[This piece originally appeared in The Thought in 1993 and is a response to Julian Tebye's "Response to Daniel C. Ust", which appeared in The Thought, 4/93.]
Julian Tebye replied ("Response to Daniel C. Ust", The Thought, 4/93, hereafter RTU) to both my review of David Kelley's The Evidence of the Senses ("Perception and Realism", TT, 10/92, hereafter PAR) and "Ust Contra Tebye" (TT, 1/93, hereafter UCT). I'm glad he read Kelley's book and replied to me, but there are some issues he didn't address or address properly.
My refutation of skepticism was aimed at the "wider sense" -- "doubting everything, including existence and knowledge." I wrote "Total skepticism... is self-contradictory. It rests on the claim that knowledge is not possible.. . if knowledge is impossible, then so is the claim "knowledge is impossible" ... Thus skepticism refutes itself." (UCT) Yet Tebye believes this refutes Gorgias only and not Pyrrho, who "denied the possibility of knowledge altogether." (RTU) From the looks of it, Gorgias was the bigger skeptic. He denied existence, knowledge and the possibility of communicating knowledge. My argument is aimed at the denial of knowledge but it analogically applies to any denial of existence. (If you claim "nothing exists", then you must also deny that your claim "nothing exists" exists, ergo, your claim is a contradiction.)
He misses Kelley's point about skeptical arguments from dreams, illusions, and sensory relativity. First, Kelley maintains the senses and consciousness have an identity, i.e., they exist and function in certain ways and not others. They are limited by their natures. That my eyes see only a small portion of the spectrum and work under only certain conditions is no ground for the skeptic to stand on. How else would eyes work? Would they have to see all forms of radiation under all conditions without any variations? I'm not sure how Tebye misses this, since he wrote "we can perceive only that for which we have perceptors." He misses a point he grasps elsewhere!
Second, from where do the skeptics get their knowledge of perception and its limits? From perception, of course! For example, to know that a white shirt looks yellow under a yellow light, one has to perceive that the shirt is white under a white light and then see it under yellow light. How can one claim knowledge that our perceptual apparatus might be faulty except by perceiving such faultiness?
Further on, Tebye wonders "how can we ever be certain that what we perceive is all that is "there"?" At no point does Kelley make the claim that the only things that exist are those we perceive. In fact, this is the claim of some idealists, e.g., Berkeley. Of course, historically, we have come across knowledge of things we can't perceive directly, such as x-rays, ultrasound, microscopic life and magnetic fields. But perception is our only contact with reality. In order to learn of a thing that exists we must either perceive it or perceive its effects on those things we can perceive.
Quoting Tebye misquoting me: "When you say that "(reality) is not a form of skepticism" and "not a halfway house between optimism and pessimism" ...well, denotatively, I must agree." (RTU, p13) My original stated, "Also, realism, in the sense of conformity to reality, is not a halfway house between optimism and pessimism. Nor is it a form of skepticism." In both sentences I'm talking about "realism", not "reality"! There's a difference between the two. "Realism" is a philosophical position (a set of ideas). "Reality" is "what is, nothing more, nothing less." (UCT) Compare this with the difference between "Marx" and "Marxism". This kind of sloppiness has led to much confusion in this debate.
Like Descartes, Tebye is looking for some rock to ground his knowledge. He fails to recognize is the nature of certainty. Certainty is contextual, meaning not that it's subjective but that it depends on our conditions, especially the range of our experiences and the scope of our knowledge. For example, look at the recent events in Waco, Texas. Can we be certain of what happened? Given what the major media has said, no. There's too much seemingly conflicting evidence. Obviously, some of this so called evidence is false or is being misinterpreted. The context here includes the fact that our government has a history of covering up its mistakes and the conflicting stories from various sources (some of which have vested interests in the outcome). However, all is not lost. In this context we can be certain of a few things, such as the need for more evidence and the probability that our government is lying (to some extent).
The problem with Descartes' "I think therefore I am" is that thinking can err, therefore it does not provide the absolute certainty Cartesian doubt requires. So, Descartes fails by his own standard!
"Consciousness presupposes existence", not "perhaps" as Tebye spinelessly tags on, but absolutely, undeniably, unequivocally. As I said: "existence... is the most fundamental assumption of all knowledge." Or, in the words of Leonard Peikoff, "Before one can consider any other issue, before one can ask what things there are or what problems men face learning about them, before one can discuss what one knows or how one knows it -- first, there must be something... If not, there is nothing to consider or to know." (from Objectivism: The Philosophy of Ayn Rand) Unperceived existence is not a "rational contradiction" or a contradiction in any sense of the word. If Tebye is trying to sneak idealism in through the back door, he'll have to do better than this.
On patterns, Tebye slips into representationalism, the view that perceptions are inner representations "related to the external object in much the same way a painting is related to the scene it portrays." (PAR) The point is any pattern we perceive in the world is the result of the intrinsic attributes of the objects we perceive and our means of perception. Perception is not passive reflection nor is it arbitrary invention of the external object. It's an active process of integration.
