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TRUTH, REFERENCE, AND REALISM:PUTNAM’S CHALLENGE
Abstract
The question of truth is perhaps a perennial question of philosophy. Is truth “merely” epistemological, a function of contingent human practices and
conventions, or should we adopt a stonger, metaphysical conception of truth along realist lines, understood as correspondence with objectively existing reality? In this
paper I examine a famous debate in the analytic philosophy of language that hinges on the status of truth – specifically, the challenge to traditional or
metaphysical realism posed by Hilary Putnam’s model-theoretic argument and the “paradox” that David Lewis derived from it. In the end, I will argue that
metaphysical realism is a theoretically excessive position with regards to truth, and that a pragmatic or epistemological understanding of realism is, in Putnam’s
words, “all the realism we want or need.”
Table of ContentsI. Introduction………………………………………………………………p. 2 II. The Model-Theoretic Argument………………………………………..p. 8III. Putnam’s Paradox and Lewis’s Metaphysical Realist
Solution……….p. 11IV. Catherine Elgin’s Pragmatic Objections to the Lewisian
Solution…...p. 20V. Putnamian Internal Realism…………………………………………….p. 27VI. Conclusion………………………………………………………………..p. 36VII. Bibliography……………………………………………………………...p. 39
Allen Porter | 2
I. Introduction
What is truth?
It may seem hubristically over-ambitious to begin a contemporary
philosophy paper with a question of such seemingly fundamental and wide-ranging
scope – why not simply take on the question of the meaning of existence, while
we’re at it? In actuality, however, the former question is not necessarily so
daunting as it might initially seem to be, given the context of contemporary
analytic philosophy. For the question of truth has a storied history and indeed a
central place in the analytic tradition, which has developed tools to render it a
more tractable problem – tools, in particular, which makes it possible for us to “get
ahold of” and articulate this problem in a determinate way.
1 Specifically, since the work of the famous Polish logician Alfred Tarski (so
essentially for eight decades now), philosophy has possessed a semantic definition
of truth in the form of a definition of truth for formal (mathematical, logical)
languages, i.e. the criteria for a sentence of a formal language to count as true.
This semantic definition was not necessarily intended to compete with stronger or
more “full-blooded” conceptions of truth2, but the confrontation is nevertheless
1 N.B.: With the aim of facilitating the flow of reading, I have bolded footnotes which contain substantive commentary and are meant to be read when encountered in the text, as opposed to mere textual citations. 2 Tarski was essentially just not interested in this problem; his sentiments in this regard are later echoed by Davidson in his “Truth and Meaning” 24: “But my defence [of Tarski’s semantical concept of truth] is only distantly related, if at all, to the question whether the concept Tarski has shown how to define is the (or a) philosophically interesting conception of truth, or the question whether Tarski has cast any light on the ordinary usage of such words as ‘true’ and ‘truth’.” Davidson then laments the “futile and confused battles over
Allen Porter | 3
inevitable: could the “merely semantic” conception of truth in fact be all there is to
the notion (or all we need from it)? Ought we to perhaps be deflationary with
regard to truth? But deflationary relative to what – what is the “more” of this
notion that gives it the aura of the ineffable, the flavor of sacred metaphysical
mystery? That is, if the semantic conception is deflationary, what is the grander
notion of truth that is not – the notion that, in ordinary discourse, is on a par with
terms like “Being” and “The Good”?
Analytic philosophy also affords us the resources for a precise
characterization of even this “grander notion”: namely, in terms of the
metaphysical position of realism. Metaphysical realism asserts that truth is
objective, or perspective-independent (which I mean to be a notion broader than,
as well as inclusive of, that of “mind-independence”): truth, in other words, is or is
correspondence with the way the world really, objectively is. A metaphysical
realist, then, would take the notion of truth-relative-to-a-language (or the semantic
definition of truth) to be derivative of the more primary or fundamental
metaphysical notion of truth as the way reality is – so that a true sentence of some
language is true in virtue of the world objectively being the way the sentence says
that it is. On this view, in other words, truth is not or at least not ultimately
determined intra-linguistically or “by us”, i.e. by the rules we construct for
determining whether to count a sentence as true in some formal language, but
rather extra-linguistically: our language and our linguistic rules should aim to
accurately reflect external, objective reality, and the ultimate criterion for a
sentence’s being true in any language is the extra-linguistic, realist one of
these questions”, just as Tarski considered “[d]isputes of this type” to be “always meaningless, and therefore in vain” (“The Semantic Conception of Truth and the Foundations of Semantics” II.14). For the sake of this paper, I hope these sentiments are off-the-mark.
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according with or corresponding to objective reality – for the metaphysical realist,
truth is thus emphatically not just semantic truth. 3
The attentive reader will note that in the preceding paragraph, I took care to
qualify realism as “metaphysical realism”. This might seem redundant, in that
realism is perhaps the metaphysical position par excellence, more paradigmatic
even than that famous couple, materialism and idealism; but in point of fact, there
is more than one understanding of realism, a point that turns out to be crucial for
the question before us, namely that of truth.
Specifically, in his 1977 “Realism and Reason” and elsewhere, Hilary
Putnam both posed a challenge, hinging on the notion of truth, for metaphysical
realism (as described above) and proposed a new form or understanding of realism
as a solution, which latter he named “internal realism”. I think perhaps the best
way to characterize the latter, in contrast to the former, is as epistemological
realism; but before introducing Putnam’s proposed version of realism, which could
equally aptly be termed “pragmatic” as “internal” or “epistemological”, a more
precise explication of the incumbent it challenged and the dialectic it provoked is
in order.
Let me offer a more formal characterization of metaphysical realism. In
terms of reference, a metaphysical realist would take the fact that, e.g., pigs are
included in the extension of the predicate “are animals” but not in that of “are
winged animals” to reflect an objectively true or perspective-independent feature 3 Positions on truth and reference that assert that “The truth of a sentence consists in its agreement with (or correspondence to) reality” (Tarski 343) are often labeled “correspondence theories”. For instance, the “picture theory” of the early Wittgenstein of the Tractatus – in which atomic referential units or names directly correspond to metaphysical simples in the world, and in which complex referring constructions are truth-functionally constituted from these linguistic simples and correspond to arrangements of metaphysical simples or “states of affairs” – is an early example of this. (Notably, while this paper is critical of such realist views, the pragmatic alternative it favors can largely be sourced back to the later Wittgenstein, of the Philosophical Investigations and e.g. On Certainty.)
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or fact of reality (namely, that pigs don’t have wings, whatever one may think
about this fact: perhaps, e.g., one has taken a psychedelic and consequently
hallucinates a flying pig – this would not change the fact that flying pigs do not
exist). In other words, for the metaphysical realist the criterion for truth-in-a-
language would be correspondence with the objective truth of reality – the
Tarskian semantic definition would describe how our language must be structured
to represent truth, but that truth would be independent of and prior to that
definition.
Contrast this with the view that takes the semantic conception of truth to be
an alternative to, rather than a working part of, metaphysical realism. The
semantic conception of truth relative to a formal language is defined in terms of so-
called “satisfaction relations”4 as follows. Assume we have a formula F in some
object language, such that F contains at least one free variable (e.g., the formula
could be “x is a pig”, where of course x is the lone free variable and the object
language is English), and assume that we have an interpretation, A, of the formula
(i.e., an assignment of referents to the free variables in F, or in other words, a
fixation of F’s reference). Then the interpretation A is said to satisfy the formula F
iff the sentence (i.e., interpreted formula) F comes out true under the assignment
of referents according to A – so that, e.g., if the formula is “x is a pig”, and if A
assigns a pig (say, demonstratively: “this pig”) as the referent of x, then we can say
that A satisfies the formula because the sentence “this pig is a pig” is true. If, on
the other hand, interpretation A assigned an airplane as the referent for the free
variable in F, it would not satisfy the formula, since “an airplane is a pig” is a false
sentence.
4 Putnam, “Realism and Reason” 483
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Now, as I have presented it, this may seem more like a definition of
satisfaction relations in terms of the prior notion of truth, rather than vice-versa –
it may seem as though I have tried to circularly define truth in terms of the
satisfaction relation, and this in turn in terms of true sentences. But the sense of
the word “true” in “true sentences” here is a specific one, and one that, in
particular, can be paraphrased in a way that eliminates the notion of truth. That is,
what does it mean to say that an interpretation satisfies a formula if the sentences
of the interpreted formula are true or “come out true” (sometimes “come out right”
is used, presumably in order to avoid this very confusion)? Well, it is not an
allusion to the metaphysical realist conception of truth as correspondence with
objective reality – rather, in this context, for a sentence to “come out true” under
an interpretation is for it to accord with the intentions of the speakers of the
language (as opposed to, e.g., according with the way the world really is).
For instance, let’s say the language in question is English. Does a pig satisfy
“x is an animal” – does an interpretation that assigns some pig as referent to this
formula result in a true sentence? Well, it depends – do we want it to, or more
perspicuously, do we mean it to? Do we want a pig to count as an animal? Is that
how we understand the term “pig”, or if it is a new word we are coining, is that
how we want the term to be understood in the future? In other words, it depends
upon what we intend to mean by the words figuring in the sentence, here “pig” and
“animal” (also, technically, “is”); for example, if we were to intend “pig” to refer to
airplanes rather than to pigs, then a pig would not satisfy the formula, because we
intend for “pig” to refer to those large mechanical vehicles of transportation that
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fly in the sky – and if those are what “pigs” are, then it is false that “a pig is an
animal” (it would instead be a machine).5 6
And this is the crucial point vis-à-vis metaphysical realism and a “stronger”
conception of truth: if semantic truth or truth relative to a(n interpreted) language
is only constrained by the desideratum that true sentences accord with intended
meanings, then why not think that this is, in fact, all there is to truth – in other
words, that truth is ultimately “up to us”, that truth is more a descriptive notion of
how we use language to refer to the world and its entities than a normative and
theory-independent goal to be achieved? That is, if we understand truth as just
semantic truth, in terms of what assignments of referents match up with our
intentions (i.e., in terms of what assignments result in sentences that accord with
5 I have really given the concept rather than the definition here, strictly speaking, as the technical details of the latter exceed the scope and purpose of this paper. The idea in more detail, but still informally, is that an adequate definition of truth should logically entail all instances of Tarski’s “Schema T”: “X is true if and only if p”, where “X” is replaced by a name for a sentence and “p” by that very sentence. This schema is in fact a formal generalization of the definition of a true sentence on the basis of satisfaction relations, as presented above – so that, e.g., if a pig satisfies “x is an animal”, then the fact that “a pig is an animal” is a true sentence because it accords with our intended meanings can be captured by the schema: “ ‘A pig is an animal’ is true if and only if a pig is an animal.” So again, is a pig an animal? Again, it depends on what we intend to mean by these words. Note, however, that Schema T is not the definition, it is rather a criterion of adequacy: the definition must entail all instances of the schema – in other words, all an interpreted language’s satisfaction relations taken together would constitute “a complete specification of the semantical conception of truth” (A Companion to Analytic Philosophy p. 125).6 A clarification: instances of the semantic definition are purely formal, in that Tarski “required his definitions to be free of undefined semantic notions (such as reference and application) [and] to be constructible from notions already expressible in the object-language” (Soames, Philosophy of Language 39). Because truth is here just semantic satisfaction, one can know what such an instance expresses without knowing its meaning, so that Soames can say “Thus, statements of Tarski-truth conditions provide no information about the meanings of sentences” (ibid.). But this should not be misunderstood: a given Tarskian satisfaction relation tells us nothing about the meanings of the words, but – and this is the point pertinent to my purposes – it is still dependent on or responsive to intentions in the way described above; even in the original mathematical case, where satisfaction is purely formally defined via axioms, the axiomatic structure itself is responsive to our intentions to capture the meaning of the logical symbols as they function in e.g. arithmetic – and with less formal languages, it is the intended meanings of the non-logical vocabulary that come to the fore / must be respected for satisfaction, as I have emphasized in the main text.
