Cognizing Coexistence: Perceptions and their Synthetic Unity in Kant’s 3rd Analogy

  • Andrew Werner orcid logo (University of Houston)


In the 3rd Analogy, Kant claims that I can perceive that things coexist by synthesizing my perceptions in an order-indifferent way. Reigning orthodoxy holds that I first successively perceive different things, and then (through some further act) determine that the things I perceive coexist. Focusing on prominent examples of this approach, I argue that these accounts fail to do justice to the order-indifferent synthesis that Kant describes: Strawson explains the synthesis in a way which renders Kant’s argument in the 3rd Analogy obviously unconvincing, Watkins makes the synthesis irrelevant to Kant’s argument, while Longuenesse and Allison make the unity of the synthesis obscure. The problems with these views, I contend, show that Kant thinks the rule for synthesizing my perceptions is already operative in the successive perceptions, such that the fundamental act of perception already involves ‘objective time-determinations.’ This connects with the recent dispute about whether Kant is a conceptualist: my argument provides additional evidence that Kant is a conceptualist, while also extending the conceptualist reading to the 3rd Analogy in a novel way. For those who think conceptualism is wrong, my argument serves as a critical notice that non-conceptualists have yet to offer a satisfying interpretation of the 3rd Analogy.

Keywords: 3rd Analogy, Synthesis, Perception, Conceptualism vs. Non-Conceptualism, categories, Analytic of Principles

How to Cite:

Werner, A., (2023) “Cognizing Coexistence: Perceptions and their Synthetic Unity in Kant’s 3rd Analogy”, Journal of Modern Philosophy 5: 6. doi:



Published on
22 Sep 2023
Peer Reviewed

Turning from the tree, I see a pond in the distance—and I know that the tree and the pond coexist. That I see the pond after I saw the tree does not make me think that the tree might have ceased to exist; I know that the tree is still there behind me as I look at the pond. How?

In the 3rd Analogy, Kant explains that I can know that what I successively perceive coexists by combining my perceptions according to the rule that the order in which I perceive them is insignificant to what I perceive. In fact, I first perceived the tree, but I could have perceived the pond first. Where I combine my perceptions in this order-indifferent way, Kant claims, I can know (or, in his terms, ‘cognize’) that the objects I perceive coexist. As Kant puts it, ‘how does one cognize that they exist at one and the same time? If the order in the synthesis of the apprehension of this manifold is indifferent …’.1

Call this step in Kant’s argument ‘Order-Indifference.’ As many scholars recognize, Order-Indifference is central to Kant’s explanation of how I can cognize that different objects coexist. Nevertheless, I will argue that existing interpretations of it fail to capture its role in Kant’s argument.2 By providing a close reading of Kant’s account of Order-Indifference, I show that the rule for combining my perceptions operates already in perceiving. Only thus can I cognize that the tree and the pond coexist despite perceiving them successively.

My reading is incompatible with the most influential readings of the 3rd Analogy. In this paper, I focus on the interpretations put forth by Strawson, Watkins, Allison and Longuenesse. I show that their views face significant problems: either they fail to do justice to the importance of Order-Indifference in Kant’s argument (Watkins), or their interpretation of it leaves Kant’s argument hopeless (Strawson, Allison, and Longuenesse).

The interpretations put forth by these authors have been influential. They also all share the view of the Analogies as a response to what Watkins has aptly called ‘the problem of time-determination’ (2005: 188).3 On this view, I first successively perceive in a way that does not involve an objective time-determination (i.e., does not involve temporal determinations of the objects I perceive). This raises a problem: how can I cognize the time-determinations of what I perceive? On this view, I do so by synthesizing my perceptions in accordance with a rule that does involve an objective time-determination. I show that this reading of the Analogies cannot make sense of the 3rd Analogy. I contend that the role that Order-Indifference plays in Kant’s argument requires that the objective time-determination of coexistence is present already in perception, such that we are cognizant of coexistence even in our initial successive perceptions.

Reading the Analogies as responding to the problem of time-determination fits in neatly with many of the family of views according to which Kant is a non-conceptualist: someone who thinks the syntheses of the understanding are performed on acts of sensibility that are independent of those syntheses. By contrast, the reading that I put forward falls in line with the family of views called ‘conceptualist’, according to which the understanding is already operative in acts of perceiving. The primary philosophical (rather than textual) motivation for conceptualist interpretations of Kant’s Critique is to do justice to the fact that human mindedness is genuinely of the world rather than empty, such that perception enables contentful knowledge of the world; and that it is rational rather blind, such that perception opens our eyes to the world through the activity of the understanding. The guiding thought is that to do justice to these twin demands requires the understanding to inform or be at work in perception itself rather than merely act on perceptions. And so it is on my reading of the 3rd Analogy: the understanding is at work already in successive perceptions, and does not merely act on them.4

As my paper proposes a new interpretation of the starting point of the argument of the 3rd Analogy and presents a challenge to the most prominent existing interpretations of that argument, it should be of interest to all who are antecedently interested in the 3rd Analogy. And though my focus here is on the relatively understudied 3rd Analogy, if the argument I put forth convinces it will provide some impetus for rereading the first two Analogies along the lines that I outline. Thus, my argument should interest anyone who works on the first two Analogies as well.

Further, my paper also extends the ‘conceptualist reading’ to apply to the 3rd Analogy in a novel way. While one prominent conceptualist interpreter has offered a reading of the 3rd Analogy (Longuenesse), I argue that her interpretation of it does not do it justice because it does not enable perception to open our eyes to the world, and so fails by the lights of the philosophical motivation that animates it; I am aware of no other conceptualist who has put forward an interpretation of the 3rd Analogy, so my paper will be of interest to those who want to see that interpretation worked out in more detail beyond the much-discussed texts of the Transcendental Aesthetic and Deduction. Moreover, my paper presents a novel argument for conceptualism, one rooted in the detail of the 3rd Analogy.

Finally, my paper also serves as a critical notice to those who sympathize with non-conceptualist interpretations of Kant to say more about the 3rd Analogy. Existing non-conceptualist interpretations, I argue, have a hard time making sense of Kant’s appeal to Order-Indifference. I acknowledge that it is unlikely that committed non-conceptualist interpreters of Kant will be convinced to give up their view because of the 3rd Analogy. However, for those scholars my article shows that they need to do more to explain the argument of the 3rd Analogy.

In §1 I clarify Kant’s use of the term ‘perception’ (‘Wahrnehmung’) and situate my account in relation to Clinton Tolley’s recent discussion of this topic. In §2 I show how the interpretations of the 3rd Analogy put forth by Strawson, Watkins, Longuenesse and Allison fail to make sense of Order-Indifference. In §3, I develop my own interpretation of Order-Indifference and the role it plays in Kant’s argument. I conclude in §4.

