NICK@AI.AI.MIT.EDU (Nick Papadakis) (06/06/88)
Date: Sat, 4 Jun 88 14:21 EDT From: George McKee <mckee%corwin.ccs.northeastern.edu@RELAY.CS.NET> To: ailist@mc.lcs.mit.edu Subject: Artificial Free Will -- what's it good for? Obviously many people think that the question of whether or not humans have free will is important to a lot of people, and thinking about how it could be implemented in a computer program is an effective way to clarify exactly what we're talking about. I think the McDermott's contributions show this -- they're getting pretty close to pseudocode that you could think about translating into executable programs. (But just to put in my historical two cents, I first saw this kind of analysis in a proceedings of the Pontifical Academy of Sciences article by D.M.MacKay in about 1968.) If free will is programmable, it's appropriate to then ask "why bother?", and "how will we recognize success?", i.e. to make explicit the scientific motivation for such a project, and the methodology used to evaluate it. I can see two potential reasons to work on building free will into a computer system: (1) formalizing free will into a program will finally show us the structure of an aspect of the human mind that's been confusing to philosophers and psychologists for thousands of years. (2) free-will-competent computer systems will have some valuable abilities missing from systems without free will. Reason 1 is unquestionably important to the cognitive sciences, and insofar as AI programs are an essential tool to cognitive scientists, *writing* a program that includes free will as part of its structure might be a worthwhile project. But *executing* a program embodying free will won't necessarly show us anything that we didn't know already. Free will in its sense as a consequence of the incompleteness of an individual's self-model has an essentially personal character, that doesn't get out into behavior except as verbal behavior in arguments about whether it exists at all. For instance, I haven't noticed in this discussion any mention of how you recognize free will in anyone other than yourself. If you can't tell whether I have free will or not, how will you recognize if my program has it without looking at the code? And if you always need to look at the code, what's the point in actually running the program, except for other, irrelevant reasons? (This same argument applies to consciousness, and explains why I, and maybe others out there as well, after sketching out some pseudocode that would have some conscious notion of its own structure, decided to leave implementation to the people who work on the formal semantics of reflective languages like "3lisp" or "brown". (See the proceedings of the Lisp and FP conferences, but be careful to avoid thinking about multiprocessing while reading them.)) Which brings us to Reason 2, and free will from the perspective of pure, pragmatic AI. As far as I can tell, the only way free will can affect behavior is by making it unpredictable. But since there are many other, easier ways to get unpredictability without having to invoke the demoniacal (or is it oracular?) Free Will, I'm back to "why bother?" again. Unpredictability in behavior is certainly valuable to an autonomous organism in a dangerous environment, both as an individual (e.g. a rabbit trying to outrun a hungry fox) and as a group (e.g. a plant species trying to find a less-crowded ecological niche), but in spite of my use of the word "trying" this doesn't need to involve any will, free or otherwise. In highly sophisticated systems like human societies, where statements of ability (like diplomas :-) are often effectively equivalent to demonstrations of ability, claiming "I have Free Will, you'll fail if you try to predict/control my behavior!" might well be quite effective in fending off a coercive challenge. But computer systems aren't in this kind of social situation (at least the ones I work with aren't). In fact they are designed to be as predictable as possible, and when they aren't, it indicates a failure either of understanding or in design. So again, I don't see the need for Artificial Free Will, fake or real. My background is largely psychology, so I think that it's valuable to understand how it is that people feel that their behavior is fundamentally unconstrained by external forces, especially social ones. But I also don't think that this illusion has any primary adaptive value, and I don't think there's anything to be gained by giving it to a computer. If this is true, then the proper place for this discussion is some cognitive-science list, which I'd be happy to read if I knew where to send my subscription request. - George McKee NU Computer Science