Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!watmath!clyde!rutgers!husc6!seismo!mcvax!lambert From: lambert@mcvax.UUCP Newsgroups: comp.ai,comp.cog-eng Subject: Re: Searle, Turing, Symbols, Categories Message-ID: <7158@boring.mcvax.UUCP> Date: Sat, 22-Nov-86 07:13:02 EST Article-I.D.: boring.7158 Posted: Sat Nov 22 07:13:02 1986 Date-Received: Sun, 23-Nov-86 04:29:29 EST References: <158@mind.UUCP> <150@cwrudg.UUCP> <160@mind.UUCP> <2495@utai.UUCP> <215@mind.UUCP> <229@mind.UUCP> Reply-To: lambert@boring.uucp (Lambert Meertens) Organization: CWI, Amsterdam Lines: 194 Keywords: appetite, consciousness, self-model, illusion Summary: How do we know "mind" isn't an illusion? Xref: watmath comp.ai:56 comp.cog-eng:13 Apparently-To: rnews@mcvax In article <229@mind.UUCP> harnad@mind.UUCP (Stevan Harnad) writes: > I know directly that my > performance is caused by my mind, and I infer that my > mind is caused by my brain. I'll go even further (now that we're > steeped in phenomenology): It is part of my EXPERIENCE of my behavior > that it is caused by my mind. [I happen to believe (inferentially) that > "free will" is an illusion, but I admit it's a phenomenological fact > that free will sure doesn't FEEL like an illusion.] We do not experience our > performance in the passive way that we experience sensory input. We > experience it AS something we (our minds) are CAUSING. (In fact, that's > probably the source of our intuitions about what causation IS. I'll > return to this later.) I hope I am not suffering from a terrible disease like incipient schizophrenia, but for me it is not the case that I perceive/experience/ am-directly-aware-of my performance being caused by anything. It just happens. I have some indirect evidence that there is some relation between the performance I can watch happening and some sensations (such as anxiety or happiness) that I can somehow experience directly whereas others have no such direct access and can only infer the presence or absence of these sensations within me by circumstantial evidence. How do I know I have a mind? This reminds me of the question put to a priest (teaching religion) by one of the pupils: "Father, how do we know that people have a soul?" "Well," said the priest, "here I have a card in memory of Klaas de Vries. Look, here it says: `Pray for the soul of Klaas de Vries.' They wouldn't put that there if people had no souls, would they?" There is something funny with this debate: it is hardly translatable into Dutch. The problem is that if you look up "mind" in an English-Dutch dictionary, some eight translations are suggested, none of which has "mind" as their primary meaning if translated back to English, except for idiomatic reasons (like in: "So many men, so many minds"). Instead, we find (1) memory; (2) meaning; (3) thoughts; (4) ghost; (5) soul; (6) understanding; (7) attention; (8) desire. Of these, I contend, "ghost" and "soul" are closest in meaning if someone says: "I know I have mind. But how can I know that other people have minds?" OK, if you substitute "consciousness" for "mind", then this does no essential harm to the debate and things become translatable to Dutch. What you gain, is that you loose the suggestion evoked (at least to me) by the word "mind" that it is something perhaps not quite, but almost, tangible, something that you could lock up in a box, or cut in three, or take a picture of with a camera using aura-sensitive film. "Consciousness" is more like "appetite": you can have it and you can loose it, but even though it is functionally related to bodily organs, you normally don't think of it as something located somewhere. Does our appetite cause our eating? ("My appetite made me eat too much.") How can we know for sure that other people have appetites as well? I propose to consider the question, "Can machines have an appetite?" 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." 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 in the middle of a forest makes a sound in the absence of creatures capable of hearing. That is a matter of the most useful (convenient) definition. 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). How can you know that you have been conscious of something that you reacted upon? You stopped in front of a red light (or so others tell you) while involved in a heated argument. You have no remembrance whatsoever of that light being red, or of your slowing down (or of having been at that intersection at all). Maybe your attention was so completely focussed on the argument that the reaction to the traffic light was fully automatic. Now someone tells you: No, it wasn't automatic. You muttered something unfriendly about that other car driver who made as if he was going to drive on and then suddenly braked. And now, zzzap!, the whole episode pops up in your mind. You remember that car, the intersection, the traffic light, its jumping to red, the slight annoyance at not making it, and the anger about that *@#$%!!! other driver whose car you almost crashed into. Maybe everything is conscious. Maybe stones are conscious of lying on the ground, being kicked against, being picked up. Their problem is, they can