§1 The Order-Indifference of Our Perceptions

In the 3rd Analogy, Kant claims that I cognize that things ‘exist at one and the same time’ by combining my successive perceptions of them in an order-indifferent way (A211/B258). Or:

Order-Indifference: To cognize that states of substances that I successively perceive coexist, I must synthesize my perceptions according to the rule that I can perceive the states in any order. (Relatedly, I will say a sequence of perceptions is ‘order-indifferent’ if they have been synthesized in this fashion.)5

Kant’s claim is widely acknowledged in the literature on the 3rd Analogy, as is the parallel claim from the 2nd Analogy. So, I take the claim to be relatively uncontroversial. In what follows, I will show that existing interpretations of the role that this claim plays in Kant’s argument fail to do it justice, before turning to give an alternative interpretation. In this section, I want to explain what Kant means by ‘perception’ (‘Wahrnehmung’).

Kant seems to use the term ‘perception’ in different senses at different points in the Analogies. Sometimes, as Kant uses the term, it picks out something that does not yet involve cognition of any temporal determinations of what one perceives—for instance, when Kant writes that ‘through the mere perception the objective relation of the appearances that are succeeding one another remains undetermined’ (B234). But sometimes it does involve cognition of temporal determinations—for instance, when Kant writes that ‘[a]lteration can be perceived only in substances, and arising or perishing per se cannot be a possible perception unless it concerns merely a determination of that which persists’ (A188/B231; B225, B233, and A198/B243). On this usage, I can perceive alterations of a substance, and alteration is an objective relation of the appearances that are succeeding. This apparently conflicts with the prior claim. What, then, does Kant mean by ‘perception’?

Recent work by Clinton Tolley helps answer this question. According to Tolley, Kant’s argument in the Principles is developmental in that it progresses from intuitions (Axioms) to perceptions (Anticipations) to experience (Analogies) (Tolley 2019). He has argued that, for Kant, perception in the first instance is consciousness of either a sensation or an intuition (A119–20). So, perceptions add consciousness to intuition—in particular, Tolley argues, consciousness of the manifold contained in the intuition (B202–3; Tolley 2016: 86; 2018: §3). Tolley also thinks that perception is not yet cognition of an object (not yet experience, in Kant’s technical sense of that term), but merely consciousness of a representation—to arrive at cognition of an object requires further cognitive processing.6

Recognizing, with Tolley, that the Principles develop from perception to experience helps us understand Kant’s shifting use of the term ‘perception.’ In the Analogies, Kant’s explicit topic is experience (they are the ‘Analogies of Experience’) rather than perception. Experience, Kant says, is the determination of an object through a synthesis of perceptions (B219). So, Kant’s topic in the Analogies is a synthesis of perceptions: specifically, the synthesis that determines the temporality of the objects perceived. So synthesized, what we perceive is an object, and our perception is cognition of it. Kant evidently thinks it appropriate to refer both to what is synthesized and to the synthesis as perceptions. We can, following Kant, call the first sense of perception, which involves no objective time determination, ‘mere perception’; we can, adding to Kant’s terminology, call the synthesis of perceptions, which involves objective time determination, ‘enriched perceptions.’ Enriched perceptions make up experience.

Using this terminological distinction, we can make sense of Kant’s apparently conflicting claims about perception. ‘Mere perception’ does not determine the objective relation of successively perceived appearances; in the sense of ‘mere perception,’ I do not perceive alterations. But, in the sense of enriched perception, I do perceive alteration. Conforming to the enriched side of Kant’s usage, unless otherwise noted in what follows when I talk of ‘perception’ I will mean perception as synthesized (enriched perception).

This essay at disambiguation naturally raises the question: How does the synthesis of perceptions relate to perception, enriched perception to mere perception? Is the synthesis of perceptions necessary for (mere) perception or logically posterior to it?

Tolley takes Kant to hold that the capacity to merely perceive and its acts are independent of the capacity for enriched perception; he also holds that the capacity for mere perception and its acts are independent of the activity of the understanding (Tolley 2013). So, on his view, a being could merely perceive appearances without being able to perceive appearances in an enriched way, and I can merely perceive appearances in a way that involves no objective time determinations. To arrive at objective time-determinations, I must in some way augment my acts of mere perception, perhaps by interpreting the acts of mere perception through an activity of the understanding; the augmentation in question brings into play another capacity (or perhaps many different capacities), the possession of which is not implied by the possession of the capacity for mere perception.

Tolley might be right—but the fact that the Principles develop does not show he is. For we must ask how Kant thinks about the development. One might take Tolley’s view, or one might instead argue that Kant builds up an essentially inseparable sequence of capacities, showing developmentally that each capacity depends on the one that follows it.7 On this view, to which we shall return in §3, mere perception is dependent for its possibility upon enriched perception.

The readings of the 3rd Analogy that I consider in §2 all agree with Tolley in taking it that mere perception is not dependent for its possibility on enriched perception. I will argue that these interpretations make the argument of the 3rd Analogy mysterious and then suggest (§3) that we can make the argument of the 3rd Analogy unmysterious if we adopt the view that mere perceptions depend upon the synthetic unity that connects those perceptions with one another (enriched perceptions).

§2 A Puzzle about Order-Indifference

In this section, I will consider three interpretations of the role played by Order-Indifference and show that all of them face significant problems. In §3, I will suggest a way to avoid these problems.

§2.1 The Criterial Theory

Let’s start with the interpretation put forth by Strawson, according to which Order-Indifference describes a feature of the succession of my perceptions that I can use as a ‘criterion’ for determining whether the states I perceive coexist. He writes,

our knowledge, through perception, of the coexistence of things depends upon our implicit recognition of the order-indifference of the relevant perceptions. Lack or possession of order-indifference on the part of our perceptions is, [Kant] seems to say, our criterion—whether we reflectively realize the fact or not—of objective succession or coexistence. (Strawson 1966: 134)

So, says Strawson, my (perhaps implicit) recognition of the order-indifference of my perceptions is the basis upon which I determine that what I perceive coexists. That is, I can know whether my perceptions are order-indifferent in a way that is epistemically prior to my knowing that the objects I perceive in that fashion exist at the same time. The order-indifference of my perceptions provides, Strawson thinks, my only available evidence (or criterion) for determining that the objects I perceive exist at the same time.

How does Strawson’s Kant get from the connection between Order-Indifference and the coexistence of objects to a causal relation between objects? By the infamous ‘non-sequitur of numbing grossness’ (Strawson 1966: 137). Kant confuses the fact that I could have perceived the objects in any order with the fact that the objects causally interact with one another: ‘the order-indifference of perceptions is equated with the mutual causal influence of coexisting objects’ (Strawson 1966: 139). So, by confusing the necessary connection of our perceptions with the necessary connections of what we perceive, Kant thinks he has shown that all coexistent objects must stand in mutual causal interaction.

