The sum of the above is this: the business of the senses is to intuit, that of the understanding to think. But to think is to unite presentations in a consciousness. This union is either merely relative to the subject, and is contingent and subjective, or is given unconditionally, and is necessary or objective. The union of presentations in a consciousness is judgment. Thinking, then, is the same as judging, or referring presentations to judgments in general. Hence judgments are either entirely subjective when presentations are solely referred to a consciousness in one subject, and are therein united, or they are objective when they are united in a consciousness in general, that is, are necessarily united therein. The logical momenta of all judgments are so many possible modes of uniting presentations in a consciousness. But if they serve as conceptions, they are conceptions of the necessary union of the same in a consciousness, and therefore principles of objectively valid judgments. This union in a consciousness is either analytic by identity, or synthetic by the combination and addition of different presentations to one another. Experience consists in the synthetic connection of phenomena (perceptions) in a consciousness, in so far as this is necessary. Hence pure conceptions of the understanding are those under which all perceptions must be previously subsumed, before they can serve as judgments of experience, in which the synthetic unity of perceptions is presented as necessary and universal.
Before going forward, it’s important to make sure we have the basic terminology in hand: Sensibility The faculty of the mind that ‘receives’ intuitions
Intuition(Anschauung)A bit of sensory awareness. This can refer to any kind of sensory awareness, from any sense modality whatsoever, as well as those bits of awareness that are also called up by the memory.
All intuitions are in time (as objects of thought, they always occur in temporal positions relative to each other); some of these are also in space (that is, they represent their objects as having spatial location). Time is the form of inner intu- ition; space, outer intuition.
The matter of an intuition is its purely sensory element—in visual images, for example, this would include color. Its formis the spatial or temporal structure the sensibility imposes on this ‘matter.’ So even in sensation the mind is not purely passive—it is actively structuring its perceptions.
UnderstandingThe faculty that unites intuitions into thoughts
Sensibility generates intuitions; the understanding generates concepts.But how can we bring these together?Intuitions without concepts are blind; concepts without intuitions are empty.Howare the two going to be united?
JudgmentThe basic unit of thought, in which the mind unites distinct intuitions into a coherent whole. All judgments are judgments of perception; some judgments are also judgments of experience. The basic unit of thought, as opposed to sensibility, then, is the proposition: a claim that things are thus-and-so.
A judgment of perceptionunites intuitions merely according to the logical forms of judgment (page 600, Section 21). These judgments only have subjective validity; that is, they make a claim only about the perceptions of the person doing the judging. In a JOP, I “merely compare perceptions and connect them in a consciousness of my state” (599).
Example: when I say, ‘if I perceive gold being immersed in aquaregia, I then perceive its dissolution,’ I have not said anything about whether this must happen, will happen in all cases, or, most importantly, why it happens. I have only made a report about my own perceptions. Or: suppose I conjure up an image of a dagger. I can unite these intuitions according to the mere form of judgment and bring together the perceptions of the handle and the blade. But I don’t think of the dagger as a real object that others would see if they were here and could use to open their mail.
A judgment of experience, by contrast, unites intuitions according to the logical forms of judgment and the pure concepts of the understanding, the categories. When I say that putting gold in aqua regia causes it to dissolve, I am not merely saying that the one perception follows the other. I am saying that this happens necessarily, i.e., that it happens according to a law of nature. My claim is objectively valid: that is, I am claiming that anyone similarly situated will observe exactly what I observe when I dropped the gold into the solution. (Objective validity is a necessary, but not sufficient, condition for truth. An objectively valid judgment is a candidate for being true; it is not automatically so. See the CPR, A58/B83).
“Experience consists in the synthetic connection of appearances in consciousness, so far as this connection is necessary.” Thinking of this connection as necessary and as holding for all similarly situated cognitive beings requires the categories, pure concepts of the understanding that structure our intuitions into experience. Concepts of any kind are always rules for making judgments. The concept dog, for example, is a rule that tells you which of your intuitions to unite so you can come to think of those intuitions as a single thing, viz., a dog. So the categories are the maximally general rules we use to generate experience. (Imagine what your ‘experience’ would be like if you lacked these pure concepts.)
Sensibility imposes a form on the material element of sensation and generates an intuition; in parallel fashion, the understanding imposes a form on intuitions and generates experience.
Section Twenty-two: The Second Part, Continued above presents a clear summary of Kant’s argument so far. Here is one way to sketch it; I encourage you to try your own.
- We have experience (in the weighty sense), not just a flood of intuitions (what sensibility provides) and not just a set of thoughts about our mental states (JOPs).
- Experience is possible only if we unite intuitions in propositions.
- Only judgment can unite these intuitions.
- To do more than think about our own mental states (JOPs), we have to use certain concepts.
- These concepts allow us to unite our intuitions in propositions that, if true at all, are true for all possible subjects of experience. They involve a necessary connection between the objects of my intuitions, not merely the connection of intuitions in my own private experience.
- These concepts must be synthetic and apriori.