hardly tell us. The other problem is, they have no memory (lacking an appropriate substrate for storing a trace of these experiences). They are like us with that traffic light, if there hadn't been that other car with that idiot driver. Even if we experience something consciously, if we loose 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. Now maybe everything we experience is stored in memory. It may be that we cannot recall it like that, but using special techniques (hypnosis, electro- stimulation, mnemonic drugs) it could be retrieved. On the other hand, it is more plausible that not quite everything is stored in memory, since that would require a tremendous channel width for storing things, which is not really functional, or, at least, there are presumably better trade-offs in terms of survival capability given a limited bran capacity. 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? That position is maintainable, but it is not very useful in the sense that the word "consciousness" looses its meaning; it becomes coextensive with "existence". We "loose" our bicameral minds, Freud, and all that jazz. More useful, then, to use "consciousness" only for experiences that are, somehow, recallable. It makes sense that not all, not most of, but some of 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. Being the kind of animal homo is, it also makes sense to store material that is useful for the refinement of the model we have of our inside world, that which we think of as "ourselves". After all, we consult that model to pre-evaluate the outcome of certain alternatives. If we don't "know" ourselves, we are bound to do things (take on a responsibility, marry someone, etc., things with a long-term commitment) that will lead us unto suffering. (We do these things anyway, and one of the causes is that we don't know ourselves that well.) So a lot of the things that go on "in the front of our minds" are stored away, and are recallable. And it is only because of this recallability that we can say that these things were "in the front of our minds", or "in our minds" at all. Imagine now a machine programmed to "eat" and also to keep up some dinner conversation. It has some rules built-in about etiquette like that it is impolite to eat too much, but also some parameter varying in time to model "hunger", and a rule IF hunger THEN eat. It just happens that the machine is very, very hungry. There is a conflict here, but fortunately our machine is equipped with a conflict-resolution module (CRM) that uses fuzzy logic to get an outcome for conflicting rules. The outcome here is that the machine eats more than is polite. The dinner-conversation module (DCM) has no direct interface with the CRM, but it is supplied with the resultant behaviour as part of its input data and so it concludes (using the rule base) that it is not behaving too politely. Speaking anthropomorphically, we would say that the machine is feeling uneasy about it. Actually, a flag "uneasiness" is raised, and the DCM is programmed to do something about it. Using the rule base, the DCM finds a rule that tells it that uneasiness about being impolite can be reduced by apologizing about it. The apology submodule (ASM) is invoked, which discovers that a casual apology will do in this case, one form of which is just to state an appropriate cause for the inappropriate behaviour. The rule base tells ASM that PROBABLE CAUSE OF eat IS appetite, (next to tape-worms, but these are measured as less appropriate under the circumstances), so "<; >" is passed back to DCM, which, after invoking appropriate syntactic transformations, utters the unforgettable words: "Boy, do I have an appetite today." How different are we from that machine? If we keep wolfing down food at a dinner, knowing that we are misbehaving (or just substitute any behaviour that you are prone to and that you realize is just not quite right--come on, there must be something), is the choice made the result of a conscious process? I think it is not. I have no reason to think it is. Even if we ponder a question consciously ("Whether 'tis nobler in the mind to suffer ..."), 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". We can as it were instantly focus our attention on things that we are not conscious of most of the time (the sensation of sitting on a chair, the colour of the sky). This means merely that we can influence which part of the processes going on all the time get the preferential treatment of being stored away for future reference. The ability to do so is clearly functional, notwithstanding the fact that we can make a non-functional use of it. This is not different from the fact that 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. 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, and it will probably attribute some of its darker sides (about which it comes to conclude that it feels guilt, from which it deduces that it has a conscience) to lack of affection in childhood or "wrong wiring". Is it mistaken then? Is the machine taken in by an illusion? I propose to consider the question, "Can machines have illusions?" -- Lambert Meertens, CWI, Amsterdam; lambert@mcvax.UUCP