Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!rutgers!princeton!mind!harnad From: harnad@mind.UUCP (Stevan Harnad) Newsgroups: comp.ai,comp.cog-eng Subject: Re: Searle, Turing, Symbols, Categories Message-ID: <393@mind.UUCP> Date: Fri, 28-Nov-86 01:27:20 EST Article-I.D.: mind.393 Posted: Fri Nov 28 01:27:20 1986 Date-Received: Fri, 28-Nov-86 20:23:41 EST References: <158@mind.UUCP> <150@cwrudg.UUCP> <160@mind.UUCP> <2495@utai.UUCP> <7158@boring.mcvax.UUCP> Organization: Cognitive Science, Princeton University Lines: 303 Keywords: appetite, consciousness, self-model, illusion Summary: Inferring that others have conscious experience Xref: mnetor comp.ai:72 comp.cog-eng:18 Lambert Meertens (lambert@boring.uucp) of CWI, Amsterdam, writes: > for me it is not the case that I perceive/experience/ > am-directly-aware-of my performance being caused by anything. > It just happens. Phenomenology is of course not something it's easy to settle disagreements about, but I think I can say with some confidence that most people experience their (voluntary) behavior as caused by THEM. My point about free will's being an illusion is a subtler one. I am not doubting that we all experience our voluntary actions as freely willed by ourselves. That EXPERIENCE is certainly real, and no illusion. What I am doubting is that our will is actually the cause of our actions, as it seems to be. I think our actions are caused by our brain activity (and its causes) BEFORE we are aware of having willed them, and that our experience of willing and causing them involves a temporal illusion (see S. Harnad [1982] "Consciousness: An afterthought," Cognition and Brain Theory 5: 29 - 47, and B. Libet [1986] "Unconscious cerebral initiative and the role of conscious will in voluntary action," Behavioral and Brain Sciences 8: 529 - 566.) Of course, my task of supporting this position would be much easier if the phenomenology you describe were more prevalent... > How do I know I have a mind?... The problem is that if you > look up "mind" in an English-Dutch dictionary, some eight > translations are suggested. The mind/body problem is not just a lexical one; nor can it be settled by definitions. The question "How do I know I have a mind?" is synonymous with the question "How do I know I am experiencing anything at all [now, rather than just going through the motions AS IF I were having experience, but in fact being only an insentient automaton]?" And the answer is: By direct, first-hand experience. > "Consciousness" is more like "appetite"... How can we know for > sure that other people have appetites as well?... "Can machines > have an appetite?" I quite agree that consciousness is like appetite. Or, to put it more specifically: If consciousness is the ability to have (or the actual having of) experience in general, appetite is a particular experience most conscious subjects have. And, yes, the same questions that apply to consciousness in general apply to appetite in particular. But I'm afraid that this conclusion was not your objective here... > Now why is consciousness "real", if free will is an illusion? > Or, rather, why should the thesis that consciousness is "real" > be more compelling than the analogous thesis for free will? > In either case, the essential argument is: "Because I [the > proponent of that thesis] have direct, immediate, evidence of it." The difference is that in the case of the (Cartesian) thesis of the reality of consciousness (or mind) the question is whether there is any qualitative, subjective experience going on AT ALL, whereas in the case of the thesis of the reality of free will the question is whether the dictates of a particular CONTENT of experience (namely, the causal impression it gives us) is true of the world. The latter, like the existence of the outside world itself, is amenable to doubt. But the former, namely, THAT we are experiencing anything at all, is not open to doubt, and is settled by the very act of experiencing something. That is the celebrated Cartesian Cogito. > Sometimes we are conscious of certain sensations. Do these > sensations disappear if we are not conscious of them? Or do they go > on on a subconscious level? That is like the question "If a falling > tree..." The following point is crucial to a coherent discussion of the mind/body problem: The notion of an unconscious sensation (or, more generally, an unconscious experience) is a contradiction in terms! [Test it in the form: "unexperienced experience." Whatever might that mean? Don't answer. The Viennese delegation (as Nabokov used to call it) has already made almost a century's worth of hermeneutic hay with the myth of the "subconscious" -- a manifest nonsolution to the mind/body problem that simply consisted of multiplying the mystery by two. The problem isn't the unconscious causation of behavior: If we were all unconscious automata there would be no mind/body problem. The problem is conscious experience. And anthropomorphizing the sizeable portion of our behavior that we DON'T have the illusion of being the cause of is not only no solution to the mind/body problem but not even a contribution to the problem of finding the unconscious causes of behavior -- which calls for cognitive theory, not hermeneutics.] It would be best to stay away from the usually misunderstood and misused problem of the "unheard sound of the falling tree." Typically used to deride philosophers, the unheard last laugh is usually on the derider. > Let us agree that the sensations continue at least if it can be > shown that the person involved keeps behaving as if the concomitant > sensations continued, even though professing in retrospection not > to have been aware of them. So people can be afraid without > realizing it, say, or drive a car without being conscious of the > traffic lights (and still halt for a red light). I'm afraid I can't agree with any of this. A sensation may be experienced and then