Form is Emptiness, Emptiness is Form.
The Heart Sutra
The following essay was written shortly after I finished my dissertation and obtained my Ph.D. in philosophy, in 1985. The idea was to begin presenting the theories of the dissertation piece by piece in journal articles. Ontological undecidability was a concept discussed in the Introduction to the dissertation.
I began submitting the essay to philosophy journals, particularly those that had been recommended to me. It was rejected for publication again and again. This was not unusual, since most of the submissions to philosophy journals were rejected at the time.
Although rejections to academic journals had traditionally been accompanied by readers reports, with criticisms of the submissions, this was no longer always done in philosophy, and most of the rejections I received were of summary and opaque form. There were still some journals, however, that returned readers reports. This made it possible to meet specific criticisms and to resubmit the essay, hopefully with the objections, material or otherwise, remedied.
This never worked; and the essay continued to be rejected, sometimes after being resubmitted twice, with additional modifications. But there was something funny about this. If one has criticisms of a work, and states those objections, and then the objections are met, but then other objections are always found, this begins to look like there is something about the piece that the critic just doesn't like but that he would not or could not express openly.
So I began to wonder if the stated criticisms of the readers reports were honest, or just pretexts for rejection. What could it be about the essay that the readers just didn't like? Well, I had run into something like this already. My experience as a graduate student had not always been an easy one, since more than once I gotten involved in serious disagreements, if not clashes, with professors. This often seemed to boil down to the problem that we did not agree on how to do philosophy. They didn't like the way I was doing it, and, fair enough, I didn't like the way they were doing it.
A memorable example was in a seminar on ethics I was in once. One day, I presented a paper, which set off a lively discussion in the class. Afterwards, however, the professor said that the essay was not quite the kind of thing he was looking for -- I think he was running the seminar to promote the sort of Aristotelian virtue ethics that was becoming popular at the time. As the class adjourned, one of the other students came up to me said that, regardless of what the professor had said, it had actually been one of the more interesting discussions that we had had all semester. The classes were often, indeed, pretty dull, and whatever the professor had been looking for, it did not sound like it was very interesting to a number of the students.
This didn't actually develop into a row with the professor; and in 1981 he even loaned me his office while he was on sabbatical. It was there that I began to write my dissertation. He was in fact a nice person. This was Edmund Pincoffs (d.1991). Having open, personal arguments with these professors, as it happens, was rare, although the worst one was my very first semester at the University of Texas, in 1975, which made me wonder if I was going to fit in well enough to continue there. On the other hand, when I knew that a professor, like Robert Solomon, whose seminar on Hegel I attended, was on an entirely different wavelength, and we had almost nothing in common in terms of our attitudes towards philosophy, I didn't see much point in making an issue of it. I followed what I would later learn was the advice of Franklin and Jefferson, "never to contradict anybody," but that, "Conviction is the effect of our own dispassionate reasoning, either in solitude, or weighing within ourselves, dispassionately, what we hear from others, standing uncommitted in argument ourselves" [letter of Jefferson, 24 November 1808]. Solomon was not impressed with the paper I wrote for the class, but he didn't seriously hassle me about it. Recently, watching the lectures on Existentialism that he did for The Teaching Company, I am confirmed in my impression, particularly by his treatment of Nietzsche, that he was really not a very good philosopher -- although honored with teaching awards and the subject of learned discussions at conferences.
So if journals were not going to accept my work, perhaps because it was just not the sort of thing they were interested in, what was I to do? Fate intervened, and by the purest good luck I was hired to teach at Los Angeles Valley College, which was no more than three blocks from where I was living and where I then remained until retiring in 2009. Since this was a community college, I did not need to worry about publications. Instead, I ended up writing about what I was teaching, which is what professors used to do, in the days before World War II, when teaching loads at universities were not uncommonly what mine was at Valley, namely 15 hours a week or more. Immanuel Kant himself was plagued with a heavy teaching load (up to 21 hours a week, I believe, something I did one semester), whose content was expected to be established material (such as the Leibnizian Christian Wolff) and not his own work. Later, we see that Alfred North Whitehead's Process and Reality is essentially the lectures he gave at Harvard on metaphysics.
They do say, after all, that you never really understand something until you teach it. For me, although I was never able to simply teach a class in metaphysics, it was the most helpful to teach ethics, where I was able to steadily develop my ideas, often in contast to the content of the ethics textbook that I initially inherited with the class. Some community colleges require teachers to use the books that their department has chosen for the course. I never had to do that at Valley, but I also never found an ethics book that I liked better. When it eventually went out of print, I already had enough of my own material, which beginning in 1996 could be posted on line, that I could dispense with a textbook altogether -- our bookstore was willing to print out and bind my materials for students who, in those early days, did not have ready access to the Internet.
Thus, "Ontological Undecidability" came to be self-published in The Proceedings of the Friesian School. This does not mean that it has been taken any more seriously in academic philosophy; but, after my initial experience trying to get it published in the ordinary way, I was confirmed in my sense that established academic philosophy perhaps would never be interested in the ideas of the Friesian School. After all, something like this had already been the experience of Schopenhauer, who was buried under the Hegelian tide for decades and actually had to finance the publication of the second edition of The World as Will and Representation himself . This occasioned his famously bitter remarks about the "professors of philosophy." Although I had more of a career in academic philosophy than Schopenhauer did, it was obvious that no one really needed to take seriously an instructor at a community college; and at the venues I attended with philosophy faculty from research institutions, I often felt that they condescended to be amused by me, even people I thought were being friendly on a personal level. On the other hand, the efforts of the students of Leonard Nelson after World War II to cultivate academic interest in him otherwise had come to naught -- absolutely so in Britain and America. For all their efforts and enthusiasm, all they got out of it was... me. At Texas, there actually were a couple of people, like Irwin Lieb, who knew about Nelson and were pleased that I was working on him.
So I do not need to experience Schopenhauer's bitterness. Now, when I read people like John Seale or Ronald Dworkin expressing palpable sophistries, or I am horrified at the celebration of the Nazi, Martin Heidegger, I don't know whether to feel pity or shame. I don't understand what universe people can be inhabiting who say that the greatest philosophers of the 20th Century were Heidegger and Ludwig Wittgenstein. Philosophy is in terrible shape if that is the best we can do.
Since "Ontological Undecidability" was rewritten more than once, with perhaps pointless modifications to suit people who weren't going to like it anyway, what follows is not the original essay, which may have been lost in the sort of shuffle of papers that we had to deal with before computers and word processing. The theory, however, has not been compromised in any way, which may have been the problem.
When the editor of Ratio said that the essay was simply too long for his journal, I quickly wrote "Non-Intuitive Immediate Knowledge," which was then accepted for publication just as quickly. It was featured in the final issue of Ratio before the journal was taken over by Basil Blackwell and lost its last connection to the Friesian School. In a tragic irony, the very title of the essay was mistranslated in the German edition of Ratio, demonstrating that neither the translator nor the editor were actually familiar with the philosophical terminology used by Leonard Nelson in German. There could have been no clearer example or symbol of the decline of Friesian fortunes.