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the meanings we take or want the interpreted terms of the language to have) –
then what is wrong with this? 7
This is perhaps already challenge enough for metaphysical realism – i.e. the
possibility that the semantic definition (deflationary, relative to the realist
conception) of truth might be a viable alternative to the realist notion. But Hilary
Putnam, in “Realism and Reason”, posed an even stronger challenge to traditional
or metaphysical realism, in the form of what is now well-known as “the model-
theoretic argument”: in effect, that the semantic conception is all we need from a
concept of truth, and all we should want; for not only can it be taken as an
alternative to the metaphysical realist conception of truth, but it in fact does all the
philosophical work that we might want the stronger notion to do, so that we stand
to lose nothing by abandoning the latter – and, further, it turns out that there is no
way to differentiate the stronger notion from the semantic one in any given case
aside from the putative applicability of the metaphysical and wholly unverifiable
demand that truth correspond to objective reality (which, if it does no work, seems
theoretically excessive and untenable). And so Putnam proposed, as a solution to
his own challenge, a new, pragmatic understanding of realism that he named
“internal”.
But some realists were dissatisfied with Putnam’s solution, which I will
present and defend in section V. Most famously and influentially, David Lewis 7 Again, the argument is not that the semantic conception of truth is incompatible with a metaphysical realist conception. The point is rather that the former does not entail the latter – it defines truth in terms of semantic satisfaction without any non-eliminable reference to the notion of truth. And it is this fact that raises the question of whether – compatible or not – the semantic conception might work just as well as a stronger notion, i.e. could serve as an alternative to without being incompatible with a stronger conception; and this question, if answerable in the affirmative, then raises the further issue of what advantages a stronger conception would have that the semantic alternative does not – in other words, the question of what we would stand to lose by settling for the semantic conception. And Putnam’s answer to this, finally, will constitute the challenge; namely: “nothing” – a metaphysical realist notion of truth does no work not doable by the “merely” semantic conception.
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characterized the model-theoretic argument’s challenge as “a bomb that threatens
to devastate the realist philosophy we know and love”, and its author as one who
“has learned to stop worrying and love the bomb” and who “welcomes the new
order that it would bring”8 – whereas Lewis, on the other hand, cannot bring
himself to accept this solution, which involves the abandonment of the familiar and
beloved metaphysical realism.
In fact, Lewis’s seminal 1984 paper “Putnam’s Paradox” is the chief textual
touchstone for the literature on this issue – even perhaps to the point of eclipsing
Putnam’s own original formulations in “Realism and Reason” and “Models and
Reality”. And since the name “Putnam’s Paradox” is due to Lewis’s titular paper, I
think it appropriate to distinguish the “paradox” so-called from the strictly
narrower model-theoretic argument; hence, I will take the paradox to refer to the
understanding or interpretation of the model-theoretic argument provided by
Lewis, which strictly speaking expands the latter by framing its conclusion
specifically in terms of the descriptivist theory of reference. That is, where the
model-theoretic argument poses a challenge to metaphysical realism, the paradox
frames this challenge as the dilemma of an apparent incompatibility of
metaphysical realism with descriptivism as a theory of reference. In both cases,
however, at stake is the question of truth – in essence, whether we should
understood truth metaphysically or epistemologically (pragmatically).
In what follows, I will examine what I take to be the most significant
contributions to the literature on this topic. Specifically, after presenting the
model-theoretic argument and paradox in more detail, I will evaluate
(1) David Lewis’s proposed realist solution
8 Lewis, “Putnam’s Paradox” 221
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(2) Catherine Elgin’s “evolutionary adaptation” objection to Lewis’s solution in
“Unnatural Science”
(3) Putnam’s own solution of internal realism
And I will ultimately side with Elgin and Putnam, arguing that an
epistemological or pragmatic realism is “all the realism we […] need”9.
II. The Model-Theoretic Argument
Let me informally summarize the argument and how the paradox frames it.
The challenge, in broad strokes, is the claim that: for any language (comprising
syntax, logical vocabulary, and non-logical vocabulary, the last being composed of
singular referring terms or names and general referring terms or predicates) with
an infinite stock of referential terms, and given an infinite stock of referents in the
world, there will always be more than one model (an assignment of referents to
referential terms – what I referred to as an “interpretation” when explaining
Tarskian satisfaction above) of the language such that each model is internally
consistent but logically incompatible with the other models.
And the upshot of the argument is that – if truth is just truth-in-a-model,
truth relative only to the constraints internal to the model (i.e., as above, the chief
such constraint being that of sentences having to “come out right” in accord with
speakers’ intentions) – then there is no in-principle way to distinguish these models
in terms of the realist criterion of (objective or model-independent) truth; no way
to say that some one model, e.g. our own or actual one, is the right one, in virtue of
truly reflecting or “capturing” the structure of reality.
9 Putnam, “Realism and Reason” 489
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And as we will see, the reason that, with Lewis, this challenge takes the
form of a forced choice between metaphysical realism and the descriptivist theory
of reference, is that if descriptivism is the right theory of reference, then any
constraints responsive to our intentions can be framed descriptively, so that the
problem becomes that the constraints internal to descriptivist theory seem
insufficient to fix reference in a determinate way. Hence, it would appear, either
metaphysical realism is false or descriptivism is false as the theory of reference –
either reference cannot be determinately fixed, or descriptivism is an inadequate
theory of reference because it cannot account for the determinate fixation of
reference.
Now, despite the name, the argument only really requires a little bit of
“model theory in its ‘basic form’”10 11, and really just what is required for the
premise that any world can satisfy any theory (in the sense of “satisfaction”
explored above), given that the theory is consistent and has a large enough stock
of referring terms, and given that its domain (i.e. the objects in the world, or the
world’s collection of potential referents, which we can safely assume to be infinite)
is large enough. As Lewis says: “A consistent theory is, by definition, one satisfied
by some model; an isomorphic image of a model satisfies the same theories as the
original model; to provide the makings for an isomorphic image of any given
model, a domain need only be large enough.” (I will elaborate the significance of
this last clause shortly.)
10 Lewis, “Putnam’s Paradox” 22211 In “Models and Reality”, Putnam characterizes the model-theoretic argument as an extension of the so-called “Löwenheim-Skolem Paradox” in formal logic (“so-called” because it is not generally taken to constitute a real antinomy in formal logic) to the philosophy of language (where Putnam thinks it does become a genuine antinomy, “or something close to it”). But as David Lewis notes, “The premise that joins with global descriptivism to yield disaster is not any big theorem of model theory. In particular, it is not the theorem that gets star billing in M&R, the Skolem-Löwenheim Theorem.” (ibid. 229)
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And again, this “indeterminacy” (i.e. metaphysical if not epistemological
indeterminacy) of reference would be a “disaster”12 for metaphysical realism,
since, as Putnam says: “The most important consequence of metaphysical realism
is that truth is supposed to be radically non-epistemic – we might be ‘brains in a
vat’ and so the theory that is ‘ideal’ from the point of view of operational utility,
inner beauty and elegance, ‘plausibility’, simplicity, ‘conservatism’, etc., might be
false. ‘Verified’ (in any operational sense) does not imply ‘true’, on the
metaphysical realist picture, even in the ideal limit.”13 I will return to the relation
between pragmatic verification and realist truth when I examine Putnamian
pragmatic realism; for now, the important point is that the model-theoretic
argument tells against this possibility, namely that an empirically ideal (consistent,
simple, “as verified as can be”14, etc.) theory might nevertheless be false, in virtue
of the world not being the way the theory says it is – i.e., that there might be more
to truth than what is captured in the semantic conception.
Here is how Putnam somewhat more formally presents the argument in
“Realism and Reason”:
So let T1 be an ideal theory, by our lights. Lifting restrictions on our actual all-too-finite powers, we can imagine T1 to have every property except objective truth – which is left open – that we like. E.g., T1 can be imagined complete, consistent, to predict correctly all observation sentences (as far as we can tell), to meet whatever “operational constraints” there are (if these are “fuzzy”, let T1 seem to clearly meet them), to be “beautiful”, “simple”, “plausible”, etc. The supposition under consideration is that T1 might be all this and still be (in reality) false.
