Kohl, M. (2015): Kant on the inapplicability of the categories to things in themselves

PDF Link

The Argument (91)

  1. Noumena have categorial properties (i.e. the properties that we represent through the pure categories) only if an intuitive, divine intellect would represent them as having such properties.
  2. An intuitive intellect would not represent noumena as having categorial properties.
  3. \(\therefore\) Noumena do not have categorial properties.

Principles supporting 1 & 2

Principle P:
how an intellect would represent things is the one decisive measure for what things are in themselves (and, a fortiori, for whether or not things in themselves possess categorial properties)
Principle O:
only the representations of an intuitive intellect would provide cognizance of things in themselves.
Principle C:
an intuitive intellect would have a complete maximum of cognition: it would cognize every property of every thing in itself.

Categorial features are not in things themselves

The Ambiguity Hypothesis:
While a non-discursive intellect would not employ our (or, indeed, any) concepts (categories), it would know that noumena exhibit those features (SUBSTANTIALITY etc.) that we also think through these concepts (97)

Kohl argues that the categories represent only ‘purely discursive features’, which are “properties that wholly depend on a discursive manner of representation” (98-9).

Kohl presents three reasons for endorsing the discursivity claim (99).


First, Kant states that the pure categories ‘contain exclusively [allein] the synthetic unity of apperception’ (B148; cf. A119; A138/B177)

Since the pure categories contain exclusively the abstract form of the synthesis that constitutes appearances, they ‘serve only to spell [buchstabieren] appearances’ (AA4: 312)

It isn’t totally clear to me what the argument is here. But the basic idea seems to be that the categories have no content beyond that necessary for a unitary consciousness of empirical objects. So there is nothing “in” the content of the categories that could be applied to non-sensible objects. But this is question-begging.


Kant states that in the unschematized categories ‘nothing can be found other than the mere form of thought’ (A567/B595; cf. A50–51/B75; B288).


This form could not enter into the representation of an intuiting understanding that does not think (B71–72; AA8: 399; AA28: 42).

While it is trivially true that a non-discursive being would not represent anything using the forms of thought, this doesn’t show that a non-discursive intellect would not represent, de re, anything that we discursively represent.


Kant states that the pure category ‘can contain nothing but the logical function to bring the manifold under a concept’ (A245).

I’m not sure how this differs from the second point. But,

Since this is the entire possible content of the pure categories, it follows that an intuitive intellect, which would not bring manifolds under concepts, would not represent what we think in the pure categories.

Again, there is a slide from ‘would use a different manner of representation’ to ‘would represent a different thing’. That isn’t justified.

Perhaps Kohl’s best argument (and this is Hegel’s argument) is that Kant empahsizes that the categories, like the forms of intuition, are features of our mind, and not features of the things themselves.

Kant insists that the pure categories are ‘merely subjective forms of the unity of understanding’ (A287/B344; cf. A567/B595), ‘nothing but’ logical functions for combining given manifolds (A245; AA4: 324). These characterizations echo Kant’s claims about space and time: these are ‘nothing but’ (A42/B59; A33/B49; A492/B520), ‘merely’ (A48/B66) ‘subjective condition[s] of sensibility’ (A26/B42), ‘mere form[s] of … intuition’ (A48/ B66).

Though, again here Kohl slides from the issue of cognition to that of representation. Kant indeed denies that the categories can be applied beyond the bounds of sense to provide cognition of any thing in itself. But this doesn’t show that the categories cannot represent any thing in itself. In this way Kohl’s argument is guilty of the very same kind of error that various folks have discussed with respect to Hegel’s indictment of Kant’s subjectivism.

Icon by Nun from The Noun Project. Website built with Org-mode, Hugo, and Netlify.