Quine. “Two Dogmas of Empiricism” - University of San Diego Home

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Two Dogmas of Empiricism
The Analytic-Synthetic Distinction and Reductionism
Quine’s goals
Modern empiricism has been conditioned in large part by two dogmas.
One is a belief in some fundamental cleavage between truths which
are analytic, or grounded in meanings independently of matters of fact
and truths which are synthetic, or grounded in fact. The other dogma
is reductionism: the belief that each meaningful statement is
equivalent to some logical construct upon terms which refer to
immediate experience…One effect of abandoning them is…a blurring
of the supposed boundary between speculative metaphysics and
natural science. Another effect is a shift toward pragmatism.
• Negative: trashing the “two dogmas” of logical positivism
– the analytic/synthetic distinction
– reductionism
• Positive: “naturalizing philosophy”
– Understanding ontology as a matter of pragmatic decision,
comparable to the natural sciences
Quine’s plan
• Debunk the two central dogmas of Logical Positivism (“Empiricism”)
using circularity arguments to show that we can’t come up with an
adequate non-question-begging account of analyticity is, so out go:
– The analytic/synthetic distinction
– Reductionism: “the belief that each meaningful [factual]
statement is equivalent to some logical construct upon terms
which refer to immediate experience.”
• “Naturalizing” philosophy
– by “blurring the supposed boundary between speculative
metaphysics and natural science” which reflects the distinction
between analytic and synthetic sentences where
– the former are supposed to be the business of philosophy and
the latter the business of the natural sciences.
The Circularity Arguments
Background for analyticity
• A statement is analytic when it is true by virtue of meanings and
independent of fact.
• Kant: an analytic statement is “one that attributes to its subject no
more than is already conceptually contained in the subject.”
• Necessary and contingent propositions (Leibniz: “truth of reason”
vs. “truths of fact”)
– A statement is necessary iff it is
• true at all possible worlds, i.e. it is not logically possible that
it be false (Leibniz)
• its denial is self-contradictory
– A statement is contingent iff it is not necessary
Problems
• Kant’s definition
– restricts the definition to sentences in subject-predicate form
– and is metaphorical: what do we mean by “contained”?
• What is “meaning”? What is synonomy (sameness of meaning)?
• What are logical possibility and necessity?
• What is self-contradiction?
• And what on earth are “possible worlds”?
Analyticity as truth in virtue of meaning alone
• Proposal: a sentence is analytic iff true in virtue of meanings and
independent of fact.
• Problem: What is MEANING?
• The meaning of an expression in the sense that interests us is not
its reference or extension.
– The extension of a singular term is the object it names
– The extension of a general term, or predicate, is the set of
objects of which the general term is true
The extensions of some predicates
• “__ is brown”
– {Ducati, the desk in S 312,…}
• “__is married to__”
– {<Justinian, Theodora>, <Barak, Michelle>, <R.S.M.Baber,
H.E.Baber>,…}
• “__prefers__to__”
– {<Krugman, Clinton, Obama>, <Ducati, Baber’s shoe,
ChewToy>…}
Meanings (Intensions)
• Problem: Analyticity has to be understood in terms of meanings
(intensions) rather than extensions of terms
• But what are these intensions anyway?
• Properties? Individual concepts or Fregean senses?
Quine speaks: Once the theory of meaning is sharply separated
from the theory of reference, it is a short step to recognizing as the
business of a theory of meaning simply the synonomy of linguistic
forms and the analyticity of statements; meanings themselves, as
obscure intermediary entities, may well be abandoned.
• We don’t need intentions—providing we can give an account of
synonomy and analyticity.
Paraphrasing away bad things
Alice and Betty are of the same height
– Surface grammar suggests that this attributes a 3-place relation
to Alice, Betty and Height.
– But we can paraphrase it as
Alice is exactly as tall as Betty
– What we really have is a 2-place relation between Alice and
Betty
– Height has been exorcized!
The Exorcism: paraphrasing away intensions
“Bachelor” and “unmarried male” have the same meaning.
– Surface grammar again suggest that this says there’s a 3-place
on “bachelor,” “unmarried male” and a Meaning.
– But we can paraphrase as
“Bachelor” and “unmarried male” are synonymous
– What we really have is a 2-place relation
– Meanings (intensions) have been exorcized!
Synonomy
• Synonomy: sameness of meaning
• Even if there are no such things as “meanings” we can make do
with synonomy since we can paraphrase away “meanings” in the
way that we paraphrased away heights.
• BUT now we have another problem: what is synonomy!
• And we need synonomy to understand analyticity!
The problem of analyticity confronts us anew.
Two types of analyticity
• Logical truths: If we suppose a prior inventory of logical particles,
comprising ‘no,’ ‘un-,’ ‘if,’ ‘then,’ ‘and,’ etc. then in general a
logical truth is a statement which is true and remains true under all
reinterpretations of its components other than the logical particles.