I assume THE WORLD has (or can be broken into) infinitely many pieces. I also assume T1 says there are infinitely many things (so in this respect T1 is “objectively right” about THE WORLD). Now T1 is consistent (by hypothesis) and has (only) infinite models. So by the completeness theorem (in its model theoretic form), T1 has a model of every infinite cardinality. Pick a model M of the same cardinality as THE WORLD. Map the individuals of M one-to-one into the pieces of THE WORLD, and use the mapping to define the relations of M directly in THE WORLD. The result is a satisfaction relation SAT – a “correspondence” between the terms of L and sets of
12 Ibid. 22613 Putnam, “Realism and Reason” 48514 Lewis, “Putnam’s Paradox” 221
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pieces of THE WORLD – such that the theory T1 comes out true – true of THE WORLD – provided we just interpret ‘true’ as TRUE(SAT). So what becomes of the claim that even the ideal theory T1 might really be false?15
The argument essentially hinges on the fact that theoretical truth, defined in terms
of satisfaction in the Tarskian sense (truth “relative to a language”, relative to an
interpretation/model), is sufficient to meet all the “operational and theoretical
constraints”16 that we might want to saddle an ideal true theory with – which
seems to leave nothing that a stronger, metaphysical realist conception of truth
could contribute. That is, an ideal theory meets all operational constraints – e.g., it
is as “empirically verified as can be”, its sentences come out right in accordance
with the intended meanings of the terms, for instance observation sentences like “I
see a table in front of me” (so that the sentence only comes out true if I do in fact
see the table) – as well as all theoretical constraints – e.g., an ideal theory should
be simple and non-redundant, it should be plausible, etc. As we will see in the next
section, it is essentially this feature that motivates Lewis’s choice of descriptivism
for the theory of reference, since descriptivism’s “annexing power” exhibits
precisely this capacity of incorporation.
In other words, the problem is that the ideal theory conforms to all our
intentions, intralinguistic and metalinguistic, operational and theoretical – our
intention that its sentences come out true only in the right circumstances in
accordance with our intended meanings, our intention that it be whatever we want
an ideal theory to be (simple, “elegant”, etc.), etc. So then the question is: what
becomes of the metaphysical realist claim that it could be all this, and still “really”
be false?
15 Putnam, “Realism and Reason” 484-516 Lewis, “Putnam’s Paradox” 224; also cf. Putnam, “Realism and Reason” 486
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“Well”, Putnam says as he considers the logical course of the dialectic, “it
might be claimed that SAT is not the intended correspondence between L and THE
WORLD. What does intended come to here?”17
That is, the metaphysical realist might want to respond: “Well, your ideal
theory might not meet one intention – namely, the intention that the theory
correspond with objective truth. In other words, truth as semantic satisfaction
relative to the theory (to a model of the theory) might not be the intended
correspondence relation, because – even though the theory correctly predicts all
observation sentences, is simple, etc. – the world might not be the way the theory
says it is. In which case truth-in-this-model is not the truth we want/intend.” But
Putnam’s point is essentially that there is no way to characterize this desideratum
except as a pure metaphysical posit – there is objective truth, so the intended
model should correspond to it. Other than this purely principled and completely
unverifiable demand, there seem to be no intended constraints on truth that cannot
be met by truth-in-a-model, i.e. no constraint that would differentiate between
mere truth-in-a-model (of an ideal theory) and the truth-in-a-model that
corresponds to objective, metaphysical truth – that could differentiate between a
mere model and the objectively true model.
So when Putnam asks “What does intended come to here?”, he is essentially
asking “What more do you want a ‘true’ theory to be?” – a question later echoed by
Catherine Elgin in “Unnatural Science”:
The objects [that the ideal theory] assigns to the extensions of its predicates in fact belong to those extensions. Its sentences are accurate under their intended interpretations. So things are just as the theory says they are. Its predictions are borne out. The generalizations it accords the status of laws form an integrated system that subsumes events and explains why they were to be expected. How could this be considered a scientific failure? What more do you want?
17 Putnam, “Realism and Reason” 485
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Truth, replies Lewis.18
And so it is to this admirably stubborn metaphysical realist that we turn now.
III. Putnam’s Paradox and Lewis’s Metaphysical Realist Solution
In “Putnam’s Paradox”, David Lewis formulates the model-theoretic
argument’s challenge for metaphysical realism in terms of the descriptivist theory
of reference. Before explicating Lewis’s presentation of and solution to the
paradox, then, a few words on descriptivism are (finally) in order.
Broadly and in somewhat simplified fashion, the story of the descriptivist
theory of reference is as follows.
Descriptivism, the origin of which is Bertrand Russell’s seminal 1905 paper
“On Denoting”, holds that the referents of referring terms or phrases can be fixed
by means of descriptions. For instance, to the question “In virtue of what does
‘horse’ refer to horses?”, the descriptivist can reply: “In virtue of the description
that ‘horse’ means and which horses fit”. Whatever this formulaic description
might be – e.g., “‘Horse’ refers to odd-toed ungulate mammals belonging to the
taxonomic family Equidae”, or “‘Horse’ refers to animals like this one [pointing to a
horse]”, etc. – in order for it to be adequate as a reference-fixing device, it must (as
we have seen) result in true sentences (only) when the intended kind of thing
(here, a horse) is substituted for the free referential variable. So, to continue the
“horse” example, the description “‘Horse’ refers to four-legged animals that
humans use for riding and carrying things” would be inadequate, because it would
not always come out true/false in accordance with our intentions (e.g., a mule fits
this description, but we do not intend “horse” to also refer to mules).
18 Elgin, “Unnatural Science” 296
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This technique of semantic analysis proved very effective for many kinds of
reference – for instance, as we have just seen, it works very well with common
nouns or general referring terms such as “horse”, which we intuitively take to have
a certain meaning, a meaning that determines what kinds of entities should count
as referents of the referring term in question. Again, it is a question of what we
intend to mean by the term in question – if we intend “horse” to mean “an odd-toed
ungulate mammals belonging to the taxonomic family Equidae”, then mules will
not qualify as referents of “horse”. And Russell’s “theory of descriptions” also
seemed to work well for more problematic kinds of reference – including that
paradigmatic yet previously problematic case of reference, proper names.
Specifically, prior to Frege and Russell, the so-called “Millian” theory of
direct reference was dominant, according to which the meaning of a proper name
was taken just to be its “bearer”, i.e. its referent. Hence the meaning of “John
Smith” was taken to be just John Smith himself. But this inevitably led to certain
problems, such as, for example, that of negative existentials: if the meaning of a
proper name is just the bearer of the name, names with no bearers would have to
be declared meaningless – and yet while Santa Clause presumably does not exist,
“Santa Clause” does not seem to be a meaningless term. It was in part to resolve
these kinds of problems that Russell analyzed proper names as disguised
descriptions, and it was the theory of description’s widespread success in resolving
such problems that made it dominant in the theory of reference for so long.19 19 Briefly, the solution was the following. Russell proposed a rule for translating sentences with the grammatical form “a is F” into logical form. There are two possibilities: either the singular referring term “a” is a genuine “logically proper name” (which Russell thought comprised essentially just indexicals such as “this” and “that”, which directly refer to their referents), in which case the logical form will just be “Fa” – or, as in the case of “ordinary” proper names (and especially problematic singular referring terms, such as “Santa Clause”), since the logical form is “hidden” or dissembled by the grammatical form, the following translation rule must be applied to yield the description which eliminates the problematical apparent reference (left of the arrow is a schematic expression of the grammatical form of what is to be translated, right of it is the logical form into which it is
Allen Porter | 17
So descriptivism certainly has the resources to effectively fix determinate
reference in an impressive variety of cases. But what about all cases? Should
descriptivism just be one analytical tool in our theoretical arsenal among others, or
can it possibly be “the whole story” about reference? The problem with taking
descriptivism to be an adequate theory of reference, in this latter sense, is as
follows.
Given a language with a modicum of sufficiently fixed reference, we can use
that language to construct descriptions to serve as reference-fixation devices for
the introduction of new terms. For example, a detective in Victorian London
investigating a string of prostitute-murders in 1888 might say “Jack the Ripper did
x, y, and z”, even though the investigation is still in progress, and the murders
might turn out to have been committed by multiple, i.e. different, people. His
purpose with this statement, then, might plausibly be twofold: first, to hypothesize
that there exists someone who did x, y and z; and second, to stipulate that if it
turns out that there is indeed someone meeting this description, then that person
is to be the referent of “Jack the Ripper”. As Lewis says, “The intended
interpretation of the augmented language is to be an extension of the old
interpretation of the language, if such there be, that makes the new Jack-the-
to be translated):
R. Ψ [ theΦ ]⇒∃ x ∀ y¿
For instance, take the classic example “The present king of France is not bald” (of course, there is no present king of France). This is problematical because it seems to refer to something that doesn’t exist. But when the translation rule is applied, we see there are two possibilities of translation into logical form, one of which reflects the intuitive understanding of direct singular reference by entailing the existence of the individual in question, but the other of which does not. Specifically, the following translation into logical form contains no problematical reference to a non-existent entity:
“The present king of France is not bald” ⇒ ∃ x ∀ y¿
Or in English: “There does not exist exactly one thing such that that thing is the present king of France and is bald.”
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Ripper theory come true.”20 In other words, the description “the person who did x,
y, and z” fixes the reference of the new term “Jack the Ripper” on the basis of
terms that already have their reference fixed (whatever “who did x, y and z”
comprises).
Lewis terms this kind of descriptivism “local descriptivism”, and declares it
“disappointingly modest”, since while it “tells us how to get more reference if we
have some already”, this seems only to beg the question: “But where did the old
language get its reference?”21 Hence the descriptivist might be tempted to extend
this local descriptivism into a global descriptivism: fix the reference not just of
some term or cluster of terms via descriptions, but the entire non-logical or
referential vocabulary of the language – so that there is then no “old language”
whose already-fixed reference must be accounted for. And, as Lewis says, then we
“go on just as before. The intended interpretation will be the one, if such there be,
that makes the term-introducing theory come true. […] But this time, the term-
introducing theory is total theory! Call this account of reference: global
descriptivism. And it leads straight to Putnam’s incredible thesis.”22
Before explaining how global descriptivism leads straight to Putnam’s
Paradox, a distinction should be raised to preclude a potential confusion. To the
layperson, the extension from local to global descriptivism probably appears
paradoxical: if local descriptivism is the theory that introduces new terms and fixes
their reference via descriptions constructed from terms with already-fixed
reference, then how is global descriptivism even possible, i.e. how does it ever get
off the ground – would it not require some stock of terms with already-fixed
reference, i.e. those required to build the descriptions that will serve to introduce 20 Lewis, “Putnam’s Paradox” 22221 Ibid. 22222 Ibid. 222
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new terms? How it could introduce even the first new term, if it could not already
construct descriptions to fix its reference? Viewed this way, the problem seems to
be a foundationalist one of referential regress – there had to be some reference
fixed first, in order for new references to be able to get fixed; so how was this first
or original reference fixed?
