Kant shows in the Critique of Pure reason that there are multiple categories and he uses logic to come to these conclusions.
“The same function that gives unity to the different representations in a judgment also gives unity to the mere synthesis of different representations in an intuition, which, expressed generally, is called the pure concept of understanding. The same understanding, therefore, and indeed by means of the very same actions through which it brings the logical form of a judgment into concepts by means of the analytical unity, also brings a transcendental content into its representations by means of the synthetic unity of the manifold in intuition in general, on account of which they are called pure concepts of the understanding that pertain to objects a priori; this can never be accomplished by universal logic.” (A79, B105)
This paragraph is supposed to be the possible key to understanding the argument for the deduction of the categories, and is often referred to as the metaphysical deduction of the categories. Kant attempts to use the forms of logical judgment to deduce the forms of cognitions in general. The passage contains just two sentences, but is nearly unapproachable, even at the level of individual clauses, especially when compared to his earlier work in Transcendental Deduction. However, it does contain an important step in the argument of the critique, one that not only allows Kant to move between the table of judgments and the table of categories, but also that indicates the transcendental role of the understanding; the way in which intellectual conditions operate to allow the possibility of experience, made obvious by an examination of logic.
The ‘pure concept of understanding’ plays a fundamental role in this argument, but unfortunately it is not obvious what the term refers to. One can temporarily think of it as referring to the faculty of understanding and not solely one or more of the wholesome concepts of the understanding. The main interpretive predicament of this passage revolves around the term “transcendental content.” It may be the case that Kant wants to differentiate the Transcendental Logic’s possession of objective content with general logic’s lack of content. However, the term could also refer to the fact that the understanding has a transcendental function, and could be indicating the transcendental nature of the categories. Each of these interpretations will be evaluated in turn. This information allows one to form substance from the category of judgment or cause from the category of hypotheticals.
The Argument is that at its most basic, with all the explanatory clauses removed from the argument it appear through the following points. 1. The understanding gives unity to different representations of a judgment. 2. It also gives unity to the synthesis of representations in an intuition. 3 The understanding brings transcendental content to its...