(1) No unmarried man is married
• The other kind of analyticity
(2) No bachelor is married
• The characteristic of such a statement is that it can be turned into a
logical truth by putting synonyms for synonyms…[But] we still lack a
proper characterization of this second class of analytic
statements…inasmuch as we have had in the above description to
lean on a notion of ‘synonomy’ which is no less in need of
clarification than analyticity itself.
Definition
• There are those who find it soothing to say that the analytic
statements of the second class reduce to those of the first class, the
logical truths, by definition; ‘bachelor,’ for example, is defined as
‘unmarried man
• But what do we mean by definition?
• Every definition is either descriptive, i.e. lexicographical or
explicative or stipulative and neither kind of definition will do the job!
• Dilemma:
– Stipulative definitions only go for a narrow range of cases
– Lexicographical and explicative definitions assume that we
already understand synonomy: for them “definition rests on
synonymy rather than explaining it.”
Descriptive definitions
• Lexicographical (dictionary) definition
– Bachelor =df unmarried male that never has been married
– But we can ask whether dictionary definitions are correct, i.e.
whether they really capture synonomy
• Explication (contextual definition): the purpose…is to improve upon
the definiendum by refining or supplementing its meaning. But even
explication…does rest nevertheless on other pre-existing
synonomies…[T]he purpose of explication is to preserve the usage
of these favored contexts while sharpening the usage of other
contexts.
– Appeals to pre-existing synonomies
• So we’re back to synonomy--and no wiser!
Stipulative definition
• Example: definition of logical operators in terms of primitives
– Example: ‘if p then q’ is defined as ‘not-p or q’
• These definitions aren’t arbitrary but depend on purposes in
formulating artificial languages
• But all they can deliver is analyticity-in-L
• So we can’t appeal to “truth by definition” to understand analyticity.
Interchangeability
A natural suggestion…is that the synonymy of two linguistic forms
consists simply in their interchangeability in all contexts without
change of truth value; interchangeability, in Leibniz’s phrase, salva
veritate.
• Can we understand synonomy as intersubstitutivity salve veritate
(preserving truth value) so that, e.g.?
– “bachelor and “unmarried male” are synonymous comes to
– For any sentence where “bachelor” occurs, “unmarried male”
can be substituted and the truth value of the sentence will stay
the same
The question remains whether interchangeability salve veritate…is a
strong enough condition for synonymy, or whether…some nonsynonymous expressions might be thus interchangeable.
Cognitive Synonomy
• [W]e are not concerned here with synonymy in the sense of
complete identity in psychological associations or poetic
quality…We are concerned only with what may be called cognitive
synonymy
– Compare to Frege’s remarks about senses vs. ideas
• What we need is an account of cognitive synonymy not
presupposing analyticity
• Interchangeability salva veritate is meaningless until relativized to a
language
• Dilemma:
– In a purely extensional language non-synonymous terms are
intersubstitutable salva veritate
– A language rich enough to block the intersubstitutability of nonsynonymous terms presupposes an understanding of analyticity!
Extensional equivalence isn’t synonomy
• “F and G are extensionally equivalent” means that all and only Fs
are Gs
• Fact: All and only creatures with hearts are creatures with kidneys
• BUT “creature with a heart” and “creature with kidneys” aren’t
cognitively synonymous
– Sam believes that fish are creatures with hearts – true
– Sam believes that fish are creatures with kidneys – false
• Sam understands “creatures with hearts” and “creatures with
kidneys” but knowing what these terms mean doesn’t help him here.
• Moral: extensional equivalence doesn’t capture the notion of
synonomy—sameness of meaning—that we want.
Necessity
• Necessarily all and only Fs are Gs does capture synonomy
• It is not the case that necessarily all and only creatures with hearts
are creatures with kidneys.
• It is the case that necessarily all and only bachelors are unmarried
men.
• If Tom understands what “bachelors” and “unmarried men” means
then he knows that Dick and Harry are bachelors if and only if he
knows that Dick and Harry are unmarried men.
• So “bachelors” and “unmarried men” are cognitively synonymous
But we can’t use “necessarily”!
• But “Necessarily all and only Fs are Gs” just says that “All and only
Fs are Gs” is analytic!
• Remember: analyticity is what we were trying to explain but
– We tried to explain it in terms of synonomy and then
– explained synonomy of Fs and Gs in terms of a sentence using
“necessarily”
– But then it turned out that tacking “necessarily” in front of a
sentence just said that that sentence was analytic!
• So an account of analyticity in terms of necessity is circular!
Intersubstitutivity is language relative!
• The richer the language the less intersubstitutivity we get
• Example: sentences of the form “If p then q” and “Not p or q” are
interchangeable in the truth-functional language of propositional
logic
– If today is Wednesday then it’s sunny
• But not in ordinary English where “if p then q” says more.
Extensional language
• Quine’s example of an extensional language is the language of
predicate logic, but so is English minus terms like “necessarily”
• “Any two predicates which agree extensionally (i.e., are true of the
same objects) are interchangeable salve veritate” in such a
language.
• But consider “creature with a heart” and “creature with a kidney”
which are extensionally equivalent.