But in fact this diachronic problem is not the one raised by Lewis. The global
question of the fixation of reference as treated by Putnam, Lewis, et al. is rather a
synchronic one, which is appropriate for a theoretical rather than empirical
inquiry. The question is how all of the reference of a “full” language (ideal theory)
can be consistently and determinately fixed (the synchronic aspect is captured in
the consistency requirement) – not how our actual referential scheme actually was
fixed over the course of history. In other words, the theory of reference must
account for how all of our reference “holds together” such that (e.g., on
descriptivism) all of the reference-fixing descriptions together are consistent. Or:
simply think of it in terms of the systematic fixation of the reference of all the
referential terms of the ideal theory, rather than in terms of the introduction of
these terms. That is, the question would be: given all these meaningful terms, can
they all have their reference determinately fixed descriptively?
So Putnam’s Paradox does not involve the diachronic problem that, if global
descriptivism is the correct theory of reference and thus all referential terms can
be given descriptions that fix their referents, then how were the descriptions for
the very earliest terms (the first in particular, of course) formed? In other words, it
is not the empirico-historical problem of the origin of (referential) language – it is
not e.g. Rousseau’s problem – instead, it is the theoretical problem of the
possibility of determinate reference (and hence determinate truth) that is at stake.
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Again, now in Lewis’s own words, the problem, which global descriptivism
“leads straight to”, is that:
For any world (almost), whatever it is like, can satisfy any theory (almost), whatever it says. We said: ‘the intended interpretation will be the one, if such there be, …’ Never mind the proviso – there will be. It is (almost) certain that the world will afford the makings of an interpretation that will make the theory come true. In fact, it will afford countless such interpretations. Ex hypothesi these interpretations are intended. So there is (almost) no way that the theory can fail to come true on its intended interpretations. Which is to say: (almost) no way that the theory can fail to come true simpliciter. This is Putnam’s so-called ‘model-theoretic argument.’23
The inevitability of countless intention-respecting interpretations is due to the size
or cardinality of the model and domain considered (recall: “… a domain need only
be large enough.”) – that is why it is not necessarily a problem for the more modest
local descriptivism, namely because there will not necessarily be enough “room” in
the vocabulary to compensate by predicate- and description-shifting for whatever
changes are made to the given model (e.g., making the model count “pigs are
winged animals” as coming out true by means of bizarre reference-fixing
descriptions for “winged” and “animal”). But if the vocabulary and domain are
large enough – and there is no problem or even implausibility with taking them
both to be infinite – then this capacity becomes an inevitability due to elementary
model theory.
And so we have arrived at Lewis’s dilemma (really, a trilemma – i.e., the
paradox):
So global descriptivism is false; or Putnam’s incredible thesis is true; or there is something wrong with the presuppositions of our whole line of thought. Unlike Putnam, I resolutely eliminate the second and third alternatives. The one that remains must therefore be the truth. Global descriptivism stands refuted. It may be part of the truth about reference, but it cannot be the whole story. There must be some additional constraint on reference: some constraint that might, if we are unlucky in our theorizing, eliminate all the allegedly intended interpretations that make the theory come true.
23 Ibid. 224
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The problem with this line of approach was already noted by Putnam in the last
section: what might such a constraint look like? What could it be, if not an
intended operational or theoretical constraint, which would therefore by
stipulation be conformed to by an ideal theory?
As I have already mentioned, this is why Lewis chooses descriptivism as the
theory of reference that applies to the term-introducing ideal theory in question –
because it naturally exhibits this capacity for “pre-empting” all potential
constraints that could be added to ideal theory. As Lewis says, global descriptivism
is “imperialistic: it will annex any satisfactory alternative account of constraints on
reference.”24 The essential reason for this is quite simple: any constraint that we
might come up with, insofar as we can articulate it at all, will be able to be framed
descriptively.
For instance, at least since Saul Kripke’s Naming and Necessity, “[m]any
philosophers” searching for a constraint that could secure determinate reference
would “suggest at once that the saving constraint has to do with the causal chains
that lead into the referrer’s head from the external things that he refers to.”25 Of
course the problem with this, as Kripke himself acknowledged, is that such a
causal theory is annexable by descriptivism, which produces what Lewis calls
“causal descriptivism”: “descriptivism, local or global, in which the descriptions
are largely couched in causal terms. […] When causal theories work, causal
descriptivism works too.”26 Again, any causal constraint can be framed
descriptively and thus automatically annexed into the globally descriptivistic ideal
theory. Lewis thus takes the lesson of Putnam’s Paradox for causal theorists to be
24 Ibid. 22525 Ibid. 22626 Ibid. 226-7
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“don’t trade in your genuine causal theory for causal descriptivism.”27 But Lewis
likes descriptivism, and he prefers causal descriptivism to a genuine causal
theory28, which forces him to look elsewhere for his externalist constraint on
reference and referential theory:
I am inclined to favor a different kind of constraint proposed by G. H. Merrill. […] This constraint looks not to the speech and thought of those who refer, and not to their causal connections to the world, but rather to the referents themselves. And among all the countless things and classes that there are, most are miscellaneous, gerrymandered, ill-demarcated. Only an elite minority are carved at the joints, so that their boundaries are established by objective sameness and difference in nature. Only these elite things and classes are eligible to serve as referents. The world – any world – has the makings of many interpretations that satisfy many theories; but most of these interpretations are disqualified because they employ ineligible referents. When we limit ourselves to the eligible interpretations, the ones that respect the objective joints in nature, there is no longer any guarantee that (almost) any world can satisfy (almost) any theory.29
In Catherine Elgin’s words, Lewis notes that reference “is a two-place relation.
What one of the relata cannot do, the other may be able to. So even if we cannot
disqualify motley collections from serving as extensions of our terms and truth
makers of our theories, it does not follow that they are qualified. For the world may
disqualify them for us.”30
Lewis terms his proposed realist criterion of eligibility of referents for
reference (in predicates) or of “joint-carvingness” (of properties) naturalness.
Roughly, the idea is this. The world is objectively structured in a mind-independent
fashion – it is “carved at the joints”31. To say that nature is “carved” means that the
objective structure of the world divides the contents of the world into distinct
27 Ibid. 22628 For one, as Sider notes: “[A] pure causal theory is likely to be insufficiently general. We need to rule out incorrect interpretations of mathematical and logical language, for example – as put forward by Skolemite skeptics about set-theoretic language, say, or Kripke’s Wittgenstein […] and it is hard to see how a pure causal account could do this” (Sider, Writing the Book of the World 33).29 Lewis, “Putnam’s Paradox” 22730 Elgin, “Unnatural Science” 29031 Lewis, “Putnam’s Paradox” 227
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classes or extensions, and to say that it is carved “at the joints” means that these
dividing lines are drawn on the basis of perfectly natural properties, the
fundamental “joints” of reality. In other words, some properties and class
distinctions are more fundamental than others – e.g., plausibly quark spin is a
more fundamental property than that of, say, being a pig, not to mention that of
being-a-pig-or-a-star-or-weighing-256-pounds. The former seems to correspond to
an objective, and relatively fundamental, property, while the latter, especially the
disjunctive version, seems to be an essentially arbitrary, artificial, or gruesomely
“gerrymandered” property – at any rate, a less “natural” one.
For Lewis naturalness “grades off”32 – there are perfectly natural properties,
the truly fundamental joints in nature, and successively less natural properties, all
the way up to the most gruesomely disjunctive ones and beyond. As Elgin says,
“[t]he real metaphysical divide comes between perfectly natural properties and all
the rest33, but if the perfectly natural properties are given, they can constitute a
standard for assessing comparative naturalness: “A property or relation is more or
less natural, [Lewis] said, depending on how short a definition it can be given in a
perfectly natural language – a language in which all predicates stand for perfectly
natural properties and relations.”34
Now, a common way of identifying these perfectly natural properties is in
terms of the requirements of physics or of ideal physics, e.g.: the perfectly natural
32 “Merrill makes eligibility an all-or-nothing matter; I would prefer to make it a matter of degree. The mereological sum of the coffee in my cup, the ink in this sentence, a nearby sparrow, and my left shoe is a miscellaneous mess of an object, yet its boundaries are by no means unrelated to the joints in nature. It is an eligible referent, but less eligible than some others. (I have just referred to it.) Likewise the metal things are less of an elite, eligible class than the silver things, and the green things are worse, and the grue things are worse still – but all these classes belong to the elite compared to the countless utterly miscellaneous classes of thing that there are” (Ibid. 227).33 Elgin, “Unnatural Science” 29134 Sider, Writing the Book of the World 130
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properties, the fundamental joints of nature, are those which are required by ideal
physical theory (or whose existence is entailed by the true sentences of the
theory). However, we should be wary of taking metaphysical realists like Lewis to
define the perfectly natural properties in this way – the idea is that ideal theory
should aspire to capture or respect those already- and objectively-existing
demarcations, not that the natural properties should be taken as a function or
“output” of theory. Indeed, as we will see, this latter kind of view would essentially
constitute a pragmatic understanding of realism, as elaborated by e.g. Elgin. But
for the Lewisian realist, we should construct our predicates so as to correspond to
natural properties – not infer the properties from our predicates, i.e. not read our
ontology off our language/theory.
It is perhaps not obvious how Lewisian naturalness serves to defray the
paradox, so a few words on this are in order.
Recall the pig example. Say the formula is “has wings”. In our actual
language or with regard to our actual intended meanings, of course, “a pig has
wings” ought to come out false. But we can construct an alternative interpretation
on which it comes out true – and on which all the other sentences of the language
come out true (i.e., the interpretation is internally consistent) – given merely the
basic model-theoretic constraints outlined above. That is, the point was that, given
sufficient cardinality of the language’s non-logical vocabulary and domain, there
will always be “room” to compensate for bizarre interpretations by making other
bizarre interpretations: e.g., we could interpret “has wings” as corresponding in
meaning to “is edible” and “pig” as meaning “hard-boiled eggs” (so that “a pig has
wings” is true because hard-boiled eggs are edible).Obviously, changes such as
these would require further compensations, but as Ted Sider says, “The argument
Allen Porter | 25
assumes that it is possible to continue selecting meanings for the nonlogical
expressions in our language so that every member of S [the sentences in the
language] (and (F) as well [a sentence that intuitively should be false in the
language, such as “pigs have wings”]) turns out true. But this will always be
possible, except in special cases”35 (namely cases whose exclusion is already built
into the argument’s structure – i.e., cases where (F) is inconsistent with S or where
they only have models larger than the domain).
