Kant’s Schematism and Time Determinations by Rosie Hill

Within the Critique of Pure Reason, time and space are two of the most important concepts. By Kant’s account, they are the fundamental structures which allow us to experience the world the way we do. Time is the condition of our inner experience, and space is the condition of our outer experience. In the section, ‘Of the Schematism of the Pure Concepts of the Understanding’, Kant seems to temporarily abandon space as the transcendental schematism requires only our inner intuition, and so only time is necessary. I will evaluate Kant’s claim that the categories must be schematised as time determinations in order to apply to experience. First I will look at an overview of the Schematism, and why Kant believed it was necessary to introduce a third mediating factor between the categories and appearances. Then I will explain what a schema is, and why it is related to time. I will then briefly look at the schema of each category, and why Kant believes they are schematised as time determinations in this way. Then I will give some of my own criticisms of this view, and point out what I think may be some problems within the Schematism.

The problem that Kant wants to address in the schematism is how the categories can be applied to outer appearances, if the categories are entirely intellectual and the appearances are entirely empirical. This is problematic because, “in subsuming an object under a concept, the representation of the former must always be homogeneous with the latter” (B176/A137), but the categories cannot be homogeneous with appearances. To solve this problem, “there must be some third thing, which must be homogeneous on the one side with the category, and on the other with the appearance, and which thus renders the application of the former to the latter possible” (B176-177/A137-138). This mediating representation is the transcendental schema. The transcendental schema must also be a priori, as it is a part of our mind which relates to the fundamental possibility of our experience.

The schematism is a process which occurs within the imagination. It is important to note firstly that the schema of an object is not just an image of this object created by the imagination, because an image is particular and so cannot give us a general concept. Instead, the schema is the process in which the imagination is able to produce an image at all. In other words, it is how we can recognise that a specific object is a part of a larger set of objects, even when that larger set may only share a few common features with the object in front of us. For example, a palm tree and a maple tree look quite different from each other, however they share common features with each other which we associate with trees in general, such as a trunk, leaves, roots and so on, and so we can recognise both of these objects as trees. The schema is the process that allows us to use the categories to identify these particular aspects of an object in experience, and then subsume them under a more general concept. This also allows the schema to be a priori, as it is a fundamental process of the imagination, rather than an image found from experience.

Each schemata is a transcendental time determination. Time, unlike space, is homogeneous with both the categories and appearances, because as the form of inner sense, “time is the immediate condition of inner appearances, and thereby the mediate condition also of outer appearances” (B51-52/A35). This is because all representations are intuited internally, even if the object being represented is an outer appearance. In Kant’s words, “time is the formal condition, a priori, of all appearances whatsoever. Space, as the pure form of all external intuition, is a condition, a priori, of external phenomena only” (B50/A34). This is Kant’s reasoning for why each category must be schematised as a time determination, rather than a space determination. Another way to look at this is going back to the imagination, which as a form of inner intuition must be determined by time (B181-182/A142-143). Each category has its own transcendental schema. In looking at these schema, it will become clearer what a time determination is.

Starting with quantity, all categories have the same schema of number. This representation requires the “successive addition of one to one (homogeneous) other” (B181-182/A142-143). When we add parts together, we get the “unity of the synthesis of the manifold of a homogeneous intuition in general,” (B181-182/A142-143). By my understanding, this schema is the process of unifying a representation by adding intuited parts together to form a concept. Kant believes this is a time determination because this unity of parts only exists because, “I myself produce time in the apprehension of intuition” (B181-182/A142-143). When we are intuiting an object, we think of all its parts in one time, which allows us to unify it into one concept. Note that Kant speaks only of unity and not plurality or totality when describing the schema.

Moving on to quality, Kant again designates only one schema for each of these categories. This is the schema of reality. Kant suggests that these categories represent a scale of magnitude of sensation, which relates to the degree to which a representation of an object fills time. Kant states that there is a uniform transition from reality to negation (B183/A144). This seems to represent the vividness of an intuition at a certain time. For example, if we are feeling the sensation of pain somewhere on our body, then this sensation could have a certain degree of magnitude at any given time. So if the pain is very intense, it could fill our reality almost completely, and then if the pain eventually lessened to nothing, we would feel the absence of pain. In between these two times, we would feel each stage of the uniform transition between the two extremes. In this sense, quality represents how vivid or intense our experience of different sensations are at one point in time.