The epigraph below from Chih-i was added many years after the original essay was posted, and its relevance to Undecidability is left to the inference of the reader. The early date of the first posting of the essay is also why it is devoid the the links that are featured in other pages of this website (or even in this editorial note).
One may say neither that the one mind is prior and all dharmas posterior nor that all dharmas are prior and the one mind posterior.... If one derives all dharmas from the one mind, this is a vertical relationship. If the mind all at once contains all dharmas, this is a horizontal relationship. Neither vertical nor horizontal will do. All one can say is that the mind is all dharmas, and all dharmas are the mind. Therefore the relationship is neither vertical nor horizontal, neither the same nor different. It is obscure, subtle and profound in the extreme. Knowledge cannot know it, nor can words speak it. Herein lies the reason for its being called "the realm of the inconceivable."
Chih-i (or Zhiyi, 538-597 AD), founder of Chinese T'ien-t'ai Buddhism, quoted by Jacqueline I. Stone, Original Enlightenment and the Transformation of Medieval Japanese Buddhism, Kuroda Institute, University of Hawai'i Press, 1999, p. 179
The purpose of this essay is to introduce an idea, a simple idea; but it sometimes happens that the simplest ideas are the most difficult, and the most powerful. The most important dilemma facing modern ontology is whether the objects that we perceive around us in the world are externally real, just as we see them , or only phenomenal contents of our own minds. The idea here is that this is a dilemma that cannot be resolved, or cannot be decided, in a generally applicable way. Consequently, the theory will be called "ontological undecidability." While our usual feeling is that there is something disappointing and discouraging about dilemmas that cannot be resolved, as though a kind of dead end is being reached, so that we must go back and start all over again in our inquiries, the view taken here is that undecidability involves no disappointment and actually opens up possibilities that otherwise cannot be appreciated.
Undecidability in various forms is no longer unusual or surprising in modern thought. Gödel has made undecidable propositions an essential part of mathematics and logic--undecidable within an axiomatic system but true on some external basis. In the same way there are many paradoxes of undecidability in quantum mechanics. The Uncertainty Principle was originally conceived as expressing no more than a limitation on our knowledge. Reality in itself need not have been uncertain. However, it soon came about in the theories of virtual particles, tunnelling, the paradox of Schrödinger's Cat, etc. that the uncertainty principle seemed to allow things to happen in reality that something that was a mere limitation in our knowledge could not explain. A most clearly undecidable quantum issue is that we are unable to determine whether the fundamental objects of physics are waves or point particles--leaving us with the "wave-particle duality." In general, quantum mechanics posits an interdependence between internal and external, knowledge and reality, that leaves us with paradoxical questions about how things can be real and independent of knowledge and at the same time be depend on the conditions of our knowing. Many, including Einstein, have found such a system disturbing, even incomprehensible [Now we have Roger Penrose's searching discussion in The Emperor's New Mind, chapter 6, "Quantum magic and quantum mystery," Oxford 1990.].
Although ontological undecidability posits a relationship between reality and knowledge similar to quantum uncertainty, such a precedent of course proves nothing in the present case. It is only an analogy. When it comes to proof of undecidability in regard to realism and phenomenalism, the ideal way would be to demonstrate, as with the paradox of the Liar, that stipulating the truth of one side of the dilemma always implies its own falsehood and the truth of the other side. [The Liar may be put thus: Is the statement, "This statement is false," true or false? If it is true, then what it states, that it is false, must be true. Therefore, it is false. But, if it is false, then what it states, that it is false, must be false. And if it is false to say it is false, then it must be true.] The Liar, however, may be without a truth value, or may simply be false, neither of which is quite right. Complementarity in quantum mechanics does make the wave and particle natures of matter both true: depending on the circumstances, matter must be dealt with as though wave-like or particle-like (and not both at the same time). What is undecidable is what matter really is like apart from any observation by us. This is much like ontological undecidability, since realism and phenomenalism are both true, just not at the same time and in the same way. Niels Borhs motto for the princple of complentarity expresses it quite well: Contraria non contradictoria sed complementa sunt; "opposites are not contradictories but complements." [quoted in "P.A.M. Dirac and the Beauty of Physics," R. Corby Hovis and Helge Kragh, Scientific American, May 1993, p. 104.] It may seem too convenient that we can treat objects as phenomenal for some purposes and real for others, but that is precisely what is called for: that is precisely the convenience of the theory, and that is where the analogy with the wave-particle duality is the strongest. It is also where undecidability functionally duplicates Kant's transcendental idealism, as we shall see.
§2. On Method
The theory of this paper is presented and argued in a way that is different from what has become common in modern analytic philosophy. I did not set out to write a paper that made a point of being unusual. It is simply written in a way that seemed to me clear, relevant, and discursive. Nevertheless, the manner in which the paper is argued turned out to be sufficiently unusual that it has been criticized and seriously faulted for it. Readers evidently would have preferred a different kind of work. The kind of work they might have preferred, so far as I can tell, is one I have no intention of producing. The fashion in which the argument for ontological undecidability is presented is deliberate and intentional, and the paper is done this way for practical and for theoretical reasons.
The practical reasons are that academic philosophy by its interests, style, and jargon has closed itself off from the audience of educated persons who used to read philosophy. The quest for clarity and rigor inspired by the example of mathematics and logic, which has moved many recent philosophers to actually write with a stilted, mechanical awkwardness reminiscent of translations into logical symbolism [deliberately and explicitly so for the "Neologistic Typographical School of Philosophy"], has instead often only resulted in stupifying impenetrability, sterility, and meaninglessness. It is an unpleasant thing to say, or to hear, but the truth is that the simplest way to be absolutely clear is to say as little as possible. This kind of reduction is not quite what Thomas Jefferson meant when he said that the better something is understood, the more simply it can be explained. This is not explaining things more simply; it is not explaining them at all.
Philosophy itself has become shattered into a kaleidioscope of seemingly trivial issues and esoteric debates, which serves to shelter thinkers from saying much of anything recognizably meaningful. As Allan Bloom says, "Positivism and ordinary language analysis have long dominated, although they are on the decline and evidently being replaced by nothing. These are simply methods of a sort, and they repel students who come with the humanizing questions. Professors of these schools simply would not and could not talk about anything important, and they themselves do not represent a philosophic life for the students" [The Closing of the American Mind, p. 378]. Karl Popper says, "...what I regard as the ultimate cause of the dissolution of the Vienna Circle and of Logical Positivism is not its various grave mistakes of doctrine....but a decline of interest in the great problems: the concentration upon minutiae (upon "puzzles") and especially upon the meanings of words; in brief, its scholasticism. This was inherited by its successors, in England and in the United States" [Unended Quest, Open Court, 1990; p.90)]. The whole mechanism of academic philosophy--peer review, conferences, journals, etc.--militates against efforts at systematization or holism, let alone an actual concern with the educated public or a posterity of readers who will go from all the great philosophers of the past to whatever we happen to be producing now. We may end up with little either in the way of literary achievement or of profoundly creative ideas with which to impress them. "Literary achievement" is, of course, nothing that anyone in philosophy need be serious about, and "creative ideas" are liable to be dismissed either as vaporous speculations or damnable system building (which I have heard called "Weltanschauung mongering").