So how does the criterion of naturalness serve to disqualify the bizarre
interpretation? Well, in a word, simply because the latter is unnatural, i.e. deploys
predicates corresponding to unnatural properties. Presumably, being a pig, being
edible, etc. are relatively natural properties – i.e., they can be defined in terms of
perfectly natural properties in a language all the predicates of which correspond to
perfectly natural properties; in other words, these properties are “built up from”
more and ultimately the fundamental building blocks of physical reality (a pig is
composed of molecules which are composed of atoms etc. etc.). But it seems less
plausible that a being a winged pig (something that does not actually, physically
exist) or a gruesome property like being-a-winged-pig-or-a-unicorn-or-… could be
grounded in this way in the fundamental joints of reality.
Actually, strictly speaking, this is inaccurate because too strong. Presumably
the property of being a winged pig (and even the disjunctive version) is not so
unnatural as to be completely ineligible for reference – indeed, I have just referred
to it. After all, pigs are relatively natural, as are wings, it is just the combination
that is unnatural. The point, noted above, is rather one of comparative naturalness.
The Lewisian realist does not need naturalness to absolutely disqualify unnatural
properties from reference – rather, the criterion is needed to disqualify some 35 Ibid. 25
Allen Porter | 26
unnatural property relative to a more natural one. That is, the realist does not
require that a bizarre interpretation of “pig” or “animal” be disqualified as
unnatural simpliciter, but rather that it be unnatural and therefore ineligible
relative to a more natural interpretation. Again, given the perfectly natural
properties and a language with only perfectly natural predicates, competing
interpretations can be assessed comparatively in terms of naturalness, such that
e.g. the interpretation that takes “pig” as referring to airplanes or hard-boiled eggs
(plus all the other compensations that would be required) is disqualified in
comparison with one that takes “pig” to refer to pigs, and so on.
So Lewis’s is a classically metaphysical realism: truth ultimately does not
depend on us – for even if we cannot differentiate some one ideal model from
infinite isomorphic alternatives as being the true one, the world or nature (it is
posited) can and does do it; hence the externalist, realist constraint: theories
should truly reflect objective reality, which means that for predicates to
correspond to properties, they must be natural. And this is not a constraint internal
to or annexable by globally descriptivistic theory (adding it to the theory in
description form accomplishes nothing), because it is an external constraint upon
such theory – and this because naturalness and hence eligibility for reference is
determined on the properties-end of the “language-world” relation, not (as with
Putnam’s use of Tarski’s semantic definition of truth) on the predicates-end.
But is this solution tenable?
IV. Catherine Elgin’s Pragmatic Objections to the Lewisian Solution
Catherine Elgin’s objections to Lewis’s solution provide a good lead-in to the
Putnamian solution to the paradox that I ultimately favor – for one, because they
Allen Porter | 27
are rooted in pragmatic concerns of precisely the kind that motivate Putnam’s
pragmatic or “internal” realism. If the critique is valid and the Lewisian solution is
pragmatically defective, this is good motivation to consider a pragmatic alternative
to metaphysical realism.
Elgin approaches the problem from the perspective of the philosophy of
science, since it is essentially scientific theories that are in question with the
notion of an “ideal theory” – what else would an ideal theory that correctly
predicted all observation sentences and consistently assigned reference to all
referential terms (including, e.g., the terms of fundamental physics) be, if not
“total theory”, as Lewis says, i.e. the total theory of science (“total science”)?
And it is from the perspective of actual scientific practice that Elgin
critiques Lewis’s notion of naturalness as a realist criterion for eligibility of
reference. The core of her pragmatic critique, which could perhaps be labeled an
“argument from evolutionary adaptation”, can be summarized as follows: “The
worry is this: the factors that distinguish eligible from ineligible referents must be
independent of us; otherwise, they are of no help against Putnam. But if they are
genuinely independent, it is hard to see how they can do any epistemological
work.”36
This is the core of the pragmatic critique, and the issue that motivates
Putnamian internal realism: it is that metaphysical realism does no work – it is a
pure and unverifiable metaphysical posit, the positing of which does not contribute
to or inform or guide actual practice at all. As Putnam says, “internal realism is all
the realism we need” – and if internal realism is adequate for guiding actual
practice, including guiding it toward the end of discovering whether or not the
thesis of metaphysical realism holds (i.e. whether or not there is some one 36 Elgin, “Unnatural Science” 293-4
Allen Porter | 28
objective model of the world), then it would simply be premature to project what
should properly be an empirical result of inquiry in advance as an axiomatic posit.
So to make the point let us grant Lewis his realist metaphysics. Let us grant
the objective structure of the world – its objective “carving” into extensions, the
objective hierarchy of grading-off naturalism of properties, etc. Then the question
is: what work does this do for current theory, for the current practice of
theorization as it aspires to idealness? Actually, there are two questions: firstly,
granted that natural properties exist, does that necessarily mean that the end of
scientific theory is to discover them (in epistemology, this question is often framed
in terms of truth’s being “the primary epistemic goal”)? – and, secondly, does
projecting this ideal goal in any way benefit practice over and above the way a
more deflationary, semantic notion of truth can?
The title of Elgin’s article alludes to the first question, since she argues that
science might have pragmatic reasons to be concerned with unnatural properties –
and it will be with regards to the second that she then rejects the Lewisian
conceptual and terminological framework, arguing that rather than saying that
science might have good reason to “go unnatural”37, we should just index the
notion of naturalness to theory in the first place. In other words, she makes the
internal realist argument that the determination of naturalness should be an
empirical conclusion drawn from, or should be the “output” of, the practice of
scientific theorization at its ideal limit – properties read off ideal theory’s
predicates – rather than an antecedently and axiomatically asserted metaphysical
posit.
In short, Elgin implicitly presents Lewis with a new dilemma: either
naturalness is a pure metaphysical posit, unverifiable until the ideal end of 37 Ibid. 296
Allen Porter | 29
scientific inquiry and pragmatically irrelevant to that inquiry up to that point, or it
is a function of successful theory, something to be drawn as a conclusion from the
actual practice of theoretical inquiry, and hence an essentially pragmatic or
epistemological criterion rather than a metaphysical one. Or even shorter: either
realism is irrelevant or it is internal rather than metaphysical realism. So let us
examine exactly how she gets there.
Recall the functionality of Lewis’s realist criterion of referential eligibility. It
works comparatively: one interpretation or theory is disqualified for reference
relative to a more natural one, where comparative naturalness is determined by
the length of the “chains of definability” connecting the theories’ predicates to the
predicates of a perfectly natural language, i.e. a language all the predicates of
which correspond to perfectly natural properties. This means that in order for
naturalness to effectively serve as a practical criterion for theory-selection or -
determination, two things are required: first, we must know what the perfectly
natural properties are (so that we can construct a perfectly natural language to
serve as the objective standard for comparative assessments of naturalness), and
second, we must be able to construct the required chains of definition connecting
less-natural theoretical predicates to those of the perfectly natural language.
And if the thesis of metaphysical realism is in fact true, then it is plausible
that at the ideal end of scientific inquiry, we will have a theory of physics whose
required predicates are perfectly natural; it is even possible – though this is much
less plausible, I think – that we will be able to construct the required chains of
definability from the predicates of less-fundamental theories to the perfectly
natural ones of fundamental physics.
Allen Porter | 30
But here is the reality, the reality that is relevant to actual scientific
practice: currently, we do not know which properties are perfectly natural, and
even if we “optimistically assume that our current best candidates – quark colors
and flavors and the like – are, or come very close to being perfectly natural
properties”, we still “have no idea”38 of how to construct chains of definability
linking natural properties, such as would figure in specialized sciences like geology
or biology, to the perfectly natural ones. And this is a major problem, at least if
naturalness is to constrain or guide scientific practice at all, i.e. with regards to the
determination and comparative assessment of theories.
For instance, take the theoretical constraint of simplicity. On the Lewisian
realist view, it makes sense that theoretical simplicity would be a function of
naturalness – natural predicates would be simpler than more gruesome, e.g.
disjunctive predicates, hence natural theories would be simpler than unnatural
ones. But if simplicity is a function of naturalness is a function of the perfectly
natural properties that would figure in ideal physics, then if we cannot identify the
perfectly natural properties or define natural properties in terms of them, then
“they cannot figure in our assessments of simplicity. Judgments must be made on
the basis of available information.”39
On the other hand, the kind of simplicity that scientists are in a position to
assess (and plausibly the only kind they are interested in anyway) is “simplicity
relative to a scheme of organization whose evolution was fraught with
contingencies [… and with regards to which] there is no reason to believe it affords
the only such structure or the best one.”40 Whether or not a theory is the only such
or best one is an irrelevant consideration for actual scientific practice, i.e. from a 38 Ibid. 29539 Ibid. 29540 Ibid. 295
Allen Porter | 31
pragmatic standpoint – these kinds of determinations should properly be empirical
results of successful theorization, not guiding principles. As Elgin notes, “In fact,
scientists assess simplicity on the basis of whatever scheme of classification
happens to be in effect. Contemporary geologists cheerfully use contemporary
geological categories, undaunted by the knowledge that historical contingencies
affected their development.”
This means that, even if there are natural properties, we simply might not be
interested in them, because the world that we have epistemological access to and
are evolutionarily adapted for might be gruesomely unnatural. Indeed, it would be
a “remarkable” result (and, note, still a result!) if “a taxonomy that draws the
distinction between horses and zebras where we do” – i.e. as dependent on our
contingent history, the perceptible environment that we are evolutionarily adapted
to, our pragmatic interests, etc. – “aligned at all well with natural categories
suitable for describing the cosmos as a whole, but indifferent to human faculties
and ends.”41
That is, even if reality does privilege some sparse set of properties as
perfectly natural (those that would figure in ideal physics), it is hard to see how
these could ground an objective fact of the matter as to whether, e.g., the way we
draw the distinction between horses and zebras is the right or true way (and much
harder to see how we could make the required definitional connections). And that
is because this distinction, like so many in science, is a function of our contingent
evolutionary makeup and connected pragmatic interests, so it is hard to imagine
that ultimate reality would decide one way or another about it – just as it seems
very implausible that the fundamental joint-carving facts about the perfectly
natural properties of reality might be capable of determinately grounding an 41 Ibid. 297
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objective fact of the matter as to whether it is right to put the salad fork to the left
or to the right of the dinner fork (for even etiquette can be scientifically theorized).