Let’s call Strawson’s view a ‘criterial theory’ of Order-Indifference. A criterial theory invokes our knowledge of the order-indifference of a sequence of perceptions as evidence for the coexistence of what we perceive. Strawson’s version of the criterial theory is, by his own lights, philosophically hopeless. One might wonder, however, whether some other version of the criterial theory might work: specifically, perhaps knowledge that a particular sequence of perceptions is order-indifferent can serve as evidence for the coexistence of those objects and then we can conclude, on the basis of some further premises, that that knowledge is possible only if the objects perceived in that way mutually interact with one another. Perhaps Kant did not confuse the two relations of Order-Indifference and causal interaction, but has resources for supplying a bridge from the one to the other?

Unfortunately, as many have noted, the trouble with the criterial interpretation does not at root lie in the non-sequitur of numbing grossness, but rather in the claim that knowledge of the order-indifference of a sequence of perceptions is a criterion for the coexistence of those objects. For it does not seem like we can know that a given sequence of perceptions is order-indifferent without thereby or already knowing that the objects perceived in that sequence coexist.

I think the best possible response to this objection open to a defender of the criterial theory is the following: I can know that my perceptions are order-indifferent by perceiving the same objects in reverse order, and this knowledge can be my evidence that the objects I perceive coexist. I first perceive the earth and then the moon; then, to determine that my perceptions are order-indifferent, I turn back from the moon to the earth (etc.). When my perceptions are ‘reversible’ in this way, I use that fact as evidence for thinking that the things I perceive coexist.8

However, reversibility is not a criterion for the fact that the objects I perceive coexist. For, as Paul Guyer has shown, the possibility of subsequently perceiving in a different sequence is neither necessary nor sufficient for claiming that the objects perceived in that way coexist (Guyer 1987: 270–71). Not necessary: perhaps, after looking at the moon, I turn to the earth and, while looking at the earth, the moon is destroyed, so that the moon is not there when I look back. Still the earth and the moon coexisted; still, I can cognize that they coexisted. Not sufficient: perhaps, when looking at the earth, the moon has not yet come into existence, but the moon comes to exist by the time I look up. Indeed, one can simply imagine that they oscillate such that the emergence of the one causes the other to be destroyed, which causes the one to be destroyed, which causes the other to emerge, etc. Thus, I can turn from the one to the other in whatever order and however many times I like, and yet they will never have coexisted. This case is absurd, but nothing in subsequently changing the course of my perceptions is incompatible with this absurdity.

That I can subsequently reverse course in my successive perceptions of distinct things is neither necessary nor sufficient evidence for thinking that those states coexist. By contrast, that I can perceive the objects in any order suffices to show that the states coexisted and is necessary for the states to coexist (on the assumptions that the states are perceivable, and that their place in time can be determined). So, reversibility is neither sufficient nor necessary for cognizing coexistence, while Order-Indifference is.

The criterial theory will have to come up with another basis (apart from cognizing the coexistence of what I perceive) for concluding that I could have perceived the objects in a different order, since reversibility won’t do. It is not clear what other basis there could be. If there is none, then either Kant’s argument in the 3rd Analogy does not work, or (as I and most other recent interpreters think) the criterial theory must be wrong.

§2.2 Is Order-Indifference Really that Significant for Kant’s Argument?

Since Order-Indifference cannot serve as my evidence for cognizing coexistence, and Kant’s task in the 3rd Analogy is to try to explain how I can cognize coexistence (ultimately by appealing to reciprocal interaction), many scholars conclude that Order-Indifference is inessential to Kant’s argument. In this section, I will focus on the influential and detailed version of this strategy articulated by Eric Watkins.9

According to Watkins, Order-Indifference plays no direct role in the argument of the 3rd Analogy, but rather helps Kant distinguish his position from his predecessors. Namely, according to Watkins, philosophers before Kant thought that we could cognize the time determinations of the objects we perceive by deriving these determinations from (features of) the subjective sequence of our perceptions. Order-Indifference forms part of Kant’s strategy for helping his readers see that he rejects that view (Watkins 2005: 205–6; cp. 1997: 419).

There are two problems with Watkins’s strategy. First, the discussion of Order-Indifference does not play the role that Watkins says it does. Two other claims that Kant makes do help clarify Kant’s position in the manner Watkins suggests: first, Kant’s claim that I perceive successively regardless of the time determinations of the objects I perceive (a frequent refrain in the first two Analogies), and, second, his claim that I cannot tell the time at which I perceive objects from the content of my perceptions (e.g., B257). From these two claims, it follows that the subjective order of my perceptions does not license an inference to any objective time determination. That argument requires no appeal to Order-Indifference.10 And if one wanted more clarity, surely Kant’s claim, also cited by Watkins, that one must ‘derive the subjective sequence of apprehension from the objective sequence of appearances’ (A193/B238) would suffice. Indeed, Order-Indifference might mislead Kant’s readers insofar as it suggests a close connection between the subjective order and the objective order: Order-Indifference, remember, describes the subjective succession, and (if somehow known) would license the conclusion that the objects I perceived coexisted. Readers (like Strawson) might be misled by this, seeing it as an expression of a commitment to the traditional idea that one infers the objective order from the subjective order.

Second, and more importantly, the idea that Kant invokes Order-Indifference merely to fend off a misunderstanding does not fit the text. Here is the relevant portion of the text, when Kant introduces Order-Indifference:

Things are simultaneous insofar as they exist at one and the same time. But how does one cognize that they exist at one and the same time? If the order in the synthesis of the apprehension of this manifold is indifferent, i.e., if it can proceed from A through B, C, D to E, but also conversely from E to A. (A211/B258)

In this passage, Kant describes the way I cognize that distinct objects coexist. Since, for example, the earth and the moon coexist, I can perceive them in any order. I perceive successively, so, in fact, I perceive them in one order—say, first the earth and then the moon. I cognize that I could have perceived first the moon and then the earth by synthesizing my successive perceptions according to the rule that the order in which I perceive these objects has no objective significance. And this, according to Kant, is how I cognize coexistence.