This applies to colors. Color is one form in which we perceive the subatomic structure of objects. The colors we see depend on the light reflected or emitted by an object and the way this light is detected and processed by our visual systems. Kelley goes over this in detail. I'm surprised Tebye missed the point that color is NOT intrinsic to the objects themselves. A cucumber is not dark green. Dark green is the color seen if we look at a cucumber under daylight conditions. Color perception is not the perception of the wavelength of light. Our visual systems process massive amounts of data, taking into account background illumination and the wavelengths of light received from the cucumber. Often, the perception of a particular color is the result of this system taking into account several different wavelengths of light from the same object as well as the background. The best example of this is purple, which does not correspond to any particular wavelength but is a mixture of both reds and blues.
It's not what Tebye believes about the sensory awareness of infants, but what the research shows that is important. Ayn Rand, in Introduction to Objectivist Epistemology, was in error when she wrote that infants are aware of the world by means of sensations, but later on they use perceptions. All the evidence I've seen shows that infants from the earliest age are aware by means of perception. Tebye quotes Kelley out of context. What Kelley was declaring in his section on perceptual learning was not that perception is a learned skill but that certain types of perceptual acuity -- such as wine tasting and music appreciation -- are fine tuned through a consciously active process. In order to fine tune your perceptual abilities you have to already be working on the perceptual level. This means in general perception can not be learned. (If not, Hume's criticisms of sensationalism would apply, viz., there's no nonarbitrary way for one to consciously put sensations together to form perceptions.)
Again, Tebye misses the point about defining "mind." What is a proper definition? "Definition requires breaking something down in its fundamentals." (UCT) Perhaps it would be more accurate to say that a definition identifies essentials. (See Leonard Peikoff's Objectivism: The Philosophy of Ayn Rand for a longer account.) Defining mind as "the functioning of the brain" has several flaws. One, it is not a definition in terms of essentials. Two, "the functioning of the brain" is wide open to misinterpretation. Is any functioning of the brain meant to be mind. I doubt Tebye would say so. He's assuming too much about a field where our ignorance is huge. Third, he's already loading the dice in favor of materialism. (Note: neither Objectivism or realism are forms of materialism.) How does he know that perhaps brain and mind aren't aspects of some other underlying phenomena? Fourth, we have direct knowledge of our own minds, while any knowledge of the mind as being somehow related to the brain relies on a mountain of inductions and hypotheses. No doubt, these can all be true, but then we must recognize that epistemologically and temporally, our knowledge of the latter depends on the former. Nor would Tebye's definition make the mind any less real. A flame is still real even though we understand the process of combustion better than the first man who saw fire.
Consciousness and awareness, for our purposes here are one and the same. While there are degrees of awareness, ranging from total unconsciousness to full focus, there is no such thing as being "not consciously aware". This is a blatant contradiction in terms. What is possible, and maybe he's hinting at this, is to be aware of something, say, the truck that roared past my window, focusing totally on it and not being aware of other things, such as my awareness of the truck or my posture or my breathing.
I would not call "lapses of awareness" "part-time psychoses." Rather, I would call them sleep or unconsciousness. A lapse of awareness is not the same as a faulty awareness, nor is forgetfulness a form of mental illness -- at least not in its everyday form. One thing that needs to be identified here is that humans are not born knowing how to operate their minds. It's a pain-staking process to focus one's mind. Sure, even infants can perceive, but I am talking about anything above the level of perception.
Sure, the questions are important and we might not get the answers without asking questions. If the latter are so important Tebye should ask them instead of throwing around cliches.
Tebye thinks nothing of creating hypothetical models then holding them up as absolutes to judge reality by. For example, he talks of constructing models of spacetime in which there is no motion. This may be a fruitful means of studying some of the problems of physics, but it is an abstract model. There's no compelling reason to believe it is true. Such models are not bases for rewriting reality.
We can use our imaginations to create many different models, e.g., models of a flatland-style universe in which there is no motion. This does not mean an actual flatland exists or that if it did exist it has the properties we attribute. What's the point of such models? Is it only to engage our fancy and to use against our philosophical opponents? I think they have a valid purpose aside from these. We can explore certain properties of reality (or of our ideas of reality) by reducing the things we have to deal with. Again, this is not a license to edit reality or to confuse reality with any given model.
Tebye's sense of humor is no laughing matter. Philosophy is not to be taken lightly because ideas have consequences. One need only look at how the history of the world is awash with blood, blood shed over ideas, to see how important philosophy is. What is the point of self-mockery? Is it not to undercut responsible thought and action!?! Don't laugh at yourself! Try to rise above and correct your faults. What deeper philosophical problem does it reveal? It reveals that people aren't taking ideas seriously and are, thereby, evading the issues -- in many cases are life-or-death issues!