Or even take a less controversial and more fundamental case:
Isotopes could as easily be construed as different types of atom or as variants of the same type of atom. Given certain reasonable interests that predominated in the development of physics, it makes sense to construe them as variants. But if we bracket those interests, there may be no ground for favoring either construal over the other. Physics could, I suggest, progress equally well under either scheme.42
The ultimate and overarching point is simply that science is essentially and
thoroughly pragmatic: there are multiple desiderata for scientific theorization, and
there “is no reason to think that only theories that restrict themselves to natural
properties [even waiving the above problems inherent with this vis-à-vis actual
practice] will satisfy our scientific desiderata.”43 There would be reason to think
this – granting Lewisian metaphysics and, again, assuming the above difficulties
resolved – if the only or primary goal of scientific theory was truth. But this is
theoretically implausible and clearly at odds with the realities of actual scientific
practice.
As Elgin puts it, “Truth is cheap – far too cheap to qualify as the end of
inquiry. […] For philosophy of science, the important lesson of the Putnam-Lewis
dispute is that we cannot construe (mere) truth as the end of scientific inquiry.
Not, as the skeptic contends, because truth is too hard to come by, but because it
is too easy.”44 Too easy, because it is “an all but inevitable side-effect of satisfying
scientific ideals, whatever they may be.”45 That is, for an ideal theory that meets all
theoretical and operational constraints (really even for a non-ideal theory that is at
least consistent and of large enough cardinality), truth falls out as a matter of
42 Ibid. 297-843 Ibid. 29844 Ibid. 300-145 Ibid. 300
Allen Porter | 33
course – indeed, this just is the upshot of the model-theoretic argument. An
inelegant and implausible but consistent and large enough theory is no less true
than an elegant and plausible isomorphic alternative – if the former is deficient, it
is with regards to other scientific desiderata. A realist would dispute this, and a
Lewisian realist would attempt to ground all other scientific desiderata in that of a
theory’s being true qua being natural, but we have already seen the problems with
this.
In short, science is pragmatic – its goal should be the immanent one of being
successful (according to its own internal scientific standards) rather than the
transcendent one of discovering a purely putative objective truth; right in line with
Putnam, Elgin is arguing that ideal science is successful science (that it is also true
science is, again, a rather trivial side-effect of its being ideal): “For the purposes
of science, all schemes of organization that enable us to make maximally good
sense of things are equally worthy, and are preferable to any scheme that at its
best enables us to make less good sense than its rivals. And making good sense has
to be measured by our own standards, for we have no other.”46
And, as further support for the implausibility of taking truth to be this kind
of fundamental epistemic goal (and as a transition into the next section), consider a
promising pragmatic alternative: understanding. Without going into the details of
the notion, which I understand along broadly Wittgensteinian-Sellarsian lines, it
suffices here to simply characterize pragmatic understanding in terms of an ability
to do rather than a knowledge that. When we understand a scientific term, we
know how to use it – how it functionally interrelates with the other terms of our
theories, how it can figure in inferential activity, whether we should count a given
sentence it figures in as true, etc. Likewise for a theory or part of a theory, and in 46 Ibid. 300
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opposition to truth-functional knowledge. Plausibly, the goal of understanding –
because purely pragmatically/internally defined – could function (for actual
practice) as the fundamental goal of scientific inquiry, insofar as the achievement
of other desiderata can be framed in terms of it (i.e., insofar as successful or ideal
theory, qua successful/ideal, can be framed in terms of it – truth, again, being an
essentially automatic side-effect of successful theory):
Truth is guaranteed, practically irrespective of our cognitive desiderata. So we cannot justify particular desiderata by claiming that their satisfaction is especially conducive to getting truth. What can we say in their favor? Adopt one set of desiderata and complexity is a cognitive virtue. Adopt another, and simplicity is. Both can figure in ideal theories. So what – if anything – is to be said in favor of simplicity? Is there just no disputing matters of theoretical taste? Rather, I suggest, the answer is this: in our scientific investigations, we seek an understanding of a certain kind. The value of simplicity, scope, informativeness, and the like derives from their contributing to the advancement of that sort of understanding. Their merit lies not just in their yielding truths, but in their yielding truths of a certain kind.47
And the same goes for naturalness – naturalness should be empirically read off
from successful theory, as a function of yielding scientifically useful truths, not
postulated prematurely as a transcendent principle of inquiry:
Lewis’s conviction that the naturalness of properties is independent of and antecedent to scientific inquiry recalls the Euthyphro problem. In The Euthyphro, the question was, roughly: Is an action good because the gods like it, or do the gods like it because it is good? The counterpart is: Does science favor particular properties because they are natural, or are they natural because science favors them? […] Without commenting on the persuasiveness of Plato’s argument about goodness [i.e., concluding that the gods favor the good because it is good, rather than its goodness deriving from their favor], I suggest that the answer to our question does not run parallel. Nothing confers naturalness on properties but their contribution to successful science. Properties are natural, then, only because natural science favors them. Naturalness of properties is an output of successful inquiry, not an input into it.48
If there is an objective truth of, or an objectively true model of, reality, then
science will discover it at the ideal end of inquiry – an inquiry guided by immanent
or internal pragmatic constraints, which would garner no benefit from the
inclusion or assumption of the metaphysical realist thesis; that is, at the ideal end 47 Ibid. 300-148 Ibid. 300
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of scientific inquiry, if theories should happen to converge perfectly, then
pragmatic truths will have delivered metaphysical truth – and if they do not, if
there is no (accessible) ultimate best theory but only multiple good theories, then it
is not as though we lose objectivity (at least not in any important sense). We would
still have the kind of relative or epistemological objectivity that can be determined
in terms of theory-comparison, e.g. where and how theories do partially converge.
We would lose metaphysical objectivity, which might be comforting, but not
pragmatic objectivity, which is necessary for the practice of science.
Even if Kant was right about morality as an ideal end – that the actual
practice of building a moral society requires the “postulates of pure practical
reason”, e.g. the existence of God, so that we do not lose heart and give up on the
task as futile – this “solution” seems utterly out of place with regards to science;
science delivers its own immanent, pragmatic justification for its practice in the
form of its usefulness or success at allowing us to understand our world, and I do
not think that scientists would lose heart and give up on their practice if they were
to come to believe that there is no one best scientific theory that captures the
ultimate truth of reality.
V. Putnamian Internal Realism
If the foregoing has been on point, it would seem we have more than
sufficient philosophical motivation to consider a pragmatic alternative to
metaphysical realism. In this section I will present a more precise sketch of what
such a pragmatic alternative might consist in, based in Putnam’s own explication
of his “internal realism” in “Realism and Reason” and “Models and Reality”. I will
also show how Quine, whom Putnam aligns himself with in “Models and Reality”,
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essentially prefigured or anticipated both Putnam’s challenge and internal realist
solution several years earlier in “Ontological Relativity”.
As I have mentioned, in “Models and Reality”, Putnam frames the model-
theoretic argument as an extension of the Löwenheim-Skolem Paradox into the
philosophy of language. The details of this extension are unimportant for the
purposes of this paper; what is relevant is how Putnam analogically describes his
take on realism in terms of the philosophy of mathematics (and, more generally,
the philosophy of science).
Putnam notes in the beginning of “Models and Reality” that in many
different areas of science (though in much of his discussion he focuses on
mathematics, and in “Realism and Reason” explicitly draws the analogy between
verificationism and mathematical Intuitionism49) there are “three main positions on
reference and truth”: Platonic realism, “which posits nonnatural mental powers of
directly ‘grasping’ forms (it is characteristic of this position that ‘understanding’ or
‘grasping’ is itself an irreducible and unexplicated notion)”; verificationism, “which
replaces the classical notion of truth with the notion of verification or proof, at
least when it comes to describing how the language is understood”; and finally
“the moderate realist position which seeks to preserve the centrality of the
classical notions of truth and reference without postulating nonnatural mental
powers.”50 Putnam’s model-theoretic challenge, of course, is aimed at this last,
“moderate” version of realism, as the verificationist position corresponds to
pragmatism, and since a realism that posited non-natural mental powers of
grasping truth would thereby evade the problem (namely, we would be able to tell
49 Putnam, “Realism and Reason” 48750 Putnam, “Models and Reality” 464
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which model is the true one because we would have a faculty for directly grasping
objective truth).
Later in the paper he expands upon this characterization, and what he had
framed as verificationism he now identifies as the “radical pragmatist wing,
represented, perhaps, by Quine”, which is “willing to give up the intuition that [an
ideal model] might be false ‘in reality’.”51 He says that this position is still “realist”
in the sense of regarding science, “taken more or less at face value”, as being “at
least approximately true; ‘realist’ in the sense of regarding reference as trans-
theoretic […] but not metaphysical realist.”52
In other words, for the internal realist, truth is still rooted in some objective
reality, such that progress in scientific theorizing can be reference- and therefore
truth-preserving (i.e., the new theories resulting from scientific breakthroughs and
revolutions typically do not simply undermine the sentences/‘truths’ of previous
theories, they rather preserve them in a relative fashion by “putting them into their
place”, so to speak – as when Euclidean geometry and Newtonian physics came to
be understood within the new theoretical frameworks of non-Euclidean geometry
and relativity theory). But there is no claim as to the metaphysical status of this
objective reality – perhaps the idealists are right, and there is only an
epistemological or mind-dependent reality; nevertheless, there would still be
objectivity in the form of inter-subjectivity.
Of course, this argument is not wedded to idealism – it can be fruitfully
applied, e.g., to questions of convention: is there an objective fact of the matter
whether one should put the dinner fork here or there? Well, it is doubtful that
there is a metaphysical fact of the matter – but there are facts (more precisely,
51 Ibid. 47452 Ibid. 474
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norms that can be described or formulated factually) of etiquette that, relative to
some system of convention, are perfectly objective. Similarly, there is nothing
“subjective” about what moves are allowed and disallowed in chess – certainly, one
does not have to “play the game”, but insofar as one commits to playing the game,
the rules are as objective as one could wish.
The analogy of epistemological objectivity as inter-subjectivity is an apt one,
especially if we think in terms of theories rather than individual human minds.
