a thing? This is where the Philosophical Gap comes in. Continuing with the example from above, Plane Geometry can be derived in total from a single Given: the concept of betweenness. But this concept itself has no derivation. If it had one it would not be a Given. Betweenness, it appears, is ad hoc, pulled out of 'thin air' with no explanation. Now, Plane Geometry is absolutely irrefutable within itself (once Given the premise of betweenness). But if it can be shown that in Reality there is no betweenness then it must be said that Plane Geometry cannot apply to Reality. This is independent of any arguments for the usefulness of Plane Geometry. I am not suggesting that, if betweenness is shown to be unreal, that Plane Geometry is impossible to use as an approximate model of what is observed, as long as one remembers that it is intended as an approximation and may not describe what is Really happening. There are no real spheres, but approximating the earth as a sphere can be very useful.

So the Philosophical Gap exists even in pure logic at the point of establishing the Givens, that is, the assumptions on which future logical chains will be based. Maintaining that the notion of betweenness is derived from reality itself usually minimizes the problem. But there is a deeper level. Betweenness is derived as an interpretation of perceptions. And there is no independent way to ascertain for Certain that the way we perceive is congruent with the way things are. The most we can hope is that our perceptions (prior to our interpretations of them) are a genuine reflection of Reality, that our perceptions are themselves real and not hallucination. The recognition that this Gap exists between reality and perception is what led to solipcism. To the question, "Are our perceptions a reflection of reality?" The solipcist will answer, "No." The solipcists error is in thinking that if there is no way of proving our perceptions are trustworthy then it is true that they are not. But not knowing if X is true is not the same as knowing that not-X is true. So the recognition that there is a Gap can and has led many astray, 'throwing out the baby with the bathwater.' One realizes that logic cannot go everywhere, cannot solve all problems, which sometimes leads one to reject logic altogether as a means of solving problems. There is a vicious circle here. Teetering on the brink of rejecting logic, having noticed its limitations, one can begin to allow in irrational conceptions, which can then feed back into the initial reasons for doubting rationality in the first place. If one is not careful, one will arise as a phoenix of irrationality from what one has come to imagine as the waning embers of logic…failing to notice that logic remains alive and the only method for deriving trustworthy reasons for anything. But arriving at illogic through logic is itself a vicious circle because the act of casting doubt on logic using logic casts doubt on any conclusions derived from the logic that one is now commited to portraying as doubtful.

However, if one's intent is to establish the efficacy of perception then one cannot appeal to perceptions without begging the original question of whether perceptions are efficacious in the first place. But what else have we to go on besides our perceptions? Or in the solipcist spirit, what else have I to go on besides my perceptions, including my perceptions of others having perceptions?

Nothing, in reality. But logic supersedes reality. I most certainly do not wish to endorse gross dualism. Certainly our minds, as functions of our brains, are within reality, but they do not function at the unknown (perhaps even infinite) complexity level of reality in which our minds reside. Our minds simplify, idealize, and model natural phenomena in order that we may usefully interact with them. Logic itself was born out of the functions of simplifying, idealizing, and modeling…an excellent example of functions evolved for certain purposes being turned to others…to the point at which we can now confidently say that we have an impregnable method of separating the possible from the impossible.

All this, and yet the Philosophical Gap remains because exactly how and where logic and the phenomenal world intersect is unclear. The world is a certain way but it is not logically necessary that it be this way, except within the far-reaching yet very strict possibilities as elucidated by logic. There are many possibilities in our world that are not actual, yet nothing impossible is allowed.

© K Michau 2005