SUO: RE: Question about Example in KR Book
John:
Yes, it's only fair that if we can have the "naive realist", we should also
have the "naive nominalist" (or, in your terms, the "extreme" nominalist).
Actually, it seems to me that your points are directed more at Hume's
critique of causality (the "problem of induction") than at nominalism. i.e.
what warrants our assumption that observed regularities will continue, in
the future, to be regularities? Aren't causal laws just a more respectable
form of the gambler's fallacy?
It's been many years since I've read the relevant literature. But my own
answer would be that science is the process of sorting out those
regularities we can rely on (and for which we formulate causal laws) from
those we can't. A pragmatic view of science, if you will.
Realism/nominalism might enter the picture, at this point, in the following
way: what distinguishes the reliable from the unreliable regularities? The
realist would say: the reliable ones reflect Nature as it really is. A
correspondence theory of the truth of causal laws.
The nominalist would say: the reliable ones do not stand alone. They are
part of vast systems of laws -- physics, chemistry, biology, neuro-sciences,
etc. -- which "hang together", which form a consistent system of laws. No
newly proposed law would be accepted as worthy of scientific investigation
if it contradicted the established body of laws (except in Kuhnian periods
of "revolutionary science"). A coherence theory of the truth of causal laws.
After the nominalist's reply, however, Hume's problem of induction, of
course, still applies. It just applies on a larger scale. Hume would ask why
we believe that the vast pattern of regularities covered by all the causal
laws in all the branches of science will continue in their regular patterns
tomorrow?
The realist would answer Hume thusly: "because those laws describe reality
as it really is". Rorty (our favorite "agree to disagree" philosopher) would
say that that answer is an empty compliment paid to our favorite beliefs. It
is empty because we cannot stand outside the interpretation of what we
experience (of which a belief in those laws is a fundamental part), and
compare that interpretation to the reality it interprets.
The "extreme" nominalist would answer Hume thusly: "because the system
consisting of those laws and of the experience-reporting statements we make
when we test them, seems internally consistent". And the
nominalist/pragmatist (i.e. Rorty) would add: "also because belief in the
knit-together system of causal laws that is science has thus far enabled us
to gain an immense control over the physical world around us". (The
ultra-sophisticated nominalist would change "enabled us" to "seems to have
enabled us", to avoid sneaking enough realism in as to threaten
inconsistency.)
As I said before, my view is that the central problem of epistemology and
metaphysics today (IMHO, not a generally bandied about opinion) is to get a
new understanding of realism that the "can't stand outside and compare
concepts to reality" criticism does not apply to, and a new understanding of
nominalism that the "shouldn't drive a car" criticism does not apply to.
Maybe the labels "realism" and "nominalism" get dropped, in the process of
forging this new understanding. But, regardless, I don't think we (all of
us) are there yet. For example, I think that your four-point elaboration,
below, does not get you beyond your admittedly oversimplified soundbite. I
think it does not get you beyond the "naive realist" position of language as
a picture of reality, and thus does not get you beyond the "can't stand
outside and compare concepts to reality" objection to that form of realism.
It's just more of the (polite, academic) Johnsonian table-thumping that most
of Rorty's opponents engage in. Thumping tables does not make the case for
realism. You realist guys will have to do better than that. (Have the
nominalists done any better, though? Well, yes. I think that Rorty's
pragmatic nominalism, as adumbrated above, is a step beyond extreme
nominalism. I also think that there are still miles to go (oh, oh. That one
doesn't end up where I wanted it to!) I also think that there is still a lot
of work to do.
All this is, however, a far distance from anything that makes a difference
to constructing a SUO. And so probably I was inappropriately heavy-handed in
taking you to task for your soundbite. However, you and I have had some
exchanges I have found interesting (hope you have, too), and maybe that's
justification enough for these comments.
Tom
-----Original Message-----
From: John F. Sowa [mailto:sowa@bestweb.net]
Sent: Saturday, November 22, 2003 1:34 AM
To: Tom Johnston
Cc: cg@cs.uah.edu; SUO
Subject: Re: Question about Example in KR Book
Tom,
I'll admit that my brief soundbite was oversimplified.
But I believe that the basic principle is sound:
1. Anyone who pretends that the laws of physics are merely
summaries of past observations, as some self-proclaimed
nominalists have claimed, is a hypocrite unless he or
she behaves according to those principles in everyday
life.
2. Anyone who is willing to trust his or her life to
something that is constructed under the assumption
that the laws of physics are reliable must believe,
at the only level that really counts, that there is
something real that supports those laws.
3. Therefore, anybody who drives a car must believe that
the laws of physics, as they have been proposed by
Newton and others and as they have been used by
automotive engineers, describe something that is
"really real".
4. And a person who is willing to admit that the laws
of physics are real and dependable guides to what
happens in reality cannot be considered a strict
nominalist.
I admit that there are as many different shades of
philosophical positions as there are philosophers, but
I stand by the point that nobody who drives a car can
consistently maintain an exrreme nominalism that denies
the reality of physical laws.
And I would claim that anybody who admits the reality
of at least some physical laws is more than 50% along
the way toward being a realist. The actual percentage
depends on which of various kinds of laws and other
scientific constructs one is willing to admit as "real".
John