forgotten, and then perhaps again remembered. That's unproblematic, but that's not the issue here, is it? The issue is either (1) unexperienced sensations (which I suggest is a completely incoherent notion) or (2) unconsciously caused or guided behavior. The latter is of course the category most behavior falls into. So unconscious stopping for a red light is okay; so is unconscious avoidance or even unconscious escape. But unconscious fear is another matter, because fear is an experience, not a behavior (and, as I've argued, the concept of an unconscious experience is self-contradictory). If I may anticipate what I will be saying below: You seem to have altogether too much intuitive confidence in the explanatory power of the concept and phenomenology of memory in your views on the mind/body problem. But the problem is that of immediate, ongoing qualitative experience. Anything else -- including the specifics of the immediate content of the experience (apart from the fact THAT it is an experience) and its relation to the future, the past or the outside world -- is open to doubt and is merely a matter of inference, rather than one of direct, immediate certainty in the way experiential matters are. Hence whereas veridical memories and continuities may indeed happen to be present in our immediate experiences, there is no direct way that we can know that they are in fact veridical. Directly, we know only that they APPEAR to be veridical. But that's how all phenomenological experience is: An experience of how things appear. Sorting out what's what is an indirect, inferential matter, and that includes sorting out the experiences that I experience correctly as remembered from those that are really only "deja vu." (This is what much of the writing on the problem of the continuity of personal identity is concerned with.) > Maybe everything is conscious. Maybe stones are conscious... > Their problem is, they can hardly tell us. The other problem is, > they have no memory... They are like us with that traffic light... > Even if we experience something consciously, if we lose all > remembrance of it, there is no way in which we can tell for sure > that there was a conscious experience. Maybe we can infer > consciousness by an indirect argument, but that doesn't count. > Indirect evidence can be pretty strong, but it can never give > certainty. Barring false memories, we can only be sure if we > remember the experience itself. Stones have worse problems than not being able to tell us they're conscious and not being able to remember. And the mind/problem is not solved by animism (attributing conscious experience to everything); It is merely compounded by it. The question is: Do stones have experiences? I rather doubt it, and feel that a good part of the M/B problem is sorting out the kinds of things that do have experiences from the kinds of things, like stones, that do not (and how, and why, functionally speaking). If we experience something, we experience it consciously. That's what "experience" means. Otherwise it just "happens" to us (e.g., when we're distracted, asleep, comatose or dead), and then we may indeed be like the stone (rather than vice versa). And if we forget an experience, we forget it. So what? Being conscious of it does not consist in or depend on remembering it, but on actually experiencing it at the time. The same is true of remembering a previously forgotten experience: Maybe it was so, maybe it wasn't. The only thing we are directly conscious of is that we experience it AS something remembered. Inference may be involved in trying to determine whether or not a memory is veridical, but it is certainly not involved in determining THAT I am having any particular conscious experience. That fact is ascertained directly. Indeed it is the ONLY fact of consciousness, and it is immediate and incorrigible. The particulars of its content, on the other hand -- what an experience indicates about the outside world, the past, the future, etc. -- are indirect, inferential matters. (To put it another way, there is no way to "bar false memories." Experiences wear their experientiality on their ears, so to speak, but all of the rest of their apparel could be false, and requires inference for indirect confirmation.) > If some things we experience do not leave a recallable trace, then > why should we say that they were experienced consciously? Or, why > shouldn't we maintain the position that stones are conscious > as well?... More useful, then, to use "consciousness" only for > experiences that are, somehow, recallable. These stipulations would be arbitrary (and probably false). Moreover, they would simply fail to be faithful to our direct experience -- to "what it's like" to have an experience. The "recallability" criterion is a (weak) external one we apply to others, and to ourselves when we're wondering whether or not something really happened. But when we're judging whether we're consciously experiencing a tooth-ache NOW, recallability has nothing to do with it. And if we forget the experience (say, because of subsequent anesthesia) and never recall it again, that would not make the original experience any less conscious. > the things that go on in our heads are stored away: in order to use for > determining patterns, for better evaluation of the expected outcome of > alternatives, for collecting material that is useful for the > construction or refinement of the model we have of the outside world, > and so on. All these conjectures about the functions of memory and other cognitive processes are fine, but they do not provide (nor can they provide) the slightest hint as to why all these functional and behavioral objectives are not simply accomplished UNconsciously. This shows as graphically as anything how the mind/body problem is completely bypassed by such functional considerations. (This is also why I have been repeatedly recommending "methodological epiphenomenalism" as