The Categories and “Kantian Modality”

So far I have focused on what Kant has to say about each particular modal concept, and brought out an account in terms of propositions being compat- ible with or a consequence of conditions on possible experience. Alternative approaches to understanding Kant on modality focus on his account of con- cepts, and in particular pure concepts of the understanding, i.e. categories. In this section I consider how one might understand Kant’s notion of a cat- egory, and the kinds of conclusions that have been drawn from the thesis that modal concepts are categories. Finally, I assess how this understanding of “Kantian Modality” can be best integrated with the relative account that has emerged so far.

The categories are concepts that must be applied in experience in order for us to experience the world as we do. These concepts are not acquired from experience, but are prerequisites for experience. Kant thus also calls them a priori concepts, as opposed to empirical concepts. Kant is also famous for his transcendental idealism. One way to understand transcendental idealism is as the thesis that humans (and similarly-minded creatures) can only have experience of appearances, and not of things-in-themselves. Our minds are such that there are certain a priori constraints on how we experience things. Appearances are shaped by these constraints, e.g., space and time are forms imposed upon the world by us. The world we experience, the empirical world investigated by science, is a world of appearances. Transcendental idealism is contrasted with transcendental realism, the view that we can experience things-in-themselves directly.

Philosophers often get nervous when transcendental idealism is men- tioned. Lots of difficult questions concerning the nature of appearances and things-in-themselves, and how we are to interpret such a distinction, are in- evitably raised. But it is wrong to think that in order to profit from some of Kant’s ideas, we are always required to pay the admission price of defending transcendental idealism. For a start, that would involve a potentially endless

digression, and we wouldn’t make any progress on other, potentially more fruitful, aspects of Kant’s work. What I want to do, as far as possible, is to set transcendental idealism to one side, and focus on some of the aspects of Kant’s view that are more obviously related to what he has to say about modal concepts. The modal concepts are taken by Kant to be categories, so one such aspect of Kant’s view to be considered is the notion of a category, and how that can be made sense of independently of an obvious commitment to transcendental idealism.

One may wish to hold on to the idea that certain concepts or features are somehow fundamental to human experience, or a priori in some sense, without having to be a full-blown transcendental idealist. Strawson has offered an alternative to the “transcendental idealist interpretation” of a priori concepts, the “austere interpretation”.

In the first, or austere, interpretation a concept or feature (el- ement) could be called a priori if it was an essential structural element in any conception of experience which we could make intelligible to ourselves. In the second, or transcendental ideal- ist, interpretation to call an element a priori was to claim that its presence as a feature of experience was attributable entirely to the nature of our cognitive constitution and not at all to the nature of those things, as they are in themselves, which affect that constitution to yield experience. (Strawson, 1966, p. 68)

Concepts can be understood as a priori by making reference to conceptions of experience. This is in contrast to an interpretation which relies on making reference to cognitive constitution and to “things-in-themselves”. The for- mer interpretation thus avoids both having to make specific psychological claims about our cognitive make-up, and having to engage in speculative metaphysics concerning these odd “things-in-themselves”, and what role they might play in determining various aspects of our experience.

To show that a concept or feature was a priori in Strawson’s austere sense would involve having to show that this concept or feature was in- deed essential to any intelligible conception of experience. In The Bounds of Sense, Strawson lists what he thinks are the main theses Kant puts forward regarding essential features of experience, i.e. ‘what the limiting features must be of any notion of experience which we can make intelligible to our- selves’ (1966, p. 24).

1. The temporality thesis: experience essentially exhibits temporal suc- cession.

2. The thesis of the necessary unity of consciousness: there must be such unity among the members of some temporally extended series of experiences as is required for the possibility of self-consciousness, or

self-ascription of experiences, on the part of a subject of such experi- ences.

3. The thesis of objectivity: experience must include awareness of objects which are distinguishable from experiences of them in the sense that judgments about these objects are judgments about what is the case ir- respective of the actual occurrence of particular subjective experiences of them.

4. The spatiality thesis: the objects referred to in (3) are essentially spa- tial.

5. The thesis of spatio-temporal unity: there must be one unified (spatio- temporal) framework of empirical reality embracing all experience and its objects.

6. The theses of the Analogies: certain principles of permanence and causality must be satisfied in the physical or objective world of things in space. (See Strawson (1966, p. 24))

Each thesis is clearly a significant issue in its own right. E.g., issues con- cerning whether experience has to involve temporal succession, or whether temporal succession and extension in experience is a necessary condition for self-consciousness, have been widely discussed and form a significant topic for debate in their own right, with a rich philosophical history. (See Brentano (1913ff), Russell (1913), Stout (1930), and more recently, Kelly (2005a,b), Dainton (2000) and many others.) It can be seen that to engage with even one of these theses is a significant task, let alone all of them.