Nevertheless, this is usually all taken as a virtue: the professionalization of philosophy. But it is no more than the characteristic of a system of bureaucratic privilege that seeks to create mysteries closed to the uninitiated and can sneer at anyone who does not have the specialized inside knowledge necessary to understand the opaque allusions and hermetic jargon. It may be objected that the technical and sophisticated character of modern philosophical problems requires such specialized knowledge and terminology. To an extent that may be true; but it is also true that we can look back now on the ways in which something like Logical Positivism was presented and argued--the source of so much of the style and technique of philosophical discourse today--and state what was fundamentally wrong and even absurd about that school in ways a twelve-year-old could understand [e.g. that the verificationist criterion of meaning would disqualify its own doctrine from meaningfulness. Wittgenstein at least recognized that the theory of the Tractatus made itself senseless, but neither he nor his admirers seemed to be much bothered by this at the time--although this drove someone like Karl Popper to fury at such foolishness (cf. The Open Society and Its Enemies Vol II, footnote 51 to Chapter 11, pp. 296-299).]. Those same objections could have been thus simply stated at the time, or at the turn of the century, or in Kant's day, but somehow amid all the sophistication and self-importance of the discussions the simplest and most obvious things escaped notice. Much the same kind of thing seems to continue. Losing track of the forest for all the trees is a required skill for much of academic philosophy.
These are the usual effects of professionalism, and this has actually happened before: giving us all the negative connotations of the word "scholasticism." It is not an accident that modern philosophy began with a series of philosophers, from Decartes to Hume, who had no association with academic life and who wrote and published without passing through the clumsy incestuous strainer of peer review. Later, the consequences that the association of philosophy with state academic institutions quickly had were immediately and appallingly apparent to Schopenhauer [And appreciated by Popper, The Open Society etc., Vol. II, pp. 32-33.]. Now, the baleful popularity of philosophers like Nietzsche and Wittgenstein carries with it the irony that neither of them conformed to the curriculum and standards (especially of publication) of present academic advancement, or even personal conduct. Those very standards now carry with them the assumption that good philosophy cannot be done any other way, even while it is the creativity and eccentricity of those two that excite fascination. The professional esotericism of academic philosophy is thus affirmed in word and claim but refuted by its own icons.
There has already been a strong reaction against the sterility of analytic and academic philosophy in the farcical word play, lofty irrationalism, and pathetic politicized ideologies of deconstruction [As Allan Bloom says, "This school is called Deconstructionism, and it is the last, predictable, stage in the suppression of reason and the denial of the possibility of truth in the name of philosophy" (Ibid. , p. 379).]. That has mostly bypassed philosophy, but its effect has been felt, as a creative and self-confident movement is sure to be against a field that has slowly been drained of life. Deconstruction, indeed, can style itself as a direct reaction against the very positivism that did so much to create the bloodlessness and schizophrenic dissociation of analytic philosophy. The theoretical reasons for the procedure of this essay, therefore, must follow from a reconsideration of the nature of rational philosophic argument.
The key issue was already appreciated by Aristotle: that not everything can be proven. If an infinite regress of reasons is to be avoided, there must be first principles of demonstration whose justification does not come from deductive inference. This is actually reaffirmed by Gödel's Proof, whose point is simply that even mathematics must contain a dimension of meaning and justification that will always transcend the structure of any formalized system [See Penrose, "...it seems to me that it is a clear consequence of the Gödel argument that the concept of mathematical truth cannot be encapsulated in any formalistic scheme" (ibid. p.111) and "...the concept of mathematical truth is only partly accessible by the means of formal argument" (ibid. p.122)]. The need for non-inferential justification, although occasionally recognized, nevertheless has made little progress beyond Aristotle's conviction that first priniciples are known to be true through intuitive self-evidence . A great step came with Kant, whose category of synthetic a priori propositions allowed for first principles that were necessarily true but not self-evident; but confusion and argument about this very point, and Kant's own confusions about how such propositons actually are justified, has largely prevented the promise of his insight from being fulfilled [The most serious creative treatment of the question of justification and of first principles of demonstration has come with Jakob Fries, Leonard Nelson, and Karl Popper.].
Here, that issue cannot be pursued much further. But its influence is felt in this exposition, which relies more on history, especially Kant, and less on exhaustive argument. The reader may find the use of history and the absence of the expected degree of argumentation irritating, but this procedure is deliberate and purposeful. The approach is a dual one, consisting of what may be called the "hermeneutic" and "foundational" projects. The hermeneutic project simply aims at a new understanding or a new interpretation of existence and knowledge as involving undecidably real and phenomenal aspects. The hermeneutic project explains, discusses, and suggests. It does not argue in much of a recognizable way. The foundational project, on the other hand, does aim at a ground for proof and a claim of knowledge. Both projects are needed for a complete theory, but the need, desire, or call for proof only is relevant once the nature of the theory is understood. Truths, even in mathematics, as I have indicated, can exist without their proofs; but a proof (such as the Ontological Argument) without an understanding of the nature of the issue results only in hair-splitting and confusion. Such results sometimes seem to have become the principal content of academic philosophy.
The hermeneutic project in the long run is therefore really the greatest challenge for a philosophical theory. Through it the theory is introduced and explained, showing what kind of explanatory power it can have. If that power is great enough, if undecidability really offers a truly different avenue out of the dilemma of realism and phenomenalism, that by itself should make the theory sufficiently interesting for the purposes of discussion. Anyone who likes a theory can always provide their own arguments for it, but the theory must be there in the first place. The great mathematician Gauss once said, "I have had my results for a long time; but I do not yet know how I am to arrive at them" [«Meine Resultate habe ich längst, ich weiß nur noch nicht, wie ich zu ihnen gelangen werde.» Quoted by Leonard Nelson in "Von der Kunst, zu philosophieren," in Vom Selbstvertrauen der Vernunft, p. 145, Felix Meiner Verlag 1975, translated in Socratic Method and Critical Philosophy, p. 89, Dover 1965.]; and I suspect that Gauss was far more likely to decisively substantiate his "results" than any of us are with philosophical issues. Thus the first move will be just to present undecidability and see what it gets us.
§3. Kant's Ontological Undecidability
Although the name of ontological undecidability may be unfamiliar, it need not be thought of as a new theoretical device in philosophy. The best precedent is to be found in Kant. Indeed, Kant comes so close to a functional equivalent of ontological undecidability that what follows may be considered something of a meditation on Kant's transcendental idealism and the whole treatment a running dialogue with Kant. There is some danger in this, for Kant means many things to many people. The issue revolves narrowly enough, however, around the status of things in themselves. I suspect that the reader who finds Kant's conception of things in themselves perfectly satisfactory as it stands, or who believes that things in themselves can be completely discarded without loss, will have greater difficulty appreciating the undecidability of realism and phenomenalism and the truth in both perspectives that cannot be reduced to the other. Nevertheless, my concern is certainly not to assume the truth of anything Kant says.