a research strategy in cognitive modeling.) > Imagine now a machine programmed to "eat" and also to keep up > some dinner conversation... IF hunger THEN eat... equipped with > a conflict-resolution module... dinner-conversation module... > Speaking anthropomorphically, we would say that the machine is > feeling uneasy... apology submodule... PROBABLE CAUSE OF eat > IS appetite... "<... >" > How different are we from that machine? On the information you give here, the difference is likely to be like night and day. What you have described is a standard anthropomorphic interpretation of simple symbol-manipulations. Overzealous AI workers do it all the time. What I believe is needed is not more over-interpretation of the pathetically simple toy tricks that current programs can perform, but an effort to model life-size performance capacity: The Total Turing Test. That will diminish the degrees of freedom of the model to the size of the normal underdetermination of scientific theories by their data, and it will augment the problem of machine minds to the size of the other-minds problem, with which we are already dealing daily by means of the TTT. In the process of pursuing that distant scientific goal, we may come to know certain constraints on the enterprise, such as: (1) Symbol-manipulation alone is not sufficient to pass the TTT. (2) The capacity to pass the TTT does not arise from a mere accretion of toy modules. (3) There is no autonomous symbolic macromodule or level: Symbolic representations must be grounded in nonsymbolic processes. And if methodological epiphenomenalism is faithfully adhered to, the only interpretative question we will ever need to ask about the mind of the candidate system will be precisely the same one we ask about one another's minds; and it will be answered on precisely the same basis as the one we use daily in dealing with the other-minds problem: the TTT. > if we ponder a question consciously... I think the outcome is not > the result of the conscious process, but, rather, that the > consciousness is a side-effect of the conflict-resolution > process going on. I think the same can be said about all "conscious" > processes. The process is there, anyway; it could (in principle) take > place without leaving a trace in memory, but for functional reasons > it does leave such a trace. And the word we use for these cognitive > processes that we can recall as having taken place is "conscious". Again, your account seems to be influenced by certain notions, such as memory and "conflict-resolution," that appear to be carrying more intuitive weight than they can bear. Not only is the issue not that of "leaving a trace" (as mentioned earlier), but there is no real functional argument here for why all this shouldn't or couldn't be accomplished unconsciously. [However, if you substitute for "side-effect" the word "epiphenomenon," you may be calling things by their proper name, and providing (inadevertently) a perfectly good rationale for ignoring them in trying to devise a model to pass the TTT.] > it is functional that I can raise my arm by "willing" it to raise, > although I can use that ability to raise it gratuitously. If the > free will here is an illusion (which I think is primarily a matter > of how you choose to define something as elusive as "free will"), > then so is the free will to direct your attention now to this, > then to that. Rather than to say that free will is an "illusion", > we might say that it is something that features in the model > people have about "themselves". Similarly, I think it is better to say > that consciousness is not so much an illusion, but rather something to > be found in that model. A relatively recent acquisition of that model is > known as the "subconscious". A quite recent addition are "programs", > "sub-programs", "wrong wiring", etc. My arm seems able to rise in two important ways: voluntarily and involuntarily (I don't know what "gratuitously" means). It is not a matter of definition that we feel as if we are causing the motion in the voluntary case; it is a matter of immediate experience. Whether or not that experience is veridical depends on various other factors, such as the true order of the events in question (brain activity, conscious experience, movement) in real time, and the relation of the experiential to the physical (i.e., whether or not it can be causal). The same question does indeed apply to willed changes in the focus of attention. If free will "is something that features in the model people have of 'themselves'," then the question to ask is whether that model is illusory. Consciousness itself cannot be something found in a model (although the concept of consciousness might be) because consciousness is simple the capacity to have (or the having of) experience. (My responses to the concept of the "subconscious" and the over-interpretation of programs and symbols are described earlier in this module. > A sufficiently "intelligent" machine, able to pass not only the > dinner-conversation test but also a sophisticated Turing test, > must have a model of itself. Using that model, and observing its > own behaviour (including "internal" behaviour!), it will be led to > conclude not only that it has an appetite, but also volition and > awareness...Is it mistaken then? Is the machine taken in by an illusion? > "Can machines have illusions?" What a successful candidate for the TTT will have to have is not something we can decide by introspection. Doing hermeneutics on its putative inner life before we build it would seem to be putting the cart before the horse. The question whether machines can have illusions (or appetites, or fears, etc.) is simply a variant on the basic question of whether any organism or device other than oneself can have experiences. -- Stevan Harnad (609) - 921 7771 {allegra, bellcore, seismo, rutgers, packard} !princeton!mind!harnad harnad%mind@princeton.csnet