Kant says that Order-Indifference is an answer to the question ‘how does one cognize that they exist at one and the same time?’ (A211/B258). He also says that ‘on this account, since the perception of these objects can follow each other reciprocally, I say that they exist simultaneously’ (B257). Watkins sees that, for Kant, the order-indifference of our perceptions does not serve as a criterion for determining that what I perceive coexists: Kant does not say that I determine that my perceptions are order-indifferent and, on that basis, determine that the substances I perceive coexist. But Watkins recoils too much from the criterial theory and fails to do justice to Kant’s claim that I ‘cognize’ (‘say’) that the substances I perceive coexist by perceiving them in an order-indifferent way.11 One can see why: it is not at all clear what role Order-Indifference could play in Kant’s argument once one sees that it is not our evidence for cognizing coexistence. Hence, the puzzle: how to account for Order-Indifference?

§2.3 The Interpreting Theory

According to Kant, Order-Indifference articulates how we cognize that the objects we perceive coexist. But Order-Indifference cannot serve as our evidence for cognizing that the objects coexist. Perhaps, then, Order-Indifference is a description of the synthesis we effect on our successive perceptions, by means of which we cognize that the objects we perceive coexist. On this view, the synthesis is an interpretation of what we merely perceive. So, let’s call the view the ‘interpreting theory’ of Order-Indifference. Beatrice Longuenesse and Henry Allison defend versions of this theory. I will first explain the interpretation and then raise an objection to it.

Like Watkins and against the criterial theory, Longuenesse and Allison hold that Kant thinks that I cannot infer the temporal order of the states that I perceive from the temporal order of my successive perceptions.12 Unlike Watkins, they see Order-Indifference as Kant’s explanation of how we ‘determine that things we apprehend only successively are objectively simultaneous’ (Longuenesse 1998: 387). The successive perceptions provide me with data that I interpret as order-indifferent, therein determining that the states that I perceive coexist.13 Kant’s argument in the 3rd Analogy is that I can effect that interpretation on a sequence of perceptions only by subjecting them to the rule that the objects I perceive in this manner causally interact with one another.

How does the interpretation of mere perceptions work? The idea is clearest for the 2nd Analogy.14 In that case, I successively perceive the same substance in contrary states. Let’s assume that the 1st Analogy has given us the resources we need to determine that we are perceiving two states of one substance. We can tell, from the content of our perceptions, that the states in question are contrary to one another, and so they cannot coexist in the same substance. As their temporal order must be determinate, I interpret my successive perceptions by synthesizing them according to the rule that their order is objectively significant. For example, I determine that the stone goes from a state of being cold to a state of being warm; that is objectively different from the interpretation according to which the stone goes from a state of being warm to a state of being cold. The argument of the 2nd Analogy is then meant to show that I effect this interpretation of what I merely perceive through applying the rule that the change in what I perceive happens in accordance with the law of cause and effect. And I can do this only by determining the transition to be the result of some cause. I interpret the stone as changing from being cold to being warm by cognizing that some cause brought that change (rather than the opposite change) about.

So much by way of explaining the interpreting theory. It has a great deal of plausibility: it seems to do justice to what Kant says about the synthesis of our perceptions in the 2nd Analogy and to avoid the philosophical and exegetical troubles with the criterial theory. The theory founders, however, on the 3rd Analogy’s appeal to Order-Indifference.

To make the view work for the 3rd Analogy, we must find some data that we can tell involves or suggests the coexistence of states of distinct substances (to focus on the primary case of interest in the 3rd Analogy), then arriving, eventually, at the category of community as that in virtue of which we can tell that the states coexist. But what is the data? If I perceive first the moon and then the earth, it might be plausible to suppose that I can determine that I am perceiving two distinct substances. I thus might rule out that I am perceiving a change, or contrary states of the same substance. But none of this tells me anything at all about the coexistence or succession of the perceived states of those substances: it does not make determining them to coexist any more or less reasonable than determining that they do not coexist.

The cases of the 3rd Analogy and the 2nd Analogy seem like they might be different with respect to the plausibility of the interpreting theory, at least on a certain assumption. The assumption is that the 1st Analogy provides us with whatever is needed to determine that we are successively perceiving the same substance. The extra unity provided by the determination of the sameness of the substance in the 2nd Analogy makes the interpreting theory seem plausible, as it provides the basis for placing contrary states into distinct times: the two states cannot coexist, as they are contraries, and it is surely plausible that the contrariety of the states is available to perception (a result from the Axioms and the Anticipations). There is no such substantial unity to work with in the 3rd Analogy: the state of one substance might well have changed just before we turn to perceive it, or it might not have changed, and nothing in the perceived content of the states suggests the one interpretation or the other. On the interpreting theory, I contend, it is obscure what would support interpreting the states we perceive in one way rather than the other.15

(Of course, it would be natural at this point to ask how the interpreting theory accounts for the determination that the substance is the same across the successive perceptions, since it does not seem like mere perception would provide us with the evidence requisite for that knowledge. But pursuing this question would require examining not only the 2nd Analogy, but also the 1st, and I will set it aside here.)

In response to my objection to the interpreting theory, one might argue that my interpretation of successive perceptions can draw on my background empirical theory of the world. For instance, I have learned some astronomical theory, ultimately on the basis of hundreds of thousands of observations (relayed via testimony). According to that theory, astronomical bodies tend to endure and move in certain regular patterns. And, using that background knowledge, I can interpret my successive perceptions of the moon and sun as successive perceptions of coexisting states of distinct substances. Such an interpretation may not be entailed by my perceptions plus my background theory, but it is much more reasonable than the alternative interpretation(s) given that background theory.

I grant that if we assume access to the background empirical theory, together with its basis in prior observations, then we would have reason to favor one interpretation of the data provided by mere perception over another. However, that background empirical theory is ultimately acquired through perception of objective temporal determinations of distinct states of substances. On the interpreting theory, these objective temporal determinations must themselves be the result of an interpretation of mere perceptions. So, to have access to the background empirical theory requires having already answered the objection without appealing to it—it requires finding within mere perception alone some basis for favoring one interpretation over another. My objection does not turn on demanding some particularly high threshold of justification, and it would be answered if there was any reason at all to favor one interpretation over another. But, since the contents of mere perceptions of distinct substances involve no objective temporal determinations of the states so perceived, it is unclear how they could provide such a basis.16

So, the interpreting theory, as applied to the synthesis described in the 3rd Analogy, is obscure, and I think it reasonable to suspect that it cannot become clearer simply by spelling the view out further. How, then, shall we solve the puzzle about Order-Indifference?

§3 Perceiving Coexistence

So far, we have considered three views of the role of Order-Indifference in the 3rd Analogy. One view fails to acknowledge Kant’s claim that Order-Indifference is the way in which we cognize that things coexist with one another. The other two views attempt to explain the claim but fail in the attempt. The criterial theory claims that Kant invokes Order-Indifference as our criterion for determining whether things coexist, and the interpreting theory claims that Order-Indifference is the act by which we interpret the sequence of perceptions and thereby determine that the objects perceived coexist. Both views fail for what is at root the same reason: the data available prior to cognizing coexistence is insufficient to justify the claim or interpretation that what we perceive coexists.

