In "The
Compatibility
of Naturalism and Scientific Realism" (Dec. 2003) , Brian Holtz
offers
two objections to my argument in "The
Incompatibility of Naturalism and
Scientific Realism" (in Naturalism: A Critical Appraisal, edited by William Lane Craig and J. P.
Moreland, Routledge, 2000). His responses are:
(1) my argument can be deflected by adopting a pragmatic or empiricist
"definition" of "truth", and (2) the extra-spatiotemporal cause of the
simplicity of the laws need not be God, or any other personal being.
In both cases, Holtz simply misconstrues my argument.
(1) is an imprecise rendering of my
central response, which remains:
As can be seen below, Koons'
response seems not to engage my argument that he "mistakes
a definitional (or methodoligcal) connection for a
causal connection" and that he "assumes we can
make parsimony-independent empirical tests for
correspondence-truth and then reach the amazing empirical discovery
that the true theories always turn out to be the (ceteris paribus) most
parsimonious ones. [..] Koons simply does not
address the position that simplicity is inseparable from the notion of
truth in an irreducible and a prioristic way."
Koons' response makes only one glancing reference to my central
argument:
The bulk of my paper was an attempt
to demonstrate that Koons' argument depends on the role of simplicity
not being "methodological" or "definitional", and in his response all
he says on the topic is that we agree that simplicity is
"indispensible". This remark simply doesn't address my point: if
simplicity is built into the notion of truth, then the simplicity of
true laws is not an effect needing a cause -- supernatural or
otherwise. My counter-argument is thus that the parsimoniousness of
true laws
is as much an "effect" as the unmarriedness of bachelors, and that
Koons' search for a "cause" here is a category mistake. It would be
interesting to
know what Koons thinks of this counter-argument, but his response gives
no clue.
I don't see in Koons' paper a demonstration that
scientific realism (as he defines it) is incompatible with the idea
that simplicity is built into the proper notion of truth. He quotes
Forster and Sober as saying that "viewing simplicity as an irreducible
and a prioristic sign of truth" is a "price" for accepting
scientific realism, a price paid by "eschew[ing] empiricism". But no
explanation is given of what it means to "eschew empiricism"
here. If empiricism is the thesis that all synthetic propositions
can only be known from experience, then there is no inconsistency
between empiricism and "viewing simplicity as an irreducible and a
prioristic sign of truth". (If the empiricism in question here is just
the narrow one saying that our criteria for truth constitute an
empirical discovery, then the "price" here is just a restatement of
what we've bought.)
I define "naturalism"
in such a way
that the existence of any extra-spatiotemporal cause, whether personal
or not, is inconsistent with it. The word
"naturalism" has a large number of possible definitions -- I fastened
on one that occurs quite frequently in the philosophical literature (my
definition coincides exactly with David M. Armstrong's).
It's my argument -- I get to stipulate what I mean by
"naturalism" in the context of my paper.
As I said: "I agree with Koons that naturalism is
the assertion of causal closure, and my disagreement with his
characterization of that closure as spatiotemporal is independent of my
disagreement with his paper's overall argument. His argument, and my
response, is the same for either notion of naturalism." I have a
special interest in the problem of defining supernaturality,
and the fact that Koons doesn't here defend his definition from my
criticisms of it indeed does not mean that his overall incompatibility
argument has been dented. They are separate debates.
I think Holtz goes
wrong by supposing that my
paper is supposed to be an argument for God's existence, or for the
existence of an extra-cosmic designer.
I indeed think that when the causal non-closure
Koons seeks to demonstrate is properly analyzed, it turns out to be not
spatiotemporal but intentional and thus susceptible to linking with the
intentionality of a designer. But on Koons' spatio-temporal
definition of naturalism, it's true that he's only arguing for an
extra-cosmic source of simplicity, about which he says nothing more.
Such an objection can be demolished without construing the
simplicity of truth to be an empirical discovery. There are indeed some
atheists who have tried to argue that the Big Bang is evidence for an
uncaused beginning of the universe, and their arguments are indeed
weak. In my judgment, the proper response is to focus not on cause but
on explanation, e.g. as Nozick does.
Now, to be fair, there
is one part of my argument,
a subsidiary part, that Holtz does engage: my claim that if one is a
scientific anti-realist (as Holtz is), then one cannot plausibly appeal
to the authority/prestige of science to settle any ontological or
metaphysical question (such as the existence of God or human souls). Holtz clearly thinks I'm wrong about this, but
I find his argument (if there is one) exceedingly hard
to follow.
Koons seems to have my paper
confused
with someone else's. My paper does not mention gods or souls.
Also, I don't consider myself a scientific anti-realist. As far
as I can tell, the philosophical debate over scientific realism is
plagued by the fallacy of the excluded middle, due mainly to the
mistaken notion that there is some sharp and principled distinction
between observables and non-observables.
Perhaps this is what's going on: Holtz thinks that there is no such thing as objective reality, and reality that doesn't depend on human practices and preferences (in particular, those a priori preferences that constitute a large part of our theoretical practices). So, science tells us all there is to know about the only "reality" there is.
I do in fact think there is an objective reality,
but I also think we lack apodictic certainty in our observations of it.
In other words, I believe there is a some defensible middle ground
between radical subjectivism and radical realism.
If this is Holtz's
view, there are two huge
problems with it -- problems that should, I think, persuade any
naturalist worth his or her salt that this is not the path to take. First, there are the powerful arguments
developed by the Polish logician Tarski against any pragmatic
"definition" of truth. (1) For any sentence S, such as 'snow is white',
it is a truism that 'S' is true if and only if S (e.g., 'snow is white'
is true if and only if snow is white). (2)
It is logically possible that snow is white, even though it is not
useful to believe something expressible by 'snow is white'. (3) Hence, if 'is true' is logically
equivalent to 'expresses something it is useful to believe', then it is
logically possible that snow is white even though 'snow is white' is
_not_ true. (4) Hence, if a pragmatic definition of truth were correct,
it would be logically possible for snow to be white and not to be white
(at the same time and in the same way). Contradiction.