Each of the categories of relation and modality have their own individual schema. The schema of substance is permanence. Substance persists through time, and so gives us a permanent basis to relate objects through time. The permanence of substance allows us to understand things as changing, rather than appearing and disappearing from existence, and also allows us to recognise different objects through time. The schema of causality is succession. That is, one thing always succeeds another, and this must be determined by a rule. Finally, the schema of community is simultaneity, or the necessary simultaneity of reciprocal causal interaction. Moving onto the categories of modality, the schema of possibility is existence at some time, the schema of actuality is existence at a determinate time, and the schema of necessity is existence at all times (B184-185/A145-146). For the categories of relation and modality, their determination in time through the schematism seems more obvious, and they seem to be more related to time than the categories of quantity and quality.

This leads to my criticism of Kant’s schematism. It seems strange that although Kant is usually so thorough in his descriptions, each of the categories of quantity and quality have the same schema, whereas the categories of relation and modality have their own individually. The schema of these latter two groups of categories also seem to be more obviously determined in time than the first two. Perhaps the first two sets of categories would be better understood as determined in space rather than time. For quantity, Kant asserts that schema leads to the “production (synthesis) of time itself, in successive apprehension of an object” (B184-184/A145-146). This suggests that the schema of unity would be the apprehension of an object at one time, plurality would be the apprehension of an object at multiple times, and totality would be the apprehension of an object at all times. This does not seem to be the correct way to think of quantity however, and it seems more accurate that the category of substance, with its schema of permanence, or the different schemas of the categories of modality would fill this role better. Similarly with quality, Kant does not speak of the vividness of sensation over time, or at different times, but the degree of which a sensation fills our perception at one time. This schema seems to be more about the manifold of our intuitions at one time, and how we intuit different degrees of sensation within space as outer experience, not over time.

If we allowed the categories to also be schematised as space determinations, then this would imply that space is homogeneous with both the categories and appearances. Kant believes that as the form of outer intuition, space is homogeneous with appearances only. As discussed above, Kant believes that time is the mediate condition of outer appearances because we intuit representations of objects internally, and so all our relations of objects are internal and are thus in time (B51-52/A35). Is it possible for space to also be a form of inner intuition? Of course, an indeterminate concept is not placed in space, however, images within the imagination could be argued to occupy a form of inner space. We cannot have an image of an object, without regarding it as somehow occupying space, in fact space seems to be part of the form of images in general. As the schematism is the process of producing an image from a concept within the imagination, if the image contains space, then space must be some part of this process of schematising.

This relies on space existing within our minds in some sense, as grounding for images of the imagination. This is debatable, however, I think that considering Kant’s description of space as a structure within the mind, it is not unthinkable that perhaps this is true, and space is also a part of inner experience in the same way that time is. Perhaps to reverse the position posited by Kant, space may be the mediate representation of inner sense. But does this mean that space is homogeneous with the categories? Considering that the categories are merely structures of our mind that allow us to understand the world of appearances, it seems that if space has a place within our mind, then it could be homogeneous with the categories. In other words, perhaps it is both time and space that connect the categories and appearances, and which allow objects to be subsumed under concepts. This is only one solution to the problem, and unfortunately it does change Kant’s fundamental structures of our experience, which underpins much of the Critique of Pure Reason, so there may be a better solution.

Kant’s schematism is an important part of the critique, and I think that overall it is successful in connecting the purely intellectual categories, and purely sensible appearances via the imagination. I also think that the schematism is an essential part of the structure of the mind, as it seems that there does need to be some process in the imagination which links the objects of experience to concepts within our mind. Despite this, I feel that there is a problem with schematising the categories purely as time determinations rather than space determinations in order to apply them to outer appearances. I think that this is seen through there being only one schema which relates to each of the categories within in quantity, and the same for quality. It seems that for these two groups of categories, it might make more sense to link the categories and appearances through space rather than time. To do this, it may be possible to think of space as homogeneous with concepts, but even if this fails, I still think there may be a problem with Kant’s idea of schematising the categories purely via time determinations which should be solved in some other way. I do not think this problem undoes the Schematism, but instead allows room for more clarity.

Rosie Hill is a UQ student studying a dual Bachelor of Science and Arts.



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Photo by Eder Pozo Pérez.

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