For the criterial theory, Order-Indifference is meant to serve as evidence by means of which we cognize that things coexist. But we cannot use Order-Indifference as evidence for the claim that things coexist because we can only cognize that our perceptions are order-indifferent if we already know that the things we perceive coexist. For the interpreting theory, Order-Indifference is meant to be our interpretation of the data available to us from mere perception. But we cannot justify combining our perceptions in an order-indifferent way, and therein interpret what we perceive to coexist, on the basis of what is made available by mere perception. How might we avoid the problem that plagues both the criterial and interpreting theories?

The solution, I suggest, is simple, though it has far-reaching consequences. In the B-edition version of the principle of the 3rd Analogy, Kant says that substances ‘can be perceived in space as simultaneous’ (B256). According to the interpretations we have considered so far, Kant means that substances can be perceived as simultaneous only after the understanding acts on the mere perceptions of what is in space. These views fail: mere perceptions do not provide enough for the understanding to produce the enriched perception of coexistence rather than the enriched perception of objective succession. On that diagnosis, the solution must be that Kant thinks that, in the fundamental case, an act of perception is an act of enriched rather than mere perception.

Let me clarify what I mean. In §1, I followed Tolley’s suggestion that what explains Kant’s ambiguous use of the term ‘perception’ is that the course of the Principles is developmental. But I also noted that to say that the Principles are developmental is not yet to say how the stages of that development relate to one another. On one view, the view one finds in Tolley, experience arises from acts of a capacity of (mere) perception that are augmented by the acts of other capacities, eventually bringing in the understanding. Key to this picture is that the capacity to (merely) perceive is not dependent for its activity on the subsequent capacities—one could have the capacity to (merely) perceive regardless of whether one had the further capacities. But one might instead think that the development is a development of different, increasingly richer aspects of what is involved in the fundamental case of an act of perception, such that the capacity to perceive is dependent upon the other capacities and its defining act is an act that involves the activity of those other capacities (including, most significantly for our purposes, the understanding).

Both the criterial and interpreting theories hold that, for Kant, the capacity to merely perceive is separable from the capacity to perceive in an enriched sense, such that we arrive at acts of the second capacity only through acts of the understanding on the results of the acts of the first capacity: I must determine that the things I perceive coexist on the basis of first perceiving them in a way that involves no objective time determination. In the face of the problem with this view, the natural suggestion is that there is no initial stage prior to the temporal determination of coexistence. The capacity to merely perceive is not a self-standing capacity: it is a partial description of the capacity to perceive in an enriched sense.

Does my view entail that, for Kant, there are no acts of mere perception? No, it does not, and that is why I refer above to ‘the fundamental case’ of an act of the capacity to perceive. For perhaps I can merely perceive—that is, perhaps it is possible that I engage in acts of mere perception, or acts which involve no objective time determination of the successive manifolds that I perceive. I may, for instance, associate my perception of the moon with my perception of the sun in a way which involves no determination of their coexistence (or succession). The point I am making does not exclude the possibility of that. My point, rather, is that such acts are derivative or parasitic upon the more fundamental or capacity-defining act of enriched perception. I can, perhaps, merely perceive the sun and the moon—but only if I can determine that they coexist. Such, anyway, is the view that I am attributing to Kant.17

On the view I am suggesting, when I perceive the earth (before perceiving the moon), I am cognizant that the earth exists at a time at which other things, like the moon, might exist. In first perceiving the earth, I do not thereby know what other things coexist with it—but I can know, on the basis of what I go on to perceive, what coexists with it. According to Kant, that is possible only if, in perceiving the earth, I am cognizant that I might have perceived whatever else exists at the time at which I perceived the earth (had I been positioned differently—for instance, had my head been turned). In other words, in perceiving the earth, I am in a position to judge that it coexists with an indefinite number of other things, and the capacity I exercise in perceiving the earth is a capacity to cognize what other things coexist with the earth.18 (Kant’s argument in the rest of the 3rd Analogy is meant to show that the capacity to perceive is a capacity to cognize coexistence only if the things that coexist causally interact with one another.)

I have said that my capacity to perceive is the capacity to perceive coexistence: I can perceive the earth only because I can perceive other substances as coexisting with it. But, one may wonder, how can I determine in a given case whether the states I have successively perceived coexist with or succeed one another? For surely one of the main items on Kant’s agenda in the 2nd and 3rd Analogies is to explain the difference between successive perceptions of a house and successive perceptions of a moving ship. How does my appeal to the capacity to perceive coexistence help explain the difference between those two cases?

There is clearly a sense in which Kant is trying to explain how I can know of one set of successive perceptions that they are perceptions of a change and of another that they are perceptions of coexisting states of substances. There are different interpretations of what this might mean, however. First, one might think that Kant means to explain how, given some set of successive perceptions, I can subsequently determine whether they are perceptions of change or of coexistence. Second, one might think that Kant starts from the claim that I can perceive that things are changing and that things coexist, and is asking how I can do that. I am arguing for the second interpretation. But, if the second interpretation is right, then the objection falls to the ground: Kant takes for granted that I can perceive that things coexist with one another, and specifies conditions for the possibility of that. There is a perceptually available difference between successive perceptions of a house and successive perceptions of a moving ship. Kant is giving an account of the conditions of possibility of that difference.

The criterial and interpreting theories both hold that Kant is trying to explain the basis on which I determine that the states coexist in the one case and the basis on which I determine that they succeed one another in the other case. That’s not quite right, on my view, for that assumes that the only answer Kant can offer appeals to features of what is available to us in mere perception. (From this vantage point, it does not matter whether those features offer an epistemological, psychological, metaphysical or putatively transcendental answer to the ‘On the basis of what?’ question.) I do not believe that Kant asks this ‘On the basis of what?’ question. And, I think, if one were to press him to explain on what basis I perceive the states of the house to coexist while I perceive the states of the moving ship to succeed one another, his answer would be: because the states of the house do coexist, while the states of the moving ship do not. At this point, one would be well within one’s rights to ask Kant to defend that answer (against, e.g., an appeal to subjective habits of association), and that is where (on the criterial and interpreting theories) the appeal to features of mere perception would come in. But my suggestion is that Kant is not trying to answer this question—he instead articulates the conditions of possibility of the representations of temporal determination (of coexistence and succession) which the ‘On the basis of what?’ question takes for granted. And his argument in the 3rd Analogy is that the perceptual representation of the coexistence of states of substances depends upon the objective determination that those substances causally interact with one another.19 (Again, I have not sought to defend his argument in the 3rd Analogy; I have instead tried to explain the starting point for his argument.)