One of the most important moments in Kant's Critique of Pure Reason comes at page 104 of the first edition where Kant says, "At this point we must make clear to ourselves what me mean by the expression 'an object of representations'." [Immanuel Kant, Critique of Pure Reason translated by Norman Kemp Smith, St. Martin's Press, New York, 1965, p. 134.] Kant quickly provides his answer, the historic introduction of phenomenalism:
It is easily seen that this object must be thought only as something in general = x, since outside our knowledge we have nothing which we could set over against this knowledge as corresponding to it....
But it is clear that, since we have to deal only with the manifold of our representations, and since that x (this object) which corresponds to them is nothing to us--being, as it is, something that has to be distinct from all our representations--the unity which the object makes necessary can be nothing else than the formal unity of consciousness in the synthesis of the manifold of representations. [Ibid., pp. 134-5.]
The difficulty for Kant of this powerful thesis, which after all, is the basis of his entire argument for the existence of synthetic a priori knowledge , is that it seems to render superfluous his continued adherence to the notion of things in themselves. A thing in itself is in fact the object = x which stands outside of our knowledge, over and against our representations, and which in some way we suppose corresponds to the knowledge that we have of it. That would be the straightforward Cartesian view of things. In Kant's theory, however, all those functions of an "object" have been taken over by the object-forming functions of synthesis, and Kant's own awareness of this is evident enough in his conclusion that things in themselves are not known by us and so do not, in any familiar fashion, correspond to our representations after all.
The question then is why the thing in itself remains in the theory. To subsequent generations it has seemed that Kant ends up with a precarious, paradoxical, and perhaps even incoherent dualism between things in themselves and the phenomenal objects produced by synthesis. Kant has two orders of objects, the phenomenal and the noumenal; yet noting the drift of Kant's own argument, we would be justified in regarding noumenal objects as redundant artifacts of the more naive stages of his own thought. Things in themselves or noumenal objects only seem to weaken the sense of "empirical realism" for which Kant was striving, confusing us that perceptual objects are "merely" phenomenal and so subjective, while what the theory has done is indeed to have made "clear to ourselves what we mean by the expression 'an object of representations'" and to have endowed our conception of phenomenal objects with the essence of that meaning.
The thought here, however, is that Kant was right to retain his dualism. It is one indication of how delicate is Kant's balancing act in the equation of "transcendental idealism" and "empirical realism" that it is the "realism" of the latter that even those sympathetic with Kant have trouble taking seriously. Thus, for all his appreciation of it, Schopenhauer regarded Kant's doctrine simply as a version of Berkeley's subjective idealism [In which, of course, there is simply no separate existence of material objects--cf. Arthur Schopenhauer, The World as Will and Representation Volume I translated by E.F.J. Payne, Dover Publications, New York, 1966, pp. 3, 424, & 434-5. Schopenhauer, however, preserves a different sense of the thing in itself and is not a subjective idealist.]. In undecidability the issue is also what we mean by "an object of representations," and the result is the same juxtaposition of real and phenomenal as in Kant's doctrine. It is essential, therefore, that just how "realism" and "phenomenalism" are going to be distinguished from each other be pinpointed, both in Kant and in the larger picture of knowledge. Let me do this now by saying that the defining criterion for the difference, and the origin and essential feature of the whole matter, is as a question of existence: that we are all distinct, separate, and independent in existence from the things (except the body) that we know through perception. They can exist when we don't; and we can exist when they don't; and our veridical perceptions are supposed to represent them. Realism thus basically takes the independence and separateness of existence seriously, while phenomenalism balks at it because it is "distinct from all our representations." Kant says,
Either the object alone must make the representation possible, or the representation alone must make the object possible....In the latter case, representation in itself does not produce its object in so far as existence is concerned... [Kant, op. cit., p. 125.]
The difficulty of phenomenalism, where "the representation alone must make the object possible," is that this feature of existence is easily lost. Indeed, if what phenomenalism means is that the reality of an object is exhausted by its features in the representation of a subject, then it is hard to see how this differs from solipsism or subjective idealism. As Kant says,
What is first given to us is appearance. When combined with consciousness, it is called perception. (Save through its relation to a consciousness that is at least possible, appearance could never be for us an object of knowledge, and so would be nothing to us; and since it has in itself no objective reality, but exists only in being known, it would be nothing at all.) [Kant, op. cit., pp. 141-42.]
These are chilling words--"it would be nothing at all"--but they apply to "appearances" and so to the phenomenal objects which the "combination" with consciousness, through synthesis, posits in perception. At the same time, Kant, in clearly distinguishing his empirical realism from "empirical idealism" (i.e. Berkeley) [cf. Henry E. Allison, Kant's Transcendental Idealism, Yale University Press, New Haven, 1983, pp. 14-34.], certainly thought that he had avoided the subjectivist alternative of reducing all of reality to something that is "nothing at all" apart from us. Existence is what stands to differentiate the real from the merely phenomenal.
§4. The Problem of Knowledge
Arguments have been offered, beginning with Kant, that self-knowledge of the subject is secondary to and dependent upon objective representation, or that an objective world is something presupposed by features of subjective representation, or that language is only meaningful when referring to public entities; but however persuasive or actually cogent, such arguments are not really responsive to the essential dilemma of the Cartesian problem of knowledge, which is how objects, which are distinct, separate, and external in existence to a subject, can possibly affect or communicate with the subject such that the subject comes to possess perceptual knowledge that truthfully, faithfully, and reliably represents the objects. To be responsive, such arguments must address the hiddenness of external existence. Berkeley used that hiddenness to reject the reality of matter; but Kant evidently felt that there was some irreducible kernel of truth in the hiddenness that could not be entirely accounted for by phenomenal objectivity. The hiddenness was the existence of the object precisely as a separate reality--the existence that the representation alone cannot "produce."
A recent philosopher such as Richard Rorty does not believe that we need to be responsive to the Cartesian problem of knowledge--even though his thesis results, as he says, in "persons without minds" [Richard Rorty, Philosophy and the Mirror of Nature, Princeton University Press, Princeton, 1979, p. 70. My various references to Rorty concern the doctrine of this book; and I have chosen Rorty for such references because he seems to me to typify these kinds of tendencies in 20th century philosophy]. The Cartesian problem of knowledge, however, is not so easily dismissed if one is concerned to avoid reductionism. Indeed it plays upon the very fundamental ontology of the human condition to which the theory of ontological undecidability is addressed: As soon as we distinguish ourselves and the phenomena of our perception from the independent things that we perceive, we are free to doubt that the character or even the existence of those things is as we picture it. The occurrence of dreams and hallucinations must persuade us that at least sometimes there is nothing corresponding to our representations, and it is not at all clear how we can presume to know a priori by what criteria we should judge where hallucination leaves off and veridical perception begins. Furthermore, when we consider that we expect external objects to cause our perceptions, or at least our sensations, by the physical affection of our senses, then we have a further basis for doubt in that a cause is never more than sufficient to its effects: if different causes can produce the same effect, then it is perfectly conceivable that perception is caused, not by the objects in question, but by the direct agency of God, by mental illness, by extraterrestrials, or, as Descartes might have it, by the Deceiving Demon.
