The Evidence of the Senses: A Realist Theory of Perception [Englisch] [Taschenbuch]

It is no wonder his work came as such good news to Objectivism; it really is a fairly original attempt to develop a realist theory of perception. However, two common misconceptions must be disposed of at once.

First of all, Kelley's theory is often described as "direct realism." But as we shall see below, his claim to this title is questionable, and at any rate he does not use it himself.

Second, his work is sometimes cited as _the_ "Objectivist theory of perception." It is no such thing.

It wants no little legerdemain to extract a coherent doctrine of perception from the hodgepodge of Rand's own writings on epistemology -- and Kelley, to his credit, does not try. Rand is mentioned only twice in the text and twice more in the footnotes; the word "Objectivism" does not even appear in the index. Like Leonard Peikoff in _Objectivism: The Philosophy of Ayn Rand_, Kelley has taken off on his own -- but unlike Peikoff, he does not present his own theories as Rand's.

As for those theories themselves, they are at least interesting. Kelley is concerned to reject what he calls the "diaphanous model of perception" -- basically the view that, in order for perception to be veridical, the world "out there" must really _be_ just as we perceive it. This model, he argues, lies at the root of both "representationalism" and "epistemological idealism."

In its place he proposes what probably few would deny: that the contents of our experience are the outcome of physico-chemico-bio-psychological causal processes. Taking his lead from Rand, he argues that the fact that experience is caused by such processing does not render it indirect or unreliable. To make this fly, he introduces the notion of a "perceptual form" and argues that, e.g., "coldness" is simply the "form" in which we become _directly_ aware of external temperature (or variations therein).

Now, as I noted above, this is clearly _not_ "direct realism" (which Kelley explicitly rejects under the title of "naive realism" as one side of a false dichotomy stemming from the aforementioned "diaphanous model"). While maintaining that consciousness is not "metaphysically active" (i.e. it does not "create" its own contents), he simultaneously holds that it _is_ "epistemologically active" (in "processing" those contents). I do not see that this distinction can be maintained, but at any rate Kelley recognizes, e.g., the color-experience "blue" as a feature of consciousness _rather than_ as a feature of surfaces "out there"; the "form" or mode in which we perceive various reflectance properties is _not_ identified with the properties themselves.

What he is ultimately after is a theory of perception (which he defines as "the direct awareness of discriminated entities by means of patterns of energy absorption by sense receptors") that will allow him to treat perception as providing "a mode of nonpropositional, noninferential justification."

In order to pull this off, he has to make an extremely dubious distinction between "perceptions" and "perceptual judgments." He acknowledges that other philosophers have rarely seen fit to make this distinction clearly, noting correctly that most have held the element of judgment to be what differentiates perception from sensation in the first place. Kelley argues, in my view unsuccessfully, that his own theory allows him to "distinguish between the judgment and the percept and to consider the former on its own terms."

Why unsuccessfully? Well, I shall not be able to answer completely here, but I shall indicate where some of the problem lies. Kelley makes a strange move in dealing with perception and reference: he argues that whereas "questions of justification normally concern the predicative element of . . . judgment" (when we judge that "x is P," how do we know x is P and not R?), we can raise a similar question about the _subject_ (when we judge that "x is P," how do we know it is x and not y which is P?). This move leaves it open for him to identify "perception" as the means by which we (nonpropositionally and noninferentially) discriminate the subjects of such judgments.

I do not find this even remotely plausible. The "x" Kelley needs here is not a bare particular but a collection of attributes (which seem, by the way, to be universals); "how I know it is x and not y" must be justified in terms of other predicates. That is, the "subject" is unnecessary here; upon analysis, it resolves itself into a vast congeries of predicates. And Kelley's act of perceptual discrimination comes to look a lot more like inference than he thinks it does.

However, Kelley's work is well worth reading, especially as a change of pace from Rand's. He is well versed in the relevant literature and at least displays knowledge of opposing positions (even if, at times, he seems to think it sufficient to describe a position and announce his rejection of it rather than give actual arguments). In short, his scholarship beats the heck out of Rand's.

Readers of this work looking for related viewpoints might want to follow up with some D.M. Armstrong or William Alston, with whom Kelley deals at least briefly in his text. (Oddly, however, Armstrong is not listed in his index.) Those interested in an opposing view will find a good case in the portions of Brand Blanshard's _The Nature of Thought_ devoted to Blanshard's theory of perception. Indeed, I wish Kelley had dealt with these chapters himself rather than spending so much time dealing with post-linguistic-turn "epistemological idealism."

At the same time, is must be recognized that Kelley has not written an introduction to theories of perception or epistemology. Reading this book is no substitute for the later. On the contrary, Kelley's book can be better appreciated with a prior familiarity with more traditional theories of perception. Carefully read, Kelley's book provides a thoughtful counterpoint to the standard theories.

To paraphrase the Scottish philosopher David Hume, who has far more claim to the title of philosopher than either Kelley or Rand, "commit it to flames, for it contains nothing but sophistry and illusion."

A more informative read would be Jeff Walker's book, The Ayn Rand Cult. As for philosophy, stick with the greats: Plato, Aristotle, Descartes, Locke, Hume, Kant, Russell, etc. If you want an introduction to epistemology specifically, Roderick Chisholm's book, Theory of Knowledge, is excellent and unfettered by any hidden agenda.