Before connecting my interpretation to larger debates about Kant’s project in the Critique, I want to clarify it in two further respects. First, note that I mean ‘perceive coexistence’ to imply knowingly perceiving coexistence. All agree that Kant is talking about how I cognize that things coexist on the basis of perception. To invoke a kind of perception that involves perceiving coexistence unknowingly would just reraise the problem that besets the criterial and interpreting theories: on the basis of what do I come to know that the things I perceive coexist?

Further, to say that I knowingly perceive coexistence means that perceiving puts me in the position to judge that states of distinct substances coexist. This does not mean that perceptions are judgments, or even that perceiving involves judging: the way the categories inform perception does not turn perception into a judgment. I am not, in knowingly perceiving the moon and the earth as coexisting, exercising the capacity to judge, since I am not judging that they coexist—rather, I am exercising the capacity to perceive, a capacity that puts me in the position to make judgments about the moon and the sun that involve the (implicit or explicit) recognition that they coexist.20

My solution to the puzzle about Order-Indifference involves attributing a version of what is typically called ‘conceptualism’ to Kant. ‘Conceptualism’ as applied to Kant is, roughly, the view that the understanding operates in and not just on sensibility. As I noted in my introduction, the primary philosophical motivation for this view is that it is required to enable judgment to have both content (or be about the world) and to be sensitive to reason. The idea is that if sensibility is independent of the understanding, then acts of sensibility will be blind and acts of the understanding will be empty. I will follow Jim Conant in calling the view the ‘transformative conception of human mindedness,’ with the idea being that the operation of the understanding in sensibility transforms the very nature of sensibility, so that it is a distinctively rational form of sensibility.21 The term ‘transformative’ better highlights the philosophical aspirations of the view, as I understand it: the idea is not to reduce sensibility to the understanding (intuitions to concepts) but to articulate some kind of inseparable unity of the two.

I will not rehearse the voluminous debate about whether Kant’s view is transformative or non-conceptualist, as my topic is the 3rd Analogy. But my point is relevant to the debate because my solution to the puzzle about Order-Indifference attributes a transformative view to Kant. Our capacity to merely perceive, once fully in view, is the capacity to perceive coexistence because it presupposes the rule, supplied by the understanding, to combine successive perceptions of coexisting things in an order-indifferent way. (Note that my topic is Kant’s account of perception (in the 3rd Analogy) and not intuition. Typically, defenders of the transformative view of Kant target intuition. While what I say is in the spirit of that view, it is logically independent of it: what I say is consistent with the view that intuition is independent of the activity of the understanding. This should make my view more tolerable to defenders of non-conceptualism who draw a sharp distinction between intuition and perception.)

It may surprise that I group Longuenesse with the non-conceptualists. Certainly, she embraces a central aspect of the transformative view when she defends the claim that perceptions are as such informed by the relational categories of the Analogies. Thus, she would deny the non-conceptualist claim that I can perceive in a way that is independent of the understanding. But she denies that mere perception puts me in a position to judge that the objects I perceive fall under any of the relational categories. For that judgment, I must first interpret what I perceive.22 As I argued in §2.3, it is unclear how we can become cognizant of the coexistence of what we perceive if we proceed in this way. And that is to say that, with respect to the objective time determination of coexistence, perception is blind and the understanding is empty—precisely because with respect to that determination the understanding acts on and not in mere perception. Thus, while Longuenesse’s view is transformative overall, her reading of the 3rd Analogy betrays the philosophical aspiration of the transformative interpretation.23

I am proposing that we can solve the puzzle about Order-Indifference if we credit Kant with the view that we perceive coexistence, such that the fundamental act of perception is an act of enriched perception. I have said that this is a natural suggestion, given the problem that besets the criterial and interpreting theories. I have not offered a decisive argument showing that it is the only way to explain Order-Indifference. Perhaps one can explain Order-Indifference in a different way. Certainly, people attracted to non-conceptualism, or criticisms of the transformative view, are not likely to be persuaded to abandon their view by any arguments about the 3rd Analogy. I contend, however, that my argument shows that prominent versions of non-conceptualist readings of the 3rd Analogy fail. I thus invite non-conceptualists to find other solutions to the puzzle about Order-Indifference.

§4 Conclusion

Kant opens the 3rd Analogy by claiming that we can cognize coexistence by synthesizing our successive perceptions according to the rule that the order of the succession is objectively insignificant. One immediately wants to know: how do the successive perceptions relate to the synthesis of those perceptions? A common way of reading the Analogies takes it that the successive perceptions are independent of and prior to their synthesis, such that the problem posed in the Analogies is a ‘problem of time-determination’ (Watkins 2005: 188): how can I cognize the temporal relation between things on the basis of perceptions that are always successive?

I have argued that the influential versions of this strategy put forth by Strawson, Watkins, Longuenesse and Allison all face problems. The interpretation put forth by Watkins fails to do justice to Kant’s claim that the synthesis of our perceptions is the way in which we cognize that things coexist. And the interpretations put forth by Strawson, Longuenesse, and Allison fail because the successive perceptions do not provide enough material to license either a conclusion or an interpretation of coexistence.

This suggests that, for the 3rd Analogy, we need to understand the relation between the successive perceptions and the synthesis of perceptions differently. Rather than construing the first as independent of the second, we should instead see the second as already operative in the first. Our perception of an object already involves the rule for combining that perception with perceptions of other objects, the rule that enables us to cognize the coexistence of those objects. Thus, upon successively perceiving coexisting things, we are in a position to judge that those things coexist without needing to further work up the successive perceptions. Perhaps one can understand how the successive perceptions relate to their synthesis differently. In that case, more work is necessary to explain that different relation. However, if my reading convinces, then the 3rd Analogy gives further support to transformative (or conceptualist) readings of the Critique.24


