Roxanna Anderson

I defend Kant’s definition of analyticity in terms of concept “containment”, which has engendered widespread scepticism. Kant deployed a clear, technical notion of containment based on ideas standard within traditional logic, notably genus/species hierarchies formed via logical division. Kant’s analytic/synthetic distinction thereby undermines the logico-metaphysical system of Christian Wolff, showing that the Wolffian paradigm lacks the expressive power even to represent essential knowledge, including elementary mathematics, and so cannot provide an adequate system of philosophy. The results clarify the extent to which analyticity sensu Kant can illuminate the problem of a priori knowledge generally.

Martin offers an intriguing account of nineteenth century challenges to the traditional theory of judgment as a synthesis of subject and predicate (the synthesis theory)--criticisms motivated largely by the problem posed by existential judgments, which need not have two terms at all. Such judgments led to a theory of "thetic" judgments, whose essential feature is to "posit" something, rather than to combine terms (as in synthetic judgment). I argue, however, that Kant's official definition of judgment already implicitly recognizes the importance of positing, and that its (otherwise confusing) abstract generality actually affords Kant's own logic an adequate way to accommodate existential judgments within the traditional synthesis theory. Preservation of a synthetic account of judgment is also found to be independently important for Kant's larger aims in the theory of cognition.

One of the central and most distinctive theses of Kant’s philosophy of mathematics is that mathematical knowledge is synthetic. In this context, synthetic judgments are defined in opposition to analytic ones, whose predicate concept is “contained in” the subject. Kant’s thesis has often been attacked as indefensible, but just as frequently critics have complained that the thesis itself, and even the analytic/synthetic distinction on which it rests, are simply unintelligible. Thus, even prior to questions of its correctness, the Kantian doctrine has been rejected as unclear, based on general skepticism that there is a real distinction of “containment”—or indeed any tolerably clear distinction at all—between analytic and synthetic judgments.

Officially, for Kant, judgments are analytic iff the predicate is "contained in" the subject. I defend the containment definition against the common charge of obscurity, and argue that arithmetic cannot be analytic, in the resulting sense. My account deploys two traditional logical notions: logical division and concept hierarchies. Division separates a genus concept into exclusive, exhaustive species. Repeated divisions generate a hierarchy, in which lower species are derived from their genus, by adding differentia(e). Hierarchies afford a straightforward sense of containment: genera are contained in the species formed from them. Kant's thesis then amounts to the claim that no concept hierarchy conforming to division rules can express truths like '7+5=12.' Kant is correct. Operation concepts ( ) bear two relations to number concepts: and are inputs, is output. To capture both relations, hierarchies must posit overlaps between concepts that violate the exclusion rule. Thus, such truths are synthetic.