Strawson goes on to assess which, if any, of these theses can be upheld, and the kinds of arguments required. Someone wanting to uphold the the- sis that modal concepts are categories might follow Strawson’s lead. One version of a Kantian account of modality might claim that any notion of experience which we can make intelligible to ourselves will include modal elements and argue accordingly. I will not pursue this in detail here, but will offer a brief suggestion of ways to argue for this kind of claim.

Keeping closely in line with Kant, one might argue that our application of modal concepts to experience is required for and embodies that unity of consciousness which makes any experience possible at all.

In the Deduction we find a repeated insistence that a certain connectedness and unity among our experiences is necessary to constitute them experiences of an objective and law-governed world; that the concepts of the object which we apply in experi- ence embody the rules of such unity; and that this rule-governed connexion of experiences under concepts of the objective is pre- cisely what is required for the necessary unity of consciousness,

i.e. for the possibility of self-consciousness. (Strawson, 1966, pp. 26–7)

There are two ways one might to try to develop the idea that modal concepts are categories in this way, i.e. that modal concepts are required to contribute to the unity of experience. First, one might argue that “things being modal” or “things being modally related” is a necessary feature of a unified world of experience, this being achieved by our applying modal concepts to the world. Take causation: perhaps the idea that events are causally related is a necessary one for any unity in experience, otherwise we could not link different experienced events in an orderly manner. Therefore, causation is an essential feature of experience, without which there would be no unity of experience, nor unity of consciousness. It is not clear how modal concepts such as real possibility and necessity could be argued to play this role.

An alternative way to develop this idea is to go deeper and argue that the rule-like nature of the concepts which embody this necessary unity is a modal matter, and so modality is built right into the foundations of con- ceptualized human experience, in the modal nature of concepts themselves. E.g., perhaps the concept of causation embodies the unity of experience, but possession of any concept at all, including the concept of causation, re- quires some ability to think modally. Brandom (2008) and Baldwin (2002) each have arguments for the view that concept-possession and our reasoning practices are inescapably modal. The conclusion is that modality is an in- escapable feature of conceptual thought and inference. Combined with the assumption that concept-possession and/or reasoning practices are essential to human experience, these arguments can be used to mount an argument for modality being an inescapable feature of human experience. At least they purport to show that the cognitive resources required for the making of modal judgments, or the possession of modal concepts, are requirements for any kind of concept possession at all.

The arguments from Brandom and Baldwin are rather similar, and both take Kant to be their source. Brandom discusses what he calls “the modal Kant-Sellars thesis”, comprised of two claims:

1. In using ordinary empirical vocabulary, one already knows how to do everything one needs to know how to do in order to introduce and deploy modal vocabulary.

2. The expressive role characteristic of alethic modal vocabulary is to make explicit semantic, conceptual connections and commitments that are already implicit in the use of ordinary empirical vocabulary. (Bran- dom, 2008, p. 102)

Brandom argues for the view that the practices and abilities which underlie the ability to deploy alethic modal vocabulary are practices and abilities

which are required to underlie the deployment of any empirical vocabulary at all. This is because the ability to understand the vocabulary (possess the requisite concepts) requires the ability to assess the robustness of material inferences in counterfactual situations involving those concepts, which in turn requires the ability to think counterfactually, i.e. modally. E.g.,

One grasps the claim “the lioness is hungry” only insofar as one takes it to have various consequences (which would be true if it were true) and rule out some others (which would not be true if it were true). And it is not intelligible that one should endorse as materially good an inference involving it, such as the inference from “the lioness is hungry” to “nearby prey animals visible to and accessible by the lioness are in danger of being eaten,” but be disposed to make no distinction at all between collateral premises that would, and those that would not, if true infirm the inference. One must make some distinction such as that the inference would still go through if the lioness were standing two inches to the East of her actual position, the day happened to be a Tuesday, or a small tree ten miles away cast its shadow over a beetle, but not if she were shot with a tranquilizing dart, the temperature instantly plummeted 300 degrees, or a plane crashed, crushing her. The claim is not that one could not fail to assess some or even all of these particular counterfactuals correctly and still count as grasping the claim that is their premise, but that one could not so qualify if one made no such distinctions. (Brandom, 2008, p. 105)

In other words, properly understanding a concept or a piece of vocabulary involves some grasp of the consequences of difference scenarios for instances of the concept. That grasp of consequences involves the ability to reason counterfactually. And the ability to reason counterfactually, or the practice of reasoning counterfactually, is sufficent to account for the introduction of modal vocabulary. This accounts for part 1 of the modal Kant-Sellars thesis, and presents one way to understand modal concepts as being an essential element of experience: any possession and use of concepts (any use of em- pirical vocabulary) relies on a prior grasp of modal concepts (vocabulary). Part 2 of the thesis goes on to claim that modal vocabulary is expressive, rather than descriptive.

Baldwin makes a similar claim, that possession of a concept requires the ability to apply it in possible as well as actual situations. This is cashed-out in terms of an ability to reason from the supposition that a certain concept applies in a possible situation.

