If one agrees with Quine's dissolution of the Analytic/Synthetic distinction, what is left of Kant's epistemology?

Question

One of Kant's most important (if not the most important) result is his argument (proof?) that synthetic a priori knowledge is possible.

If one agrees with Quine's argument against Analyticity as being circular and the subsequent dissolution of the Analytic/Synthetic distinction, what is left of Kant's epistemology?

My understanding is that if Quine's result from Two Dogmas holds, then everything is to some extent synthetic and nothing is really a priori. Is this interpretation correct?

Can one preserve his notion of synthetic apriori (or any form of rationalist epistemology) in the face of Quine's critique?

Answer 1

Recall that to Kant since Aristotle "logic has not been able to advance a single step, and is thus to all appearance a closed and completed body of doctrine" (Critique of Pure Reason): no propositional variables, no connectives, no multi-place predicates, and no quantifiers. So Kant's notion of analytic is so impoverished that he would not lose much by simply accepting that everything, including logic, is synthetic. After all, he already declared that mathematics is synthetic. But it is also a priori, which means that synthetic is compatible with a priori. Moreover, some pragmatic shadow of analyticity is preserved even by late Quine of Two Dogmas in Retrospect:

"Analyticity undeniably has a place at a common-sense level, and this has made readers regard my reservations as unreasonable. My threadbare bachelor example is one of many undebatable cases... In Roots of Reference I proposed a rough theoretical definition of analyticity to fit these familiar sorts of cases. A sentence is analytic for a native speaker, I suggested, if he learned the truth of the sentence by learning the use of one or more of its words. This obviously works for 'No bachelor is married' and the like, and it also works for the basic laws of logic."

A much more serious revision of Kant is not Quine's dissolution of the analytic/synthetic distinction but rather his epistemological holism, including the denial that anything is a priori. This he also moderated in late years, although not on principle:

"Looking back on it, one thing I regret is my needlessly strong statement of holism... "no statement is immune to revision". This is true enough in a legalistic sort of way, but it diverts attention from what is more to the point: the varying degrees of proximity to observation..."

But on this score we have a response from a modern neo-Kantian, Michael Friedman, and his theory of relativized a priori (anticipated already by logical positivists, like Reichenbach), see What are the more complex/interesting examples of synthetic a priori statements? and Are there necessary truths in physical theories, more or less strictly speaking?

It is a natural conciliation of Quine with Kant which admits that yes, everything is empirically revisable, but no, theoretical knowledge is more structured than an undifferentiated "web of belief" with its parts differing only by being more or less "entrenched". Certain "philosophical meta-principles" (like locality, causality, etc.), and "coordination principles" (connecting theories to observations) must be assumed in advance to even enable empirical measurements and their interpretation. They can not therefore be tested empirically in any straightforward sense, nor do they come from any kind of empirical induction, they are a priori and rational in origin. But they are not absolute, as Kant thought, for they can be adopted or abandoned based on the overall success of a paradigm (this is Friedman's infusion of Kuhn into Quine), judged in a loosely empirical manner, like classical determinism or Euclidean geometry were. Here is the gist of Friedman's argument against Quine's holism in Dynamics of Reason:

"Quine's epistemological holism pictures our total system of science as a vast web or conjunction of beliefs which face the "tribunal of experience" as a corporate body... But can this beguiling form of epistemological holism really do justice to the revolutionary developments within both mathematics and natural science that have led up to it? Let us first consider the Newtonian revolution that produced the beginnings of mathematical physics as we know it - the very revolution, as we have seen, Kant's original conception of synthetic a priori knowledge was intended to address.

"The combination of calculus plus the laws of motion is not happily viewed... as a conjunction of elements symmetrically contributing to a single total result. For one element of a conjunction can always be dropped while the second remains with its meaning and truth-value intact... the mathematics of the calculus does not function simply as one more element in a larger conjunction, but rather as a necessary presupposition without which the rest of the putative conjunction has no meaning or truth-value at all. The mathematical part of Newton's theory therefore supplies elements of the language or conceptual framework, we might say, within which the rest of the theory is then formulated.

Incidentally, this allows Friedman to resurrect the analytic/synthetic distinction as well, but not in the Carnapian form attacked by Quine ("I have no desire to defend Carnap's particular way of articulating this distinction here"). Rather than distinguishing different sentences within a theory as analytic or synthetic, he proposes a meta-distinction between theories and their presuppositions.

Answer 2

Singling out Quine, in the context of Kant's synthetic apriori, seems to me out of place. There was nothing special about Quine's attitude towards Kant's synthetic apriori. Quine's specialty was his criticism of the analytic apriori, and this in turn has no special relation to Kant. Kant's synthetic apriori had some following during the 19th century. But by the dawn of the 20th century, practically nobody accepted the synthetic apriori. So Quine is really not special, and is therefore not the issue here.

At least one aspect of Kant's epistemology has remained alive, however. It is the thesis that some parts of what we take to be knowledge are constitutive rather than merely descriptive. These parts make the form, and not merely the content, of what we seem to know. The constitution thesis can be separated from the apriority thesis (that is, absolute immunity to experience) which has become obsolete.

One useful simile, provided by the later Wittgenstein in On Certainty, while discussing the epistemological status of logic, is the distinction between the water of a river, and the river bed. Constitutive knowledge is like the river bed. The river bed can, and does, change in time (and is therefore not strictly apriori). But it has a deeply different kind of dynamic than that of the river's water.

97. The mythology may change back into a state of flux, the river-bed of thoughts may shift. But I distinguish between the movement of the waters on the river-bed and the shift of the bed itself; though there is not a sharp division of the one from the other.

98. But if someone were to say "So logic too is an empirical science" he would be wrong. Yet this is right: the same proposition may get treated at one time as something to test by experience, at another as a rule of testing.