At the same time, if we allow that hallucinations exist, we must also allow that there is a distinction between phenomenal representations that correspond to real existence and phenomenal representations that do not. Of course we then want to know what is really the difference between the existing things that we see and the non-existing things that we see. We cannot be reassured by producing the real objects independent of our experience, for we do not exist outside our experience to examine them. Thus, in principle, the very thing, existence, that distinguishes existing from non-existing phenomena is inaccessible. That might make it seem so much the worse for real existence, if eliminating this hidden existence did not mean that hallucination and veridical experience were equivalent [...and if we were not so familiar with things like virtual particles, which have a happy and secure place in quantum mechanics despite being neither accessible nor even "real"]. Some might be willing to say that all experience is just hallucination, but this would certainly eliminate a distinction of rather great importance in ordinary life. Nevertheless, the fundamental conviction of pure phenomenalism is that the inaccessibility of this real external existence makes realism fundamentally a hopeless doctrine: there is just no way that we can base our knowledge on something that is essentially outside any means of contact with it. Especially when the "real things" are supposed to be what we actually experience every day in ordinary life, it is perplexing how they then end up in principle outside that experience.
Kant's conclusion that we cannot know things in themselves, even though he offers the substitute of phenomenal knowledge, is really an admission that he could not solve the Cartesian problem of knowledge. His confidence in the objectivity of phenomenal knowledge, on the other hand, seems due to his confidence in the universality and objectivity of the forms of reason, expressed in the necessities of synthesis [Where the more modern equivalent might be a belief that language embodies and imposes a form and an "objectivity" on the world that the world itself may not possess]; but this is surely a far more questionable matter than a simple confidence in external objects. Somewhere along the line, it is tempting to think, this has all gotten turned around. For something so fundamental as perceptual knowledge and our awareness of the external world, there must be some simple truth that, once we have hit upon it, will make clear both what the justification of perceptual knowledge is and why it has been such a confusing matter for so long to many of the greatest minds in the history of philosophy. That simple truth must not be self-evident or even particularly obvious. It may even take a good deal of getting used to. We might even expect to be discomfited by it, since it would express a perspective on the matter that has previously been overlooked. The theory of ontological undecidability is here offered as such a simple truth, with all the curiosity of these paradoxical overtones.
§5. The Conflict of Fundamental Beliefs
The real basis of the problem of knowledge is that the requirements of ontology and epistemology pull in different directions. We seem to have a fundamental ontological belief--the "question of existence" above--that real things exist independently of each other. They can come into existence and pass out of existence, and this can occur without affecting other things in so far as they exist. Why this belief occurs is an aspect of the matter that I will not be able to investigate very deeply here. I would have to regard it as reflecting a synthetic a priori axiom, a Kantian condition of the possibility of experience, while an opposing view, Rorty's for instance, might take it to be no more than a contingent artifact of a historically limited and dated Cartesian "language game." Be that as it may, such a belief seems to me to underlie, actually or potentially as a Socratic presupposition, many commonsense and philosophically sophisticated views about the world, and I will take it to stand as the fundamental common principle of all forms of ontological realism. The belief may be formalized into a special principle (principium) of the Separability of Substance: that the existence of a substantial object, as opposed to a quality or attribute, means that it can be separated from other objects, to go on to its own isolated existential fate. For us this means that we can move away from objects that we perceive and that they, and we, will continue to exist nonetheless. This view stands in stark contradiction to the thesis of subjective idealism, let alone solipsism. And such a fundamental ontological belief is what I take to underlie the correspondence theory of truth, that if knowledge is to conform to truth, then it somehow must represent and correspond to the real things that exist independently of us.
Phenomenalism in its simplest form involves the rejection of the separability of substance. There is more to such a move, however, than mere dissatisfaction with separability. This rejection must be based on some positive conviction, and it is: besides our fundamental ontological belief, we also have a fundamental epistemological belief that there is a connection between external things and ourselves, between object and subject, such that we are directly or immediately acquainted with such external things. This is "naive realism" in an epistemological sense, and that is a revealing label: phenomenalism is not based on some arcane philosophical rejection of common sense. Phenomenalists can regard their views as essential more realistic than ontological realism by their faithfulness to our fundamental epistemological belief. That epistemological belief may thus be formulated as the principle (principium) of Epistemological Realism, that the real objects of knowledge are directly available for our inspection. The coherence theory of truth is more conformable with this viewpoint than with separability, in the sense that, to be true, knowledge merely need be made coherent or consistent with and among its various accessible elements, the phenomenal objects of perception and thought.
Modern philosophy has found for itself a world of trouble because epistemological realism runs afoul of the separability of substance; for if we take separability seriously, we feel compelled to conclude with Descartes that we cannot be directly or immediately acquainted with external objects. We can only be directly or immediately acquainted with our own perceptions, our own sensations, or our own states of mind, all of which depend on our own existence and so do not need to be mediated by whatever processes or relations bridge the ontological gap between subject and object. This all makes it sound as though we are acquainted with the external world by inference, making an intellectual leap from perceptions, sensations, etc. to the external things themselves. Such an inference, however, does not withstand much examination, and the result is an incongruous and curious one. If we are naively acquainted with the world by inference, it is strange that such an inference should be so natural, powerful, and persuasive before reflection yet so unconvincing when examined. It is so powerful, indeed, that we are far less likely (with Descartes) to doubt the ontological belief and the reality of the objects than we are to doubt the epistemological belief and the connection between subject and object, even though scepticism about the epistemological belief might reasonably be expected to undercut any confidence we might have in the ontological belief. This is the paradox of the conflict between the beliefs: we allow the separability of substance to introduce doubt about the reliability of the knowledge whereby we were in the first place acquainted with external and separable objects. As we lose confidence in the reliability of our knowledge, we then lose confidence in the separate existence, which confidence in the first place created the scepticism about our knowledge. We are confused by our own confidence.
§6. Epistemological Priority and Intentionality
Kant allowed to each belief its due, and this is the real strength, insight, and wisdom of his theory: to the epistemological belief, direct acquaintance with phenomenal objects; to the ontological belief, the independence and separability of things in themselves. We can avoid the strange and unsatisfactory aspects of Kant's theory, resolve the Cartesian paradoxes of knowledge, and approach undecidability from a different direction, by reëxamining the priorities of the fundamental beliefs.