I start from Kant’s thesis that concepts are rules for the un- derstanding whose application to experience requires that they

be also applicable by the imagination (A124–6). For this sug- gests that the ability to apply a concept correctly to observed actual situations requires the capacity to apply it in the course of deliberation concerning possible situations as well, and thus that there is a intrinsically modal aspect to the possession and use of concepts. But all this needs more elucidation. Concepts, on this account, are not simply capacities to respond accurately to types of observed phenomena by registering their presence. Their role in framing desires and intentions already shows an ability to apply them to what is thought of as nonactual. . . .

Yet although non-actuality is an ingredient of mere possi- bility, not everything non-actual is possible and more needs to be said to fill out the role of modality in characterising concept possession. We get closer to this, I think, by considering what is characteristic of the ability to understand what it would be for something to be both F and G. For the obvious account is that it involves an ability to reason concerning the implications, both positive and negative, of the hypothesis that something is both F and G, where the ability to identify these implications does not require knowledge of whether or not they actually obtain. This suggestion connects concept-possession with a capacity for reasoning, and this is, I think, the fundamental aspect of the matter. (Baldwin, 2002, pp. 9–10)

Like Brandom, Baldwin claims that modal abilities and practices inherent in reasoning underlie concept possession. Part of understanding a concept is being able to reason concerning the consequences for instances of the concept in different scenarios, and the interaction of the concept with others in such scenarios. This reasoning is where modality enters in. Insofar as we are conceptual creatures, these arguments purport to show that modality is an inescapable feature of our conceptual lives. We have a way to understand Kant’s notion of a modal category: a practice or ability necessary for any concept possession at all, which can be expressed in terms of further concepts (modal concepts).

The conclusion that modal concepts are (or the ability to think modally is) a prerequisite for conceptual thought and experience is all very well, but it does not yet say much about the nature of modality. Perhaps there are genuine, objective, mind-independent modal properties of things, perhaps even concrete, spatiotemporally and causally-isolated possible worlds, con- stituting modality in reality, and by happy coincidence our ability to possess and use concepts is underpinned by an ability to possess and use modal con- cepts which capture this aspect of reality. The second part of Brandom’s modal Kant-Sellars thesis claims that the role of modal vocabulary is to “make explicit” semantic and conceptual commitments and connections in

our use of ordinary empirical vocabulary, not to describe how things are modally in the world. Similarly, Baldwin develops his view by arguing that modal judgments are expressive of our norms of reasoning, which are the modal notions underlying our use of concepts. He notes that if modal judg- ments were just reports of modal connections between concepts, this would hardly be an improvement on an account where modal judgments are taken to be reports of modal connections between properties and objects.

For on this view,21 concepts come, like atoms, with an intrinsic modal ‘valency’ that enables them to join up with other concepts in the molecular patterns that our ordinary modal judgments capture. This would be a realist account of the matter; and the objection to it is that it seems not much less mysterious than the accounts of modality propounded by those who rely on Aristotelian essences or merely possible worlds. All that the conceptualist move has achieved is that the grounds for unease have been shifted by locating primitive modality at the level of sense (concepts) rather than at the level of reference (properties, worlds); but this does not remove the unease. (Baldwin, 2002, p. 12)

The idea is that such modal connections are no less mysterious for being between concepts rather than objects, but if we take modal judgments (i.e. judgments with apparent modal content) to be expressions (rather than descriptions) of our norms of reasoning with concepts, then we have an explanation of the source of our modal commitments and judgments, with- out having to explain these mysterious, objective, modal relations between things.

. . . the anti-realist . . . holds that modal judgment is the expres- sion of norms inherent in the capacity that we have to reason from our thoughts which is essential to our capacity to have thoughts at all. (Baldwin, 2002, p. 13)

E.g., the anti-realist might take a judgment that necessarily, all bachelors are unmarried, to be an expression of norms inherent in the capacity to reason using the concepts bachelor and unmarried, norms which are essential to our capacity to have thoughts using these concepts at all.

To discuss the pros and cons of such a view is too great a task for present purposes. The pertinent question here is how far this view is an accurate reflection of Kant’s view of modality, and whether these considerations are helpful in developing a viable version of Kant’s view. First, if I make a statement of the form “x possibly exists”, then according to the view I have

21

In the course of reasoning we are guided by our grasp of the internal relations between the concepts involved.

attributed to Kant, this conveys the information that the proposition that x exists is compatible with the formal conditions on experience. It does not appear to be merely expressive of this, but in fact has that content, with clearly defined truth-conditions, i.e. the compatibility or not of that proposition with those.22 So an expressivist account does not immediately seem appropriate. However, any relative account of modality of this kind faces a challenge to give an account of logical necessity. If a Baldwin-style account of modality were to have any bite, it is likely that it would have to be here, at the level of logical necessity. After all, Kant owes us an account of the notions of compatibility and determination which underlie his account of the modality of things. If I am right to read these as logical compatibilty