• [I]nterchangeability salva veritate, if construed in relation to an
extensional language is not a sufficient condition of cognitive
synonymy in the sense needed for deriving analyticity.
A Richer Language
• Ordinary English, a richer language, includes words that can only be
understood if we already understand what analyticity is
• Example: NECESSARILY
• “Necessarily all and only bachelors are unmarried men” just comes
to “’All and only bachelors are unmarried men’ is analytic.”
• If a language contains an intensional adverb ‘necessarily…or other
particles to the same effect, then interchangebility salva veitate in
such a language does afford a sufficient condition of cognitive
synonymy; but such a language is intelligible only if the notion of
analyticity is already clearly understood in advance.
Interchangeability won’t do
• A language in which interchangeability is sufficient for synonomy
must be richer than a purely extensional language.
• And the additional stuff will include words like “necessarily” which
we can’t understand unless we already understand analyticity
• Which is what we were trying to understand in the first place!
• The project is circular (but, sly question, are all circles vicious?)
Semantical Rules
• Quine is alluding to Carnap’s project which we will largely ignore.
• The jist of his worry here is that appeal to semantical rules of a
language, L, to explain analyticity only explains analyticity-in-L.
• But that doesn’t explain analyticity for any other language or, what
we’re after, the notion of analyticity as such.
END PART I (and the First Dogma)
[A] boundary between analytic and synthetic statements simply has
not been drawn. That there is such a distinction to be drawn at all is
an unempirical dogma of empiricists, a metaphysical article of faith.
• We don’t know what analyticity is because
• We still don’t know what synonomy is
• Can we get at the idea of synonomy by appeal to the Verification
Theory of meaning?
Verification Theory & Reductionism
• The verification theory of meaning…is that the meaning of a
statement is the method of empirically confirming or informing it. An
analytic statement is that limiting case which is confirmed no matter
what.
• Statement synonymy is said to be likeness of method of empirical
confirmation or infirmation…[What] is the nature of the relationship
between a statement and the experiences which contribute to or
detract from its confirmation?...The most naïve view…is radical
reductionism. Every meaningful statement is held to be translatable
into a statement (true or false) about immediate experience.
• If this works we can understand analyticity in terms of logical truth
(formal analyticity) and likeness in verification/falsification
conditions!
Phenomenalism: an example of Reductionism
• Mill (and on some interpretations Berkeley) understood physical
objects as “permanent possibilities of sensation.”
• Russell suggests they’re “logical constructions” out of objects of
acquaintance—comparable to “the average plumber”
• Ayer reconstructs phenomenalism as the claim that talk about
physical objects can be “reduced” to talk about experiences
Verificationism and synonomy
• Verificationists assume “that each statement, taken in isolation from
its fellows, can admit of confirmation or information at all.”
• Sentences are synonymous exactly the same experiences count for
and against them.
• A sentence is analytic if all experiences count for it--in effect, if no
experiences count for or against.
Quine’s Holism
Our statements about the external world face the tribunal of sense
experience not individually but only as a corporate body. There is no
firm distinction between a linguistic and factual component of the
truth of any individual statement.
The whale is a mammal (?)
Quine’s Holism
Marriage is between a man and a woman (?)
Empiricism Without the Dogmas
• Some statements are more entrenched than others but all face the
“tribunal of experience” together.
• So no statements are “purely linguistic”
• “The unit of empirical significance is the whole of science”
The Web of Belief
The totality of our so-called knowledge or beliefs, from the most
casual matters of geography and history to the profoundest laws of
atomic physics or even of pure mathematics and logic, is a manmade fabric which impinges on experience only along the edges.
• The field whose boundary conditions are experience
Logic
• Everything is in principle revisable--the difference between “logical
Scientific
Theories
principles” and empirical
claims
concerns the costs of revision
• Physical objects as “posits” (like Homeric gods)
Ordinary Empirical Claims
Ontology (again)
• What we admit to our ontology is a matter of what we need for the
best scientific theory
• Physical objects?
• Sets? Sets of sets?
• Brick houses on
Elm street?
Quine’s radical pragmatism
• When it comes to ontology everything is negotiable: Ontological
decisions are a matter of cost-benefit analysis reflecting on the
needs of science--an extension of common sense.
• Shift questions of ontology in the direction of pragmatism
– The “correct” ontology is the one that best serves the purposes
of the best science
– If science progresses so that the best science requires a
different ontology then we adopt a different ontology.
The Naturalization of Philosophy
Ontological questions…are on a par with questions of natural
science…the issue over there being classes seems more a
question of convenient conceptual scheme; the issue over there
being centaurs, or brick houses on Elm Street, seems more a
question of fact. But I have been urging that this difference is only
one of degree, and that it turns upon our vaguely pragmatic
inclination to adjust one strand of the fabric of science rather than
another in accommodating some particular recalcitrant
experience. Conservatism figures in such choices, and so does
the quest for simplicity…Each man is given a scientific heritage
plus a continuing barrage of sensory stimulation; and the
considerations which guide him in warping his scientific heritage to
fit his continuing sensory promptings are, where rational,
pragmatic.
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