In Kant, as in Descartes, the ontological belief still has its mediaeval priority over the epistemological belief, and the meaning of that as well as the evidence of it is found clearly enough in the unknowable existence of the things in themselves. Despite the deserved reputations of both Descartes and Kant as having pushed epistemological questions to the front of philosophy, their results are still spoiled by their failure to make their revolutions thoroughgoing enough. They are still part of the transition from the primacy of metaphysics--ontological "first philosophy"--to the primacy of epistemology--Cartesian epistemological "first philosophy." If a way can be seen to it, the thing to try would seem to be to go all the way, attribute complete priority to the epistemological belief, and see if this improves the situation. The relation between subject and object would thus become the basic and unalterable given, to which the independence of objects must be subordinated--much as Schopenhauer considered subject and object to be mere "halves" of representation as such [Schopenhauer, op. cit., p. 5.]. In this way the world, after a fashion, is turned inside out, a mere epiphenomenal relation becomes the foundation, and we do not allow our naive sense of our direct and immediate acquaintance with the objects of experience to be undercut by any subsequent thoughts we may have about the nature of the existence of those objects or their relationship to the subject.
A focus on the relation between subject and object, as itself the primary and fundamental given, should serve to bring to our attention the truly distinctive characteristic of our perceptions: their inherent duality. Such duality, called by Robert Paul Wolff the "double nature of representation" [Robert Paul Wolff, Kant's Theory of Mental Activity, Harvard University Press, Cambridge, 1963, p. 109.], means that the forms and sensible qualities that are the content of perception are taken by us to belong both to the external objects that are known by means of them and to our selves which are the ontological substrate for their existence as the contents of perception. This should be stated rather differently than Wolff does:
Representations, viewed in one light, are merely the contents of our consciousness, the immediate objects of awareness. But at the same time they perform the function of referring beyond themselves to the objects which they purport to represent. [Ibid., p. 109.]
We should conclude instead that representations as such are not the immediate objects of awareness, in the ontologically unreformed way that Wolff has put it. We should take ourselves naively and commonsensically to be directly aware of the objects to which representations refer, eliminating a redundant multiplication of "objects" which does not occur in common sense or ordinary language. This has been noted by others. The duality consists in our realization, once we reflect on our acts of awareness, not that they happen to refer to external things, which is what we believed all along, but that they consist entirely of the contents of our consciousness--the realization of which Cartesian truth leaves nearly everyone rather surprised and puzzled, wondering how the relationship with the objects was possible in the first place. In the face of this, a favored move of 20th century philosophy, a move common to Wittgenstein, Ryle, and Rorty, is to wipe out the private internal realm of the Cartesian subject--and so of the sense of representations as representations--altogether. It nevertheless seems fair to me to say that the Cartesian dilemma, however paradoxical, is more squarely addressed to the human condition than that sort of reductionism.
The double nature of representations is conformable to the important notion of intentionality, as discussed by Brentano, Husserl, and others. For Husserl consciousness is "consciousness of" [Edmund Husserl, Cartesian Meditations translated by Dorion Cairns, Martinus Nijhoff, The Hague, 1970, p. 33.]. The contents of consciousness are always referred to something else. Brentano says:
Every mental phenomenon is characterized by what the Scholastics of the Middle Ages called the intentional (or mental) inexistence of an object, and what we might call, though not wholly unambiguously, reference to a content, direction toward an object. [Franz Brentano, Psychology from an Empirical Standpoint, Routledge & Kegan Paul, London, 1973, p. 88.]
The trouble with the phenomenological notion of intentionality is that, indeed, it is an attribute of mental phenomena, thereby firmly preserving the priority of the ontological belief in the independence of objects: the existence of the objects of my perception, although intended by them, still has a purely external and perhaps accidental connection to them. Phenomenology seems to avoid the difficulties involved in this by simply determining not to worry about them. Giving priority to the relation between subject and object, on the other hand, we should say that the existence of an object is just as subordinate to the relation as is the existence of the subject. The sensible contents of consciousness are of objects and so are perceived by us as attributes and qualities of those objects. The reds that I perceive are the reds of red things; and as such they are ontologically dependent on them and obtain their reality and existence from those substantially independent objects. Such is the notion of realism of objects and perceptual attributes. With our focus on the relation of our epistemological belief, we do not allow the realism of our perception to be compromised by the reflection that the reds that I perceive are phantasmata of my sense organs and so only exist because I exist, not because external things exist. Consciousness exists in so far as we exist, yet the cognitive content of consciousness exists in so far as its objects exist. As we are drawn naively to realism, so are we drawn by reflection and the realization of the dependence of our experience on our own existence to phenomenalism.
§7. Ontological Undecidability
The inevitable question then is: To which existence does the sensible content of perception really belong? Are the reds really attributes of independent external objects or are they really subjective percepts that, as mental contents, characterize my own existence? The antireductionist answer should be that, for veridical perception, we cannot decide. The content of the relation of perception between subject and object can be assigned by reflection indifferently to either object or subject. This is the result for ontology of our conceding priority to our epistemological belief: ontological undecidability. By this principle, which in effect does no more than couple the notion of epistemological priority with the double nature of representation, the dilemmas of Descartes and Kant can be resolved. Any violence it does is to our ontological belief: we feel compelled to assign the content of representation to either object or subject; it cannot belong to both and it cannot simply hover between them. But it does. For between them is the relation; and undecidability therefore carries out a form of Copernican Revolution, one in which the previously peripheral and dependent thing, the relation, is turned into what is central and foundational. What we then must do is just ask whether this, however paradoxical, makes more sense than the traditional difficulties created by the priority of the ontological belief.
The major traditional difficulty is that once the content of perception is conceded to the object or to the subject, this inevitably leads to the ontological subordination of subject to object or object to subject: to materialism, wherein the subject is an epiphenomenon of the object, or to idealism, wherein the object is an epiphenomenon of the subject. Each in their own way, these are very disturbing ontological positions--materialism because it substitutes an ultimate stuff that we cannot even inspect as such for the consciousness that is the whole of our experience of ourselves and the world; idealism because it seems to present us a bizarre and speculative choice between solipsism, a Berkeleian plurality of presumably immortal souls, or some sort of mystical metaconsciousness or Hegelian Absolute (an extrapolation of Kantian phenomenalism). These are all alternatives that truly seem as far or further from common sense than ontological undecidability. But with undecidability, we are not forced into a choice among them; and, conceding priority or ultimacy to neither subject nor object, we do not need to reduce one to an epiphenomenon of the other--even though we are still free to say that they must in some sense correspond to each other. It is no accident that similar benefits follow from Kant's transcendental idealism, in which empirical objects are in much the same way real and phenomenal--despite the confusing pull of a wish to say that noumenal objects are what are really real.