  1. Kant (1998: A211/B258). I follow the standard convention of citing Kant’s Critique of Pure Reason using the A/B paginations; I cite other works by Kant following the Akadamie Ausgabe edition. I follow the translations found in the Cambridge edition of his works, as found in the bibliography. [^]
  2. There is more to the 3rd Analogy than Order-Indifference. Recent scholarship has illuminated the metaphysical nature of reciprocal causality, in particular how it relates to Leibnizian monadology and Newtonian physics (Watkins 1997; 2005; Friedman 2013), the role played by space in the 3rd Analogy (Edwards 2000; Messina 2017; 2018), and connections between the 3rd Analogy and other aspects of Kant’s critical system (Payne and Thorpe 2011; Tizzard 2020). Though I cannot discuss these other topics here, I believe our appreciation of each would profit from a better understanding of the role of Order-Indifference in the argument of the 3rd Analogy. I hope to pursue these connections in other work. [^]
  3. On this point he is following Paul Guyer’s treatment of the Analogies as part of Kant’s overall theory of time-determination (1987: 172–75, 241–49). [^]
  4. Note that my topic in this paper is perception rather than intuition; much of the literature on the conceptualism/non-conceptualism debate has focused on intuition (sometimes losing sight of the difference between intuition and perception). My position in this paper is neutral on this more central topic of that debate, consistent with both conceptualism and non-conceptualism about intuition. For more on this, see §3. [^]
  5. In the 3rd Analogy, Kant uses variables (A, B, C, etc.; less formally, thing and object) to refer to the items that coexist with one another. Over what domain do these variables range? One might take the range to be substances, states of substances, or events. One might even think the variables range over all three. I follow Eric Watkins in thinking that the variables range over states of substances: if they just referred to substances, then one could infer from the 1st Analogy’s claim that all substances are permanent the conclusion that all substances coexist, and yet Kant does not make that argument (nor could that argument replace the 3rd Analogy) (2005: 221–22). And it is unlikely that the variables range over events, since Kant nowhere discusses the simultaneity of events as an example in the 3rd Analogy and it is prima facie unclear how two distinct events could stand in a relation of reciprocal causality (and even more unclear how they could stand in a relation of reciprocal causality in the same sense as can enduring states of distinct substances). In light of these arguments from Watkins, in what follows I will refer to what coexists as states of substances, or states for short (and I will also continue to use the less formal variables of ‘thing’ and ‘object’ to range over states of substances). However, nothing in my argument depends upon taking this view of what A and B range over—my argument should still apply even if the variables range over substances and events. Note that, as I have defined it, Order-Indifference will apply when I perceive states of distinct substances, and also distinct states of the same substance. The argument of the 3rd Analogy is primarily about the interaction of substances, and so Kant’s focus is on the former case, but his discussion of the perception of simultaneously existing distinct parts of a house (see A190/B235ff) suggests that his argument will also apply to the successive perceptions of states of the same substance. My thanks to a reviewer for noting this. [^]
  6. For further helpful reflections on the distinctions between intuition, perception, and imagination, see also Matherne (2015: 751–56). [^]
  7. Conant takes this view (2016). [^]
  8. C. D. Broad defends this position (Broad 1926: 199). L. W. Beck defends a position quite close to this, only he seems to confuse Order-Indifference with reversibility (1978: 137–38, 148–51). [^]
  9. Others who take this route include Melnick (1973: 82–83, 94–95), Guyer (1987: 247–48), and Paton (1936: 2:299–302). [^]
  10. Watkins claims that Order-Indifference is key to justifying that one cannot infer the objective order from the subjective order. But a close look at his reasoning (2005: 220) reveals that Order-Indifference is an idle wheel in this regard. (Consider also that he points the reader to a supposedly parallel reconstruction of the 2nd Analogy; but irreversibility—his term for the order-invariance of our perceptions—plays no role in his reconstruction of that argument (2005: 208). If the intended parallel is taken seriously, Order-Indifference must play no role in his reconstruction of the 3rd Analogy.) [^]
  11. See also Kant’s discussion of combining our perceptions in the elucidation at A214/B261. [^]
  12. In what follows, unless otherwise noted, I am interpreting what Longuenesse (1998: 387–90; 2005c: 199–204) argues and what Allison (2004: 263–66) argues. Also relevant are their objections to Strawson (Longuenesse 1998: 366–68; Allison 2004: 255–56). [^]
  13. Longuenesse and Allison do not agree on all aspects of how to understand the act of interpreting the states I perceive in accordance with the category of community. The two most significant disagreements concern the role of the categories in the synthesis and the relation between our capacity to perceive and our capacity to understand: see their debate in Allison (2000), Longuenesse (2005b). Somewhat surprisingly, neither difference matters for my purposes (see my further discussion of Longuenesse’s view in §3). [^]
  14. For this account, see Longuenesse (1998: 179, 358–70; 2005b: 24), Allison (2004: 249–52). [^]
  15. I think Longuenesse is implicitly aware of this obscurity, as she argues that the logical form of community is not, as Kant says, disjunction, but rather reciprocal hypotheticals: if A, then B and if B, then A (Longuenesse 1998: 390–91; 2005c: 201, nt. 23). This fits well with the data that would be available to be interpreted on her view, but what could sustain the reciprocal hypotheticals? We could, of course, reverse course, and start by perceiving A followed by B and then B followed by A. But, as we saw in §2.1, reversibility is neither necessary nor sufficient for Order-Indifference. In this connection, note that in her earlier account, Longuenesse understood Order-Indifference to mean reversibility, while in her later account she revises her position because she recognizes the problems with reversibility (see her correction at Longuenesse 2005a: 158 #2 and 161, esp. nt. 25). (Allison does not appear to appreciate the difference between Order-Indifference and reversibility: see his use of variables (Allison 2004: 264).) I suggest that Longuenesse herself came to realize the problem with reversibility but has not thoroughly assimilated that realization into her reading of the 3rd Analogy. [^]
  16. Perhaps the best defense of the interpreting theory would consist in denying the need for any favoring of one interpretation of another, with the idea being that we do in fact interpret the sequence in one way rather than another—and that we do so without reason is no problem for Kant’s aspirations. (Importantly, for this to qualify as an interpreting theory, we must still engage in some act of determining the data provided by mere perception to arrive at the representation of coexistence. This is important, because if one drops this idea, then the suggestion ceases to be different from my own view, and I would happily endorse it.) Doing justice to this version of the interpreting theory would take more space than I have here. I would like to sketch, however, the direction my response would go. The trouble I have with the view is not so much that our putative knowledge of the world would be no better justified than some rival putative knowledge; it is that I do not see how we can intelligibly speak any longer of interpreting the data made available through perception. Why, for instance, think of what we do as an interpretation of that data, rather than a different kind of procedure—a procedure in which we associate the data according to our habits? The data provides ‘insufficient friction,’ I would want to say, such that I no longer see how the interpretation qualifies as an interpretation of what is perceived rather than some other kind of response. My thanks to an anonymous reviewer for raising the objection I consider in the main paragraph as well as the one in this note. [^]