(5) Therefore, pragmatic definitions of truth are incorrect.
If immediate utility
were the way we decided whether individual theories were true, then we
might declare true the most baroque or even contradictory theories in
an orgy of convenient cognitive dissonance. The criterion of utility in
(H) is employed at a more fundamental level, at which we are choosing
the fixed truth criterion to apply uniformly to all theories. It might be useful
for me to believe particular theses such as I am handsome or funny or
well-liked, but I should not do so if I believe at a more fundamental level in the
utility of e.g. only adopting beliefs that are parsimoniously
consistent with available evidence.
Thus, I don't say "snow is white" is true simply
because it is useful to believe that snow is white. Rather, I say it's
true because I'm led to that conclusion by my unvarying policy for
deciding whether statements are true, and it is this unvarying policy
-- not any particular ad hoc truths -- that I adopt for pragmatic
reasons.
Holtz will, I assume,
want to deny (2), but it is
easy to imagine scenarios in which some fact holds, even though it is,
all things considered, more useful to believe a sentence expresses the
denial of that fact.
What I deny is that it is more useful to an adopt
an alternative truth-deciding policy over the usual policy based on
parsimonious empirical rationality. However, I can
imagine possible worlds in which (for example) gods arrange things so
that a policy of revelation-based truth-deciding turns out to be more
useful than parsimonious empirical rationality. Luckily, we appear not
to live
in such a world.
Koons' dilemma here seems to suffer
from an excluded middle. It's not the case that either 1) the
precise semantics of our linguistic constructions must be reducible to
"truisms" that are "obvious to any competent user of English", or 2)
those constructions embed
empirical discoveries about this universe. For example, 'the
present king of France' is a phrase that can be processed by any
competent user of English, and yet Bertrand Russell was not doing
empirical science when he sharpened our understanding of such phrases
with his theory of Definite Descriptions. Similarly, one could
argue that Hilary Putnam added to our understanding of the semantics of
the word "water", again without empirical investigation of his Twin
Earth. So I don't think it's a stretch to say that a speaker of English
can competently process any workaday use of the word 'truth' without
necessarily having a fully-developed philosophical theory of truth.
I just don't agree with
Koons there is some "essence of truth" about which we can make
empirical discoveries (such as the alleged
discovery that Truth tends toward beauty or simplicity). I indeed
claim that choosing one's truth criterion is ultimately a matter of
empirical pragmatism, even though once it's chosen that criterion (and
not pragmatism) is how one decides the truth-value of all particular
propositions. And as I
said
before:
The "real world" indeed tends to reward one for choosing a worldivew based on parsimonious consistency with evidence (i.e. truth), and tends to punish one for choosing otherwise. This arrangement is not a coincidence, but it does not suggest a supernatural arranger. Rather, it is entirely to be expected that there be a best practice for thinkers to adopt in thinking about the world and that thinkers under selective pressure tend to adopt that practice.
Koons summarizes:
I'm not sure whether Koons here is asserting that there exists a "real essence of truth", or just that his hypothetical pragmatist would have to posit one. I see no reason to posit such a platonic essence. The closest I would come is to remark (as I did) that reality "tends to reward one for choosing a worldivew based on parsimonious consistency with evidence (i.e. truth), and tends to punish one for choosing otherwise."
The second critical
problem with Holtz's position is that he gives us no reason for
accepting his particular version of the pragmatic definition of truth
(one that incorporates scientific standards of parsimony) over any of
the myriad of alternatives.
My critique of Koons' argument requires no
"particular version of the pragmatic definition of truth" -- it merely
requires a recognition that explanatory economy is built into any
sensible notion of truth. To deflect my objection, Koons would have to
show that no sensible notion of truth can involve explanatory economy
in its definition. I presented an extended argument for my position,
but Koons makes no direct argument against it.
Koons' phrase "scientific standards of parsimony" suggests a
misunderstanding of my position. Nowhere in my paper do I say
that explanatory economy
necessarily involves scientific standards. My position is
that explanatory economy is inherent in our notion of truth even
outside scientific specialties, and that good science depends on good
epistemology, rather than the other way around.
-- but where's
the psychological and
sociological evidence for that claim?
Rather than plead guilty to scientism, I'll say
again that valid epistemology is the foundation for valid
science, rather than the other way around. (Note the irony of Koons
invoking psychology and sociology in the prosecution of scientism.)
I never said that anyone's goals count more than
anyone else's. For example, if Jane's goals don't include
avoiding
car accidents, then she is free to ignore what I would call the truths
of optics in her use of her car's mirrors while changing lanes.
Each person need only care about her own goals, not mine or those of my
pals. My reference to utility and goals was intended not to claim that
there are preferred or objective standards of utility, but in fact to
short-circuit the potential objection that my theory of truth depends
on some particular standard of utility. Rather, my theory applies to
anyone who has any utility function whatsoever.
The
naturalistic pragmatist will quickly find himself mired in a morass of
relativism.
One needn't seek refuge in complete and absolute
objectivity in order to steer clear of absolute relativism. The
regularities of this universe provide a reliable way of testing one's
epistemology (including one's truth criterion), and we are provided (if
not mandated) a set of default goals derived from our nature as
intelligent social mammals in a universe subject to the second law of
thermodynamics. People can exchange those goals for others (perhaps at
their own risk), but their actions will inevitably reveal what goals --
and what truth criterion -- they have chosen.