Materialism and idealism are good candidates for a Kantian ontological Antinomy, and this suggests the best formal argument for undecidability. If the basic ontological and epistemological beliefs above are equally basic, and if each taken by itself does logically result in ontological materialism or idealism, respectively, and if each of these conspicuously leaves out a fundamental and indispensable feature of human existence or common sense, then clearly the basic beliefs must be reconciled. That can be done in one of two ways: Hume's way, which involves a Skeptical suspension of judgment--"no matter, never mind"--and simply sets aside traditional notions of substance, etc.; and Kant's way, which combines the real and phenomenal in some novel fashion. Kant's clearly is the creative and ambitious approach and holds out the promise that even if it does not work perfectly, there may be some other way to reproduce its virtues, avoiding its faults. Just how that might work need not even be specified; but with ontological undecidability we now can make a specification, namely by ruling out Kant's double order of objects while preserving both the fundamental realistic sense of things in themselves and the epistemological realism of phenomenal experience.
The form of an Antinomy, as we shall see, is the most appropriate for an argument for undecidability. Behind materialism and idealism, behind realism and phenomenalism, there are the two fundamental beliefs of the separability of substance and epistemological realism. The argument should be based on those principles, and the ontological Antinomy consequently will take this form:
|Thesis: That the real objects of experience are separate from us.||Antithesis: That we are directly acquainted with the real objects of experience.|
|Reductio ad absurdum: But, if they are separate from us, we can only be immediately acquainted with our own minds, not with external objects. Thus, we can only know about external objects inferentially, and these inferences, from effect to cause, are not logically compelling. Therefore, we cannot know, nor have sufficient reason to believe, that the real objects of experience are separate from us.||Reductio ad absurdum: But, our perceptions are actually only contents of our own minds, dependent on our own existence, not on the existence of anything external to us. Thus, if we rule out solipsism, we must make inferences from our mental contents to real external objects. Therefore, we are not directly acquainted with the real objects of experience.|
|Corollary: But, if what we know is not separate from us (as concluded), and we have real perceptual knowledge (non-scepticism), then we are directly acquainted with the real objects of experience (the antithesis).||Corollary: But, if we are not directly acquainted with the real objects of experience (as concluded), and they exist (non-solipsism), then the real objects of experience are separate from us (the thesis).|
Each thesis, of course, fails through some overt or covert use of its antithesis. This is not strictly the form of a Kantian Antinomy, where the antithesis is simply the contradiction of the thesis and each thesis is internally consistent. But this is actually better for undecidability: it is more like the form of the Liar, in which each thesis is a reductio ad absurdum of itself that also implies the antithesis. An argument of this form thus promises to be the most elegant kind of argument for the purpose here, since, like the Liar, it is the proof of its own undecidability. In the sense that our fundamental ontological and epistemological beliefs underlie realism and phenomenalism, or materialism and idealism, the argument can in principle be extended to provide explicit Antinomies for those alternatives. The logical force of Kantian Antinomies, of course, was to establish transcendental idealism--that the contradiction can be avoided by confining knowledge to the phenomenal limits of a possible experience, ruling out transcendental realism (that we know things in themselves), while the paradox of the Antinomies arises from Reason itself and is real and necessary, ruling out empirical idealism (that reality is merely phenomenal). Similarly, the ontological Antinomy of undecidability has the force of ruling out both realism and phenomenalism as adequate, independent truths.
Just as we can give an Kantian Antinomy for ontological undecidability, so can we also give an axiomatic diagram as used by Leonard Nelson. Here we are given the basic choice between internal and external, with the added premise that there is substantive existence, i.e. we can understand the metaphysical substratum of existence (substances). Rejecting internal substance, the soul, we are driven to Materialism. Rejecting external substance, matter, we are driven to Idealism. Rejecting both, we are driven to Positivism, which denies metaphysics altogether, rendering the search for "substantive existence" as a pseudo-problem. These have been the great metaphysical alternatives of the last century or so, idealism (Hegel), materialism (Marxism), and positivism (Comte, Ayer). A fourth conclusion, however, is possible, which is to reject the choice between internal and external and deny that substantive existence is either of them. This is rather stronger than what, for the moment, we will consider in relation to Undecidability, though it is the ultimate resolution of the dilemma. We are left with a kind of phenomenological suspension of judgment because we don't have the metaphysical categories here for what the "third thing" would be that is neither internal nor external. Here we must consider first that is not so much neither internal nor external but both that we are stuck with.
§8. The Two Perspectives of Undecidable Ontology
Each with equal dignity, subject and object form the basis for us, thanks to undecidability, for two equal and interchangeable but radically and wholly different perspectives on the world: the external, which essentially treats all things as objects and ignores (or reduces to an epiphenomenon) the subject, and the internal, which treats the whole of experience and objective reality as, at least initially, a content, as representation, of the subject. These two perspectives can serve to define the fundamental difference between science and philosophy, much as Rorty believes has actually been the case in modern philosophy. Science takes an external perspective. The view is that of a disembodied observer to whom any real subject, in so far as it is physically present anywhere, is merely one object among many. The relation of knowledge or perception is an external one to be handled in terms of the causal relation holding between objects and the sensory organs and neurophysiological information processing systems of biological organisms--all of which is a matter for psychology and of no concern or consequence for the discoveries of any other sciences. Such an external perspective can easily be adopted into epistemology and given a philosophic form, as in a self-professedly "externalist" theory like that of D.M. Armstrong [cf. D.M. Armstrong, ibid., p. 157.]. Such theories, together with the practice of science, are unobjectionable on their own terms. They are not, however, a response to the Cartesian problem of knowledge and belong more to philosophy of science, or to a kind of philosophy that regards scientific knowledge as the paradigm of all knowledge, than to a traditional and independent discipline of philosophy that is going to be able to give more than reductionistic answers in areas like metaphysics and value theory.
When philosophy begins with the internal perspective, it is immediately faced with the Cartesian problem of knowledge and with the reality of the human condition in so far as our existence is embodied in the frail and transient form of individual consciousness. With undecidability, however, it cannot be argued, as Descartes does, that we know the internal better than the external (they are equal) or that representations as such are foundational for an inferred knowledge of the external world. These errors have been avoided; and now the internal perspective, indeed, means simply to balance the internal and external as the external approach of science, or of behavioristic systems, cannot. An orientation in terms of the two perspectives on reality is, curiously, the basis for the categorization of psychological types by C.G. Jung:
...in one case an outward movement of interest towards the object, and in the other a movement of interest away from the object to the subject and his own psychological processes....
But in general one could say that the introverted standpoint is one which sets the ego and the subjective psychological process above the object and the objective process, or at any rate seeks to hold its ground against the object. [C.G. Jung, Psychological Types (Collected Works Volume 6), Bollingen Series XX, Princeton University Press, Princeton, pp. 4-5.]