  17. Does Kant think that there are acts of mere perception? The argument of my article is neutral on this question: as I have just suggested, it is consistent with the claim that Kant thinks there are acts of mere perception; but it does not entail that Kant thinks there are. There are passages in which Kant does suggest there are acts of mere perception. For instance, in the 2nd Analogy, he talks about being ‘conscious that my imagination places one state before and the other after, not that the one state precedes the other in the object,’ and this consciousness would be consciousness of states that involves no objective time determination of those states (B233). One might argue that he only invokes that consciousness to show that it is not what we possess, as he introduces this idea in the course of explaining why the imagination does not provide a basis upon which one could ‘perceive that appearances succeed one another, i.e., that a state of things exists at one time the opposite of which existed in the previous state’ (B233). But it seems more plausible to me that he does endorse the possibility of mere perceptions. (My thanks to an anonymous reviewer for rightly suggesting I reconsider the passage from B233–34.) [^]
  18. This means that there will be a categorially significant perceptual difference between cases in which I perceive the coexistence of two states of one substance and the coexistence of two states of distinct substances. Where I perceptually determine that two states of one substance coexist, I determine those states as partial determinations of the existence of the substance (see A186/B229). Among other things, this involves ruling out that they are contraries: perceiving the same substance as both round and square is perceiving a succession of states in the substance; there is no such thing as perceiving the same substance to be simultaneously round and square. By contrast, when I perceptually determine that two states of distinct substances coexist, this does not involve ruling out that they are contraries. This difference is a difference in the manner in which I perceive: it is neither a consequence of the empirical matter/content of my perception, nor of a subsequent determination of those states on the basis of the matter/content of my perceptions. (My thanks to an anonymous reviewer for asking for clarification on this difference.) [^]
  19. It might help to say a word or two about how this connects to the objection that Kant’s answer to the ‘On the basis of what?’ question is unjustified, and in particular to the figure lurking in the background of this discussion: Hume. According to one traditional way of understanding Hume, he grants that we can perceptually discriminate between a case in which (it seems to us that) objects change and one in which (it seems to us that) objects stay the same. He then inquires into the conditions of how we do that, and whether our so doing has any objective validity, and argues that we make this distinction based only on our habit/custom and that we cannot find any objective ground for distinguishing between the two cases. This is not the only way to read Hume, of course, but here is not the place to wade into issues of Hume interpretation (for some evidence, see Hume 1978: 36, 74). If this way of reading Hume is correct, then Hume’s skeptical doubts are not directed either at my capacity to represent that states coexist or succeed, or at the thought that that representation is a perceptual one. His doubts are rather directed at finding any connections between the succeeding states I perceive as coexisting or successive, and he argues that we cannot find those connections in the content of our perception (on this point, cp. Rödl 2012: 115–16, 124). So, he would be forced to accept Kant’s starting point that my capacity to perceive is a capacity to perceive coexistence, in the sense that I do in fact perceptually discriminate between the case of the house and the case of the ship; where they differ is in their explanation of how I can do that: Hume appeals to my mental habits, while Kant appeals to objective (necessary and universal) time determinations. [^]
  20. I am indebted to Land (2015: 43) for my formulation of this point. The idea of being perceptually cognizant of something as such and such, or perceiving as, is most thoroughly developed by Sellars (who, unfortunately, does not seem to have offered any reading of Order-Indifference, or said much about the 3rd Analogy) (Sellars 1968: 1ff.). For a response, see Allais (2009). There may be senses in which, as Allais contends, I can perceive as such and such without possessing any concepts, but the sense of perceiving as such and such that I invoke puts the perceiver in a position to judge and so requires concepts. (Allais contends that Kant recognized no such perception. I am suggesting that attributing this kind of perception to Kant helps explain Order-Indifference.) [^]
  21. Conant (2016: 80). He adapts the term from an essay by Boyle (2016), while Boyle himself uses the term to gloss some suggestive remarks in McDowell’s Mind and World (McDowell 1996: 64). The view goes back, really, to Hegel’s account of Kant (Hegel 1986: 304ff., 328–30), but the list of modern defenders of the view has grown quite numerous. The most important defenses of it include: Engstrom (1994; 2006), Longuenesse (1998), Friedman (2000; 2012), Ginsborg (2008), Bauer (2012), Rödl (2012), Land (2014; 2015), Conant (2016), Newton (2016), Shaddock (2018), Williams (2018). To my knowledge, apart from Longuenesse, none of these authors have articulated a reading of the 3rd Analogy along the lines of their view (Friedman has discussed interaction, but not the argument of the 3rd Analogy). I will discuss Longuenesse’s version of the view below. Those interested in criticisms of the transformative reading of Kant should consult Allais (2009; 2015), McLear (2011), Tolley (2013), Allison (2015), McLear (2015), Onof and Schulting (2015), Golob (2016). Also salient to the debate are the essays contained in Heidemann (2013), Schulting (2016). My thanks to an anonymous reviewer for pressing me to further clarify the bearing of my argument on the conceptualism/non-conceptualism debate, especially in connection with Longuenesse. [^]
  22. For a particularly clear statement, see Longuenesse’s response to Sedgwick and Allison (Longuenesse 2005b: 25–26). In her language, the categories work in mere perception as guides for synthesis, but not as rules under which we can subsume the objects we merely perceive. See also Longuenesse (1998: 335), where she describes our apparent perceptual familiarity with the temporal determination of things as ‘deceptive.’ Grüne defends a similar view (cf. 2009). [^]
  23. She bases her view on Kant’s discussion of the transition from judgments of perception to judgments of experience in the Prolegomena, especially Kant’s claims that judgments of perception do not involve the categories and that all of our judgments start out as judgments of perception (Kant 1997: 4:298, §18). (For a recent, and to my mind persuasive, criticism of Longuenesse’s view, see Sethi 2020: 2–5). Kant’s distinction in the Prolegomena is developmental; hence, a (tenacious) reader can understand that development as necessary, such that the capacity to form judgments of perception is inseparable from the capacity to form judgments of experience. Such a reading would reconcile the transformative account I suggest in the text with Kant’s distinction. I admit, though, that Kant’s language of temporal development (‘at first’ our judgments are judgments of perception, becoming judgments of experiencing only ‘afterwards’) in the Prolegomena certainly suggests a less transformative conception, and this supports Longuenesse’s view (or a completely non-transformative view of Kant on perception, such as Sethi’s). [^]
  24. I presented drafts of this paper at a workshop on German Idealism at Yale in 2020, the Pacific Study Group for the North American Kant Society (NAKS) in 2021, and at a Virtual NAKS meeting in 2022, and I would like to thank the audiences of all three for their helpful comments. I would especially like to thank Stephen Engstrom and Sasha Newton for agreeing to be my ‘ideal commentators’ at the last mentioned event—my discussion of the synthesis of perceptions has been greatly improved by their suggestions. For reading drafts and helpful conversations, I would like to thank Jim Conant, Shana Crandell, Kay Dannenmaier, Thomas Land, James Messina, Andrew Pitel, Jessica Tizzard, Clinton Tolley, and Eric Watkins. [^]

Competing Interests

The author has no competing interests to declare.


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