Objectivity is a function not of some reality external to theory, but of the “inter-
theoretical” convergences and divergences of good (successful, pragmatically
effective) theories. The upshot is that realism, conceived in this “internal” way, is
best characterized as being epistemologically explanatory rather than
metaphysically expository; as Putnam says:
In one way of conceiving it, realism is an empirical theory. One of the facts that this theory explains is the fact that scientific theories tend to "converge" in the sense that earlier theories are, very often, limiting cases of later theories (which is why it is possible to regard theoretical terms as preserving their reference across most changes of theory). Another of the facts it explains is the more mundane fact that language-using contributes to getting our goals, achieving satisfaction, or what have you.
The realist explanation, in a nutshell, is not that language mirrors the world but that speakers mirror the world -- i.e., their environment -- in the sense of constructing a symbolic representation of that environment. In "Reference and Understanding" I argued that a "correspondence" between words and sets of things (formally, a satisfaction relation, in the sense of Tarski) can be viewed as part of an explanatory model of the speakers' collective behavior.
That is, recall the semantic definition of truth. The definition of truth-in-a-
theory, strictly speaking, would be the infinite conjunction of all a theory’s true
sentences or relations of semantic satisfaction – these, all of which could be
captured in schematic form (cf. footnote 5 on p. 5-6), would constitute all the
truths of the theory. In other words, they would constitute a model of the theory;
and where on the metaphysical realist view, this model would be “true” only
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insofar as it accurately corresponded to reality, on the view of internal realism, it
can be viewed as an “explanatory model of the speakers’ collective behavior” – i.e.,
as a model that elucidates how the language is used. Rather than giving the truth
of the world, it would show us what we take truth to be, what sentences we count
as true. This is why Putnam chooses the mathematical analogy of Intuitionism,
which is essentially verificationism in the philosophy of mathematics:
In Intuitionism, knowing the meaning of a sentence or predicate consists in associating the sentence or predicate with a procedure which enables one to recognize when one has a proof that the sentence is constructively true (i.e., that it is possible to carry out the constructions that the sentence asserts can be carried out) or that the predicate applies to a certain entity (i.e., that a certain full sentence of the predicate is constructively true. The most striking thing about this standpoint is that the classical notion of truth is nowhere used – the semantics is entirely given in terms of the notion of “constructive proof”, including the semantics of “constructive proof” itself.53
And this is also why internal realism can aptly be described as “epistemological”:
because, to use Wittgenstein’s term, the “bedrock” of theory, the foundational
point at which explanation must end (and theoretical primitives be given), is
epistemological rather than metaphysical – it is composed of the norms of practice
(of language use), rather than of truth-functional facts of metaphysical reality. To
understand a term or sentence is to know how to use it, e.g. in inferential activity,
not to know its truth-conditions. So in terms of the mathematical analogy, Putnam
sees “intuitionism as an example of what Michael Dummett has called ‘non-realist
semantics’ – that is, a semantic theory which holds that a language is completely
understood when a verification procedure is suitably mastered, and not when truth
conditions (in the classical sense) are learned.”54
So, to use Putnam’s famous phrase, it is still the case that “meanings just
ain’t in the head” (and in this regard, truth is like meaning) – because meaning
53 Ibid. 47854 Ibid. 479
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(and truth) is also a function of reference, which depends on the so-to-speak “inter-
subjective objectivity” of social practices and the collective use of language, i.e.
epistemological and pragmatic “bedrock” (“reference is determined by social
practices and by actual physical paradigms, and not just by what goes on inside
any individual speaker”55); and this means that “the realist notions of truth and
reference” ought properly to figure “not in explaining what goes on ‘in the heads’
of speakers, but in explaining the success of language-using [… as] part of an
explanatory theory of the speakers’ interaction with their environment.”56
In other words, the reason that internal realism can be characterized as
verificationist (though, notably, not in the sense of the logical positivists’ sense-
data verificationism) is that the verification norms and procedures are, like their
mathematical Intuitionist analogs, purely internal to a given language – though no
less “objective” for that. The “crucial question”, as Putnam says, is “do we think of
the understanding of the language as consisting in the fact that speakers possess
(collectively if not individually) an evolving network of verification procedures, or
as consisting in their possession of a set of ‘truth conditions’?”57
So how exactly does answering this question in the former rather than the
latter way evade the problem of the model-theoretic argument? Let me introduce
the solution by way of Quine.
In “Ontological Relativity”, Quine delivers a famous naturalist attack on the
hypostatization of meaning by “uncritical semantics”, which he characterizes as
“the myth of a museum in which the exhibits are meanings and the words are
labels. To switch languages is to change the labels. […] Semantics is vitiated by a
pernicious mentalism as long as we regard a man’s semantics as somehow 55 Putnam, “Realism and Reason” 48856 Ibid. 48857 Putnam, “Models and Reality” 480
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determinate in his mind beyond what might be implicit in his dispositions to overt
behavior.”58 And Quine says that when we adopt a “naturalistic view of language
and a behavioral view of meaning”, we give up not just the museum myth of
uncritical semantics, but “an assurance of determinacy”:
Seen according to the museum myth, the words and sentences of a language have their determinate meanings. To discover the meanings of the native’s words we may have to observe his behavior, but still the meanings of the words are supposed to be determinate in the native’s mind, his mental museum, even in cases where behavioral criteria are powerless to discover them for us. When on the other hand we recognize with Dewey that “meaning… is primarily a property of behavior,” we recognize that there are no meanings, nor likenesses nor distinctions of meaning, beyond what are implicit in people’s dispositions to overt behavior. For naturalism the question whether two expressions are alike or unlike in meaning has no determinate answer, known or unknown, except insofar as the answer is settled in principle by people’s speech dispositions, known or unknown. If by these standards there are indeterminate cases, so much the worse for the terminology of meaning and likeness of meaning.59
Quine eventually extends what begins as an attack of the determinacy of
meaning – via the famous “indeterminacy of translation” – to reference. Let me
briefly present Quine’s well-known “gavagai/rabbit” argument and how it leads to
the same conclusion as Putnam’s challenge, a situation which Quine terms
“ontological relativity”; Quine’s own brief remarks as to a solution will then bring
us to how Putnam uses internal realism to accomplish the same end.
Imagine a field linguist studying a completely foreign language. He knows
no word of the native language, but has settled on a working hypothesis as to what
native words or gestures signify assent or dissent in response to ostensive queries.
He is trying to translate the native word “gavagai”, which appears to have
something to do with rabbits in terms of its reference. The problem is that “a
whole rabbit is present when and only when an undetached part of a rabbit is
present; also when and only when a temporal stage of a rabbit is present.”60 So
58 Quine, “Ontological Relativity” 18659 Ibid. 18760 Ibid. 188
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how is the linguist to know whether “gavagai” is meant to refer to “rabbit”,
“undetached rabbit part” or “rabbit stage”?
Quine notes, firstly, that ostension cannot settle the matter. In other words,
repeatedly pointing to a rabbit and to things that are not rabbits and querying
“gavagai?” of the native will not settle whether “gavagai” refers to rabbits or not –
it will be able to establish that, for instance, “gavagai” does not mean “tree” (i.e.,
the native will not assent when queried “gavagai?” in the presence of that stimulus
and in the absence of rabbits), but it will be unable to distinguish between a rabbit
and an undetached part of that rabbit, since one cannot point to a rabbit without
also pointing to an undetached rabbit part, and vice-versa. In short, the problem is
that mastering a term like “rabbit” requires mastering its principle of
individuation, since this is the only thing that distinguishes between rabbits and
undetached rabbit parts and so on.
So how might the matter be settled? Well, the problem is that mastery of a
term like “rabbit” requires mastery of its principle of individuation – and while the
competent English speaker has this for “rabbit” (i.e., we know that “rabbit” does
not refer to “undetached rabbit part”, there is no possibility for confusion in this
regard), the field linguist does not have it for “gavagai”. But what exactly does the
competent speaker of English have in this regard – in other words, how do we, as
English speakers and in English, individuate terms? Quine thinks, quite plausibly,
that key in this regard is quantification, and more broadly the whole “apparatus of
individuation”61 comprising
a cluster of interrelated grammatical particles and constructions: plural endings, pronouns, numerals, the ‘is’ of identity, and its adaptations ‘same’ and ‘other’. It is the cluster of interrelated devices in which quantification becomes central when the regimentation of symbolic logic is imposed. If in his language we could ask the native ‘Is this gavagai the same as that one?’ while making appropriate multiple
61 Ibid. 191
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ostensions, then indeed we would be well on our way to deciding between ‘rabbit’, ‘undetached rabbit part’, and ‘rabbit stage’.62
Thus, in actual practice, what the field linguist does is to progressively and
experimentally translate the English apparatus of individuation into the native
tongue, so that he can ask precisely such questions for purposes of individuation.
