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From: pindor@gpu.utcc.utoronto.ca (Andrzej Pindor)
Subject: Re: Is Common Sense Explicit or Implicit?
Message-ID: <CwJLJF.Irz@gpu.utcc.utoronto.ca>
Organization: UTCC Public Access
References: <1994Sep21.131455.3228@oracorp.com>
Date: Thu, 22 Sep 1994 17:50:03 GMT
Lines: 152

In article <1994Sep21.131455.3228@oracorp.com>,
Daryl McCullough <daryl@oracorp.com> wrote:
>pindor@gpu.utcc.utoronto.ca (Andrzej Pindor) writes:
>(in response to DrewDalupa <drewdalupa@aol.com>)
>
>>Why did a rock slide down a hillside? Perhaps it had a desire to lower
>>its potential energy? Are you saying that "By denying yourself 
>>the explanation in terms of desire, you leave yourself with that much 
>>less understanding of the world around you"?
>
>Assuming that you don't mean your question about rocks to be simply
>rhetorical, I think I can explain how the explanatory value of desires
>is much better for people than it is for rocks. In the case of a rock,
>saying that the rock desires to lower its potential energy is no more
>informative than simply describing the behavior directly (say, using
>physics). In contrast, consider a statement such as "The man bought a
>gun because he wanted to kill the pesky raccoon." Surely, you must
>admit that this explanation in terms of desire or purpose is much
>better, and more full explanation than saying: "The man bought the gun
>because such and such neuron fired in this or that part of his brain..."
>
You have created a strawman here: since we are unable (at least at present)
to provide such a 'more full explanation' - so the other one is 'better'.

>Using folk psychology to describe human behavior in terms of desires,
>beliefs, emotions, and plans provides *enormous* explanatory and
>predictive power. Of course, there are limits to folk psychology; we
>can't deduce from first principles what desires a person has, or what
>beliefs they hold, and perhaps a more reductionist approach would give
>us a better understanding of such foundations. I don't believe that a
>fuller understanding of how human brains work, even (or especially)
>down to the level of atomic structure would ever supplant folk
>psychological explanations.
>
Depending what you mean by 'supplant'. Knowing what are physico-chemical
reasons of certain behaviors is already being utilized, for instance by
certain medication, prozac being one example, or pharmacological treatments
of sexual offenders - another. In these cases a particular behavior is
explained not by beliefs or desires, but by a chemical state of the brain.

>>The claim you seem to be making is that one needs to accept objectivity of
>>notions like desires (or beliefs) to understand behavior of other people.
>>This would make sense if one had some reasonable way of determining what
>>these beliefs or desires are.
>
>I don't want to make such a strong claim that there is a single,
>objective explanation in terms of beliefs, etc. However, neither is
>there a single, objective explanation of the world in terms of
>physical theories. The best we can say is that a particular theory
>succeeds (at least to a certain extent) in explaining and predicting
>our observations.  In the same way, we can never know for sure what
>another person's beliefs, desires, etc. are, but we can try various
>combinations to see what gives the best theory for describing that
>person's behavior.
>
You are of course right about physical theories, but wrong about the analogy.
Physical theories get any respect only if they cross bounds of a particular
field in which they were postulated as an explanation. If a theory is unable 
to cross such bounds or runs into contradictions when extended outside
these bounds, it is abandoned (e.g. theory of ether).
In case of behavior, beliefs, desires etc. present such flexible combination
that nearly any behavior can be explained, perhaps by postulating yet 
another belief. And if in spite of this flexibility you cannot come up with
an explanation in terms of beliefs etc., you can always say "he/she is out
of his/her mind :-) (or drunk, etc). So the theory is unfalsifiable.
...........
>>explanatory power of these notions? Desires explain behavior, but we
>>know just from behavior what the desires are! Isn't this sadly circular?
>
>No, it is *happily* circular. Let me try on the corresponding claim
>about, say, physics: 
>
>	Some folks (Einstein, Newton, among others) claim
>	that there are these "physical laws" governing the
>	universe, and that if we only knew these laws, we
>	could predict and understand our observations about the
>	universe. But how do people know what these laws
>	are? I am sure that the only way is from observations.
>	Then, however, what is the explanatory power of the
>	notion of "physical law"? Laws of physics explain
>	observations, but we only know from observations what
>	the laws are. Isn't this sadly circular?
>
See above.

>The way in which a theory can be more than the observations
>that gave rise to it is because the observations are just a list
>of particulars, while a theory is a generality. The theory is
>not simply a restatement of the observations, but is an attempt
>to guess the pattern that underlies the observations. In a similar
>way, we may use a person's behavior as a guide in guessing his
>beliefs and desires, but such attributes do not simply restate
>the behavior, they generalize from the behavior, and give us an
>indication of how the person would behave in a new circumstance.
>
I do agree that beliefs, etc. help to order regularities of behavior,
but it does prove that they have any degree of objectivity - flogiston
also ordered regularities in certain physical phenomena.
You probably know the story of neutrino - it was postualted to save
the principle of conservation of energy in case of beta decay. As such
it was of course not an explanation at all. However, later it was found
that such same particle shows up in many other elementary particle and
nuclear phenomena. Only then could it be accepted as a 'real' particle and
not a fiction invented by someone who did not want to accept that energy
conseravtion can be violated.
...........
>
>>Now I am sure that one can construct a robot powered by batteries, which it 
>>from time to time has to recharge from an electrical outlet in the lab walls.
>>Assume also that the robot memorizes the position of the outlet when it 
>>wanders around the lab in its 'free' time. Now you could of course say 
>>that the robot 'believes' that there is electrical current in the outlet,
>>since every time its batteries are low it would go to the outlet. In case of
>>robot this is not necessary, since we know well how its system works and can
>>explain its behavior without invoking  the 'belief'.
>
>I don't have any problem with the idea that a robot has
>beliefs. However, the whole point of ascribing beliefs and desires is
>that it provides a very compact way to both explain past behavior and
>predict future behavior (in novel contexts). If the folk psychology
>explanation of the behavior simply restates the behavior, then it is
>not worth much.
>
OK, if you do not have problems with robot's "beliefs" then we have less 
disagreement that I've thought. However, I think that most proponents of
beliefs, desires etc, would protest.
Yes, there are regularities in behavior and correlations between various
behaviors, and beliefs etc. do have a role in a 'folk' context, but
perhaps not in a scientific context.
...........
>As I said, I don't think that a better, or even a "complete"
>understanding of the way the brain works would supplant an explanation
>of behavior in terms of desires, beliefs, etc. A psychological
>explanation---"The man shot the raccoon because he was angry that it
>had knocked over his trash can."---is a much *better* explanation
>than one that goes "The man shot the raccoon because such and such a
>neuron fired..." even assuming that the second explanation is
>possible. It is better because it is succinct and doesn't get bogged
>down in irrelevant details.
>
Flogiston also explained certain phenomena to some extent.

>Daryl McCullough
>ORA Corp.
>Ithaca, NY

Andrzej
-- 
Andrzej Pindor                        The foolish reject what they see and 
University of Toronto                 not what they think; the wise reject
Instructional and Research Computing  what they think and not what they see.
pindor@gpu.utcc.utoronto.ca                           Huang Po
