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Ivan Di Liberti (Oct 07 2025 at 20:40):I just came across this paper, of which I will copy paste the abstract below.
Kant considers his Critique of Pure Reason to be founded on the act of judging and the different forms of judgement, hence, take pride of place in his argumentation. The consensus view is that this aspect of the Critique of Pure Reason is a failure because Kant’s logic is far too weak to bear such a weight. Here we show that the consensus view is mistaken and that Kant’s logic should be identified with geometric logic, a fragment of intuitionistic logic of great foundational significance.
These days I do not have much time to read it, so I cannot make any assessment about it, but maybe someone in the community has a comment? I would be curious.
Jean-Baptiste Vienney (Oct 08 2025 at 00:30):All I can say is that Peirce’s logic has been revisited in light of categorical logic too (and this is based on real math papers!): Modernizing Peirce’s Existential Graphs (paper by @Nathan Haydon). So, now, I’m less surprised to read that Kant’s logic seems to be the same as geometric logic.
Kevin Carlson (Oct 08 2025 at 01:11):I glanced at it, seems cool, but it seems impossible to assess for anybody who hasn't already read the Critique. Sadly, as David McCarty predicted when I did not sign up for a course in it during undergraduate, I continue to be excluded from that anointed few.
David Corfield (Oct 08 2025 at 08:34):The path that leads from Kant to Martin-Löf, via Lotze, Husserl and others, is an interesting one, with its much greater stress on the intricate structure of the act of judgement.
Peirce took there to be greater logical content in Kant's Critique than what we now might consider as a logic.
Kant's Four Classes of Categories
Peirce was looking to integrate (4) by developing his gamma system of existential graphs, but it was far from finished when he died,
Jencel Panic (Oct 15 2025 at 08:39):Not related to the paper (I think), but I always thought that the quality triad is a direct correspondence of the intuitionistic logic:
Kant writes
For example, if I say of the soul, “It is not mortal”—by this negative judgment I should at least ward off error. Now, by the proposition, “The soul is non-mortal,” I have, in respect of the logical form, really affirmed, inasmuch as I thereby place the soul in the unlimited sphere of immortal beings. Now, because of the whole sphere of possible existences, the mortal occupies one part, and the immortal the other, neither more nor less is affirmed by the proposition than that the soul is one among the infinite multitude of things which remain over, when I take away the whole mortal part.