He does this by “abstraction and hypothesis”: he “abstracts native particles and
constructions from observed native sentences” and forms “analytical hypotheses”
of translation that associate these abstracted pieces of native language with
English particles and constructions.63
That is how actual practice would probably go – and probably, at least
eventually, successfully. “But,” as Quine says, “I am making a philosophical
point”64, and in this regard, the problem of indeterminacy seems to remain:
But it seems that this method, though laudable in practice and the best we can hope for, does not in principle settle the indeterminacy between ‘rabbit’, ‘undetached rabbit part’, and ‘rabbit stage’. For if one workable over-all system of analytical hypotheses provides for translating a given native expression into ‘is the same as’, perhaps another equally workable but systematically different system would translate that native expression rather into something like ‘belongs with’. Then when in the native language we try to ask ‘Is this gavagai the same as that?’, we could as well be asking ‘Does this gavagai belong with that?’. Insofar, the native’s assent is no objective evidence for translating ‘gavagai’ as ‘rabbit’ rather than ‘undetached rabbit part’ or ‘rabbit stage’.65
And the point is that this indeterminacy of translation infects not only meaning, but
reference; it “cuts across extension and intension alike. The terms ‘rabbit’,
‘undetached rabbit part’, and ‘rabbit stage’ differ not only in meaning; they are
true of different things. Reference itself proves behaviorally inscrutable.” 66
So what is Quine’s solution? In essence – to oversimplify – he says that “it’s
not a problem in our mother tongue.” In other words:
62 Ibid. 18963 Ibid. 189-9064 Ibid. 19165 Ibid. 19066 Ibid. 191
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Within the parochial limits of our own language, we can continue as always to find extensional talk clearer than intensional. For the indeterminacy between ‘rabbit’, ‘rabbit stage’, and the rest depended only on a correlative indeterminacy of translation of the English apparatus of individuation – the apparatus of pronouns, pluralization, identity, numerals, and so on. No such indeterminacy obtrudes so long as we think of this apparatus as given and fixed. Given this apparatus, there is no mystery about extension; terms have the same extension when true of the same things. 67
That is, Quine tells us to “begin by picturing us at home in our language, with all
its predicates and auxiliary devices”, including words like “rabbit”, “rabbit-stage”,
“number”, and so on, and “also the two-place predicates of identity and difference,
and other logical particles.”68 In short, the “whole apparatus of individuation”
mentioned above. And Quine says that this “network of terms and predicates and
auxiliary devices is, in relativity jargon, our frame of reference, or coordinate
system. Relative to it we can and do talk meaningfully and distinctively of rabbits
and parts, numbers and formulas.”69 And this is the solution: as Putnam says,
realism relative to a language is “all the realism we want or need”70 – or as Quine
says, it is
meaningless to ask whether, in general, our terms ‘rabbit’, ‘rabbit part’, ‘number’, etc. really refer respectively to rabbits, rabbit parts, numbers, etc., rather than to some ingeniously permuted denotations. It is meaningless to ask this absolutely; we can meaningfully ask it only relative to some background language. When we ask, “Does ‘rabbit’ really refer to rabbits?” someone can counter with the question: “Refer to rabbits in what sense of ‘rabbits’?” thus launching a regress; and we need the background language to regress into. The background language gives the query sense, if only relative sense; sense relative in turn to it, this background language. Querying reference in any more absolute way would be like asking absolute position, or absolute velocity, rather than position or velocity relative to a given frame of reference.71
In actual practice, we are always working within some “coordinate system”
or given frame of reference; to ask about reference outside the context of any such
referential frame would be like asking about position or velocity absolutely, i.e. not
67 Ibid. 19168 Ibid. 20069 Ibid. 20070 Putnam, “Realism and Reason” 48971 Quine, “Ontological Relativity” 200-201
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in terms of a given coordinate system. Well, how does science respond to such
questions, i.e. about position and velocity not relative to a given coordinate
system? “The answer, of course,” Quine says, “is the relational doctrine of space” –
and he thinks the question of reference requires a parallel answer:
The answer, of course, is the relational doctrine of space; there is no absolute position or velocity; there are just the relations of coordinate systems to one another, and ultimately of things to one another. And I think that the parallel question regarding denotation calls for a parallel answer, a relational theory of what the objects of theories are. What makes sense is to say not what the objects of a theory are, absolutely speaking, but how one theory of objects is interpretable or reinterpretable in another. […] The relativistic thesis to which we have come is this, to repeat: it makes no sense to say what the objects of a theory are, beyond saying how to interpret or reinterpret that theory in another. 72
In the terms I used above, truth cannot be extracted from the theoretical domain
and projected into the metaphysical – which means that it is metaphysically
indeterminate, but still epistemologically objective in the inter-theoretical sense.
This is the view from which Quine – who could here be read as essentially
paraphrasing a famous dictum of that favorite target of analytic philosophers,
Jacques Derrida, who claimed “there is no outside-the-text” – can say that “It is
thus meaningless within the theory to say which of the various possible models of
our theory-form is our real or intended model” 73 (because there is no, at least no
epistemologically accessible, transcendent perspective from “outside-the-theory”
from which to assess it in these terms).
And Putnam’s solution aligns with Quine’s in this regard quite nicely. Quine
asserted that it was meaningless to ask whether some term of ours really refers to
what we take it to (e.g. “rabbits” to rabbits rather than rabbit-stages or other
gerrymandered alternatives) except relative to some background language; if we
are using some object language, when asked e.g. “In virtue of what does ‘pig’ refer
to pigs?”, then we can give some fact in the metalanguage which “gives the query 72 Ibid. 201-20273 Ibid. 204
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sense, if only relative sense”74 (relative to the background metalanguage). But
when the object language is the metalanguage, when we are “at home” and
speaking in our mother tongue, there is no further background language that we
can retreat to; here we hit bedrock, as it were, and the question becomes
meaningless – at least, if it is asking after some metaphysical fact that would
determine the matter. For this is epistemological bedrock, the domain of use and
practice, and whatever “facts” there may be here are facts of usage, so really
norms. “How do you know that ‘pig’ refers to pigs?” – “Because that is how the
language is used.” That’s how we play the game – and while this response does
nothing to settle the metaphysical determinacy of the references employed, it
perfectly adequately identifies an epistemological determinacy – all the
determinacy we need.
As Putnam puts it,
Suppose we try to stump the internal realist with the question, “How do you know that ‘cow’ refers to cows?” […] The internal realist should reply that “‘Cow’ refers to cows” follows immediately from the definition of “refers” […:] relative to the theory, “‘Cow’ refers to cows” is a logical truth. […]
What I am saying is that, in a certain “contextual” sense, it is an a priori truth that ‘cow’ refers to a determinate class of things (or a more-or-less determinate class of things – I neglect ordinary vagueness). Adopting “cow talk” is adopting a “version”, in Nelson Goodman’s phrase, from within which it is a priori that the word ‘cow’ refers (and, indeed, that it refers to cows). 75
When Putnam says that “‘Cow’ refers to cows” follows immediately from the
definition of “refers”, he is essentially just taking reference to be defined in terms
of semantic satisfaction. That is, he takes reference, like truth, to be “defined
implicitly through instances of” Tarski’s Schema T – so that there is then “no
further question to be asked in virtue of what ‘s’ refers to s. It simply follows from
the meaning of the word ‘refers’ that instances of the schema are true.” 76 Note, 74 Ibid. 20175 Putnam, “Realism and Reason” 494-576 Frisch 163
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again, that we need not take this to be deflationary in any significant way – it is
simply the epistemologically explanatory rather than metaphysically expository
nature of truth and reference.
VI. Conclusion
I have been working on this paper on and off for nearly a year now; the first
version (this being essentially the third), which I drafted for an independent study
in the philosophy of language, saw me siding with Lewis and Sider against Putnam
and Elgin. I include this autobiographical detail in order to bring out how
compelling (metaphysical) realism about truth can be, especially at the
pretheoretical level of ordinary intuition. At first glance – or simply given certain,
perhaps unconscious, presuppositions – Putnam’s challenge can easily seem like
the “bomb” that Lewis took it to be (and I do not doubt many retain this attitude
even after sufficient reflection – after all, Bourget and Chalmers’ 2009 survey
found that a majority of philosophers polled were moral realists (56.3%), and an
even higher percentage were what I have been calling metaphysical realists (75% –
the highest percentage of all categories, just exceeding atheism’s 72.8%)). But,
obviously, I no longer find this to be the case.
In the end, at least for me, the issue is simple, and simply one of intellectual
rigor, or what Nietzsche called his “intellectual conscience” – and it is captured in
the question: Is there any good philosophical (as opposed to, e.g., psychological)
reason to adopt metaphysical realism, to not settle for an epistemological or
pragmatic conception of truth – or alternatively, what do we lose by settling for a
“merely” semantic conception of truth and reference, other than the mere idea of
metaphysical realist truth? It may seem like we lose everything – all objectivity, all
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hope for achieving a determinate consensus on what is true and what is not,
objective reality itself even; however, I hope this paper has made a persuasive case
against this conclusion.
In other words, I do not see the issue as running parallel to Nietzsche’s
confrontation with Kant, i.e. with regard to the postulates of pure practical reason
– for Nietzsche was the first to admit that many people do require this kind of
transcendent grounding for their beliefs and behavior (though of course he
derisively thought of these people as members of the herd, as unenlightened or
“immature” in Kant’s words). No such transcendent support is needed, nor should
it be wanted, in science, which is the immanent and pragmatic pursuit par
excellence. We do not require a transcendent justification of science – for unlike
morality, which will always have its Thrasymachan skeptics who claim that being
immoral is the pragmatically advantageous option, science immanently proves its
own value through its use(fulness). There is no question of whether being un- or
anti-scientific might not be more pragmatically beneficial than the opposite. This is
why metaphysical realism does no work – because whether we include it in our
theory or not, we go on the same way, a way which will eventually decide the
question empirically, a task made none the easier by presupposing this question
decided at the outset.
I have perhaps worded things rather strongly in this paper, by saying that
metaphysical realism should “properly” only be an empirical conclusion drawn at
the ideal limit of inquiry – which would seem to disqualify it wholesale as a
metaphysical view until then (and so for everyone, e.g. those 75% of professional
philosophers, now). But of course metaphysical realism is a philosophical position
whose scope and implications extend beyond the issues considered in this paper,
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fundamental as they may be – for example, many philosophers might want
metaphysical realism as a support for moral realism, a position they hold
independently. Or others, perhaps, simply find themselves unable to abandon the
familiar and beloved position – perhaps they have a direct intuition about it, for
instance.
So I do not mean to argue that no one should be a metaphysical realist until
we in fact empirically discover whether its thesis is the case or not. What I am
arguing is that there is no kind of necessity for metaphysical realism, at least with
regards to the question of truth – and further, in this regard, that it does no real
philosophical work. So it is not that I think being a metaphysical realist about truth
is untenable per se, but rather that, at least strictly speaking, metaphysical realism
has no proper place in the analytic philosophy of language (since including its
thesis in that field does accomplishes nothing). I see it rather, not so much as a
philosophical opinion, as a philosophical orientation – if you are a metaphysical
realist, then this will inform much of what you are attracted to in philosophy and
how you go about doing philosophy. And vice-versa: as Putnam says, “Even if it is
not inconsistent with realist semantics, taking the nonrealist semantics as our
picture of how the language is understood undoubtedly will affect the way we view
questions about reality and truth.”77
But while I would not want to tell all the metaphysical realists that their
view is untenable, I would want to ask them to consider the alternative, to consider
what doing without that view would mean – and to make sure that they are
metaphysical realists for the right reasons (whatever those may be – but not fears
about losing scientific objectivity). And my hope would be that they would see that
in this regard they “have nothing to fear but fear itself” – that settling for a 77 Putnam, “Models and Reality” 481
Allen Porter | 50
pragmatic, semantic conception of truth and reference does not mean doing away
with any actual objectivity, but only an unverifiable posit about ultimate reality,
one that makes no difference to actual scientific practice one way or the other.
And, perhaps, that once groundless fears are taken out of the picture, the
pragmatic view proves its own merit anyway, in terms of its epistemological
explanatory value – much as science itself does.
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