With ontological undecidability we have halted, at least for theoretical purposes, any movement towards the subject or towards the object that does not pay the other its due, which is the kind of credit that Jung gave to Kant himself. Holding its ground against the object, philosophy no longer need worry about becoming "scientific" or about distinguishing itself from science by its method or by some object (e.g. language, meaning) that has not entirely become subject to science; for it can in a sense consider the very same objects as science, or the very same contents of representation, only with the radical difference that these are not taken to be external and physical things but are instead considered from the virtual solipsism of the individual subject. That solipsism is no longer an enemy to be avoided, refuted, or ignored; it is simply that which gives us our own individual consciousness as the absolutely unique and unparalleled thing that, for us, it is--the window on objective existence that at the same time is the whole of our own existence as subjects, individuals, persons, and, indeed, beings at all. This privacy, individuality, and personality is something that an anti-Cartesian behaviorism, whether inspired by linguistic philosophy, deconstruction, or experimental psychology, is at pains to erase--thereby cutting off cognition from the most important truths of our existence, the truths of being and value that are the most starkly illuminated and motivated by the privacy, individuality, absoluteness, and utter internality of our own deaths: for only in death is the existence of the Cartesian subject actually erased.
§9. Hallucination and Truth
It was noted above that the existence of hallucinations is an important datum for the manner in which we conceive of the relation between real and phenomenal. But we are still left without clear criteria to distinguish between veridical perception and hallucinatory perception. How do we know when there is and when there is not a real object? This weakness on the objective side of perception indicates that the relation between subject and object is not one that, even with undecidability, is ontologically symmetrical. The difficulties that have always resulted from this asymmetry merit our most serious consideration. For instance, Richard Fumerton believes that "an argument from the possibility of hallucination" proves that naive realism is wrong, meaning that, "we are never directly acquainted with the fact that a physical object exists..." [Richard A. Fumerton, Metaphysical and Epistemological Problems of Perception, University of Nebraska Press, Lincoln and London, 1985, p. 85.]. Otherwise, Fumerton's argument turns on the same point as the argument given above, that a cause is only sufficient to its effect, that we conceive of perceptions as caused, and so that an evidently veridical perception can conceivably be caused by something other than the objects it seems to represent. In our experience we are, perhaps, directly acquainted with the facts concerning our mental states, but the possibility that experiences are hallucinations proves that we cannot be directly acquainted with the facts concerning physical objects that, beyond our reckoning, may or may not be causes of our experiences.
The problem with this kind of argument is that it proves too much. Taken with sufficient seriousness, it is an argument against the possibility of knowledge in general, not just against naive realism--a throwback to before Kant and to the most perplexing aspect of pure Cartesianism. Fumerton cannot recover from the wider implications of such an argument, and his own honest conclusions are that scepticism is difficult to refute, that he doesn't see how we can do so, and that perhaps a philosopher shouldn't adopt some sort of program to refute scepticism--philosophy just can't provide the sort of justification of belief that we would like [Ibid., pp. 24-32, 193-4.]. The weakness of such conclusions is not surprising: in denying realism, Fumerton demands inferential justifications for ordinary empirical beliefs, and once launched upon that sea, there is little hope of a shore being reached without the surreptitious introduction of some ground of justification unrecognized by the procedure of daily cognition. Kant's substitute realism in the form of an empirical realism of phenomenal objects was not so much a substitute as one side of the truth. Real objects are phenomenal, as we ordinarily treat them; and the things that appear are, most of the time, real. That is just the point.
In combining phenomenalism and realism, both Kant and ontological undecidability also combine the theories of truth as correspondence and as coherence--a move conformable to the Friesian theory of truth advocated by Leonard Nelson [Leonard Nelson, "The Critical Method and the Relation of Psychology to Philosophy," Socratic Method and Critical Philosophy, Dover Publications, New York, 1965, p. 117.]. In the face of a radical possibility of hallucinations, the general coherence of our experience is our only practical and theoretical recourse. The sole practical recourse in the privacy of the subject, coherence is theoretically justified if the real and external objects to which truth corresponds are also undecidably phenomenal and internal. Fumerton, in order to disarm himself, in spite of himself, against scepticism, must ignore the phenomenal immanence of physical things and embrace the bizarre notion that common sense is persuaded of the existence of physical objects, in general and in particular, by inferences that cannot stand up to the most half-hearted critique. What the argument from the possibility of hallucinations gets us is a dream of insanity--where we cannot rely on the plain meaning of the coherence of our ordinary experience. Thus undecidability finds itself in the always happy situation of having its cake and eating it too, adopting common sense notions of correspondence and externality while at the same time being able to draw on phenomenal coherence in order to avoid the nastiest enigmas of Cartesian epistemology. And again, this does no more than reproduce the virtues of Kant's transcendental idealism.
The principle of ontological undecidability does embody a peculiar link between reality and knowledge similar to that noted in quantum mechanics above. We understand real objects in their own terms as independent and separable substances; yet real objects are also the phenomenal objects that are present in perception, and these have an essential epistemological dependence on the subject. We are free to ask whether this is a peculiarity of our knowledge, that we can't help but conceive of objects except as objects-for-a-subject, since it is impossible for us to have knowledge outside of our subjective viewpoint, or whether it reflects something essential about reality, that consciousness and subjectivity are things that are just as fundamental ontologically as is the external, physical, and objective. Is undecidability merely a limitation on our knowledge? Or does it reflect, as it is reasonable to ask about quantum uncertainty, some basic truth in which there is no indecision and no uncertainty?
Such questions are what remain to ontological undecidability of Kant's questions about things in themselves. As with Kant, this empirical realism of undecidability does not establish phenomenal objects, or individual minds, as absolute existents. Their reality is relative to each other, even while the substantial separability of phenomenal objects requires a realism that prevents the theory from drifting into a mere phenomenalism, with a ghostly order of noumenal objects in the background. Instead, undecidability leaves us with an ontological uncertainty based on our alternative perspectives on the world. To the external perspective it is obvious that human beings, although interesting specimens, are not essential to the continuity of existence--they, their works, their knowledge, even their planet could pass away and be erased and the universe would be affected no more than as by a grain of sand vanishing from a beach. Such is the vengeance of the separability of substance. To the internal perspective the entire universe depends on a fragile awareness that is not indifferent either to the universe, itself, or to other conscious beings. Before the age of science all humans liked to think that they were as important in the universe as the universe was in them. Since then we have gone to the opposite extreme, to a possible sense of hopelessness and absurdity as our existence becomes ever more infinitesimal in relation to the vastness of space and time that we have discovered. The real question, however, is not what human existence means to the universe but what the existence of consciousness and subjectivity means to the universe. With ontological undecidability this becomes an open question. It may well be that the human condition, or the condition of conscious being, is not to know whether conscious existence is of some ultimate significance or not--whether minds have some connection to an ontologically absolute existence. It is not unreasonable to hope that they do; but it is unreasonable not to be sobered by the alternative. This is the philosophic equivalent of, as it has been called, the silence of God. And this is what properly remains of the inner mystery of the world that Kant represented by his doctrine of the cognitive transcendence of things in themselves. Instead of the mystery of noumena, however, we have the mystery of ourselves, and of the death that will overtake our consciousness: bringing home to us the "question of existence" in its most compelling Existential form.