Against Passage Illusionism

1. Introduction

We can all agree that it seems to us as though time passes in some purely trivial sense: namely the sense in which it seems as though it is now 1.30 PM, (say), and that it was, earlier, 10.30 AM. It seems as though some duration has elapsed between the former and the latter. Philosophers disagree, however, about whether it seems as though time passes in some more interesting, metaphysically robust, sense. Many have thought that it does seem this way. According to Schlesinger, “[t]here is hardly any experience that seems more persistently, or immediately given to us than the relentless flow of time” (1991: 427). Norton says that “Our sense of passage is our largely passive experience of a fact about the way time truly is, objectively” (2010: 24) and Savitt writes that “[i]t seems manifest in our experience that time flows—from the past, to the present moment, and into the future” (1996: 348). Le Poidevin writes that “we are not only aware of [the passage of time] when we reflect on our memories of what has happened. We just see time passing in front of us, in the movement of a second hand around a clock, or the falling of sand through an hourglass, or indeed any motion or change at all (2007: 76, my emphasis) and Schuster claims that “the flow of time, or passage, as it is known, is given in experience, that it is as indubitable an aspect of our perception of the world as the sights and sounds that come in upon us, even though it is not the peculiar property of a special sense” (1986: 695, my emphasis).

Let’s call the phenomenology that these philosophers take themselves to be describing, the target phenomenology.¹

In what follows I take the target phenomenology to be at least quasi-perceptual in nature.² By this I mean that either the state is perceptual in nature, or if it’s not, then many of the features of that state are shared by paradigmatic perceptual experiences, particularly experiences of change and motion. For instance, this state seems to involve the presentation as of mind-independent features of the world (as distinct from features of our experience) and the content of that state seems to involve the presentation of features of the world in such a way that the content is responsive to the character of the objects presented in experience (such as, for instance, events at times). This in contrast to, say, our experience of imagining a blue cow, which does not seem to be perceptual in either of these ways.

Many philosophers think that the target phenomenology is one in which it seems to us as though time robustly passes. I take this to be the claim that the target phenomenology not only has phenomenal character—there is something that it is like to be in that state—but also that it has phenomenal content. That is, the state represents the world as being thus and so.³ So according to these philosophers the state represents that time robustly passes,⁴ or, as I will say, has content as of robust passage.⁵ That is, it represents that our world is as temporal dynamists (i.e., A-theorists) suppose it to be: there is an objective fact as to which moment or set of events is present, and which moment or events that is, changes. I take this to be the view that the target phenomenology has a certain perceptual or quasi-perceptual phenomenal content that represents that time robustly passes.

The quotes at the beginning of this introduction are from authors who think the target phenomenology has phenomenal content as of robust passage, and those quotes are attempts to describe that phenomenology.

Unsurprisingly most temporal dynamists hold that the target phenomenology has content as of robust passage.⁶ They think that the world contains robust passage, and that is why we have veridical states that represent such passage.⁷

Phenomenal passage illusionists⁸ (henceforth just passage illusionists) agree that the target phenomenology has phenomenal content, and that the content is as of robust passage.⁹ But they hold that the content is illusory (i.e., non-veridical) because in fact time does not robustly pass.

Until recently passage illusionism was probably the most common view amongst non-dynamists, who include both B-theorists (see Maudlin 2007; Oaklander 2012; Mellor 1998; Le Poidevin 1991) and C-theorists (see Price 1996; Farr 2012; 2020a). More recently, however, some non-dynamists have rejected passage illusionism in favour of the view that the target phenomenology has some other, veridical, phenomenal content (Deng 2013; Farr 2020b;¹⁰ Frischhut 2015; Bardon 2013). Call this the veridical passage-less view.

At this point an important clarification is in order. According to the veridical passage-less view we do not have experiences as of robust passage. Instead, our experiences veridically represent aspects of our non-dynamical world. Sometimes such views are presented as ones on which there is no sense at all in which it seems to us as though time flows, or passes, or is dynamical. This is not what I intend. For instance, Sattig (2019b) describes his view as an account of our experience of temporal flow/passage, although it is a view that is compatible with our world being non-dynamical and yet us not being subject to any illusion. So it is a veridical passage-less view in my terminology. Deng’s (2013) view is one on which we have experiences that represent anodyne passage, and Leininger’s (2021) is one on which we have experiences that represent B-passage. Anodyne and B-passage are both ‘passage’ that is not robust and can obtain in non-dynamical worlds. Yet both of their views count as veridical passage-less views given my terminology.

So, when I talk of veridical passage-less views I intend only the following: these are views on which it does not seem to us, in experience, as though time robustly passes: our experiences do not represent that our world is A-theoretic/temporally dynamical. Thus, by parity, the view I call passage illusionism is the view that we are subject to an illusion in which it seems as though time robustly passes.

One notable version of the veridical passage-less view is known as the cognitive error view, since it holds that although we in fact have phenomenology with a veridical content, we tend to mistakenly believe that the phenomenology has content as of robust passage (Hoerl 2014; Miller, Holcombe, & Latham 2020; Miller 2019; Baron & Miller 2018). While other versions of the veridical passage-less view have been less well explored, another fairly natural proposal is that not only does the target phenomenology have veridical content, but there is no error anywhere: we don’t even misdescribe the phenomenology.¹¹ Rather, at best there is a philosophical error that some people make, which is to believe that we describe our phenomenology as being as of passage. Some recent empirical work suggests that this might be so (Latham, Miller, & Norton 2020a).¹²¹³

In what follows I argue against passage illusionism. In doing so I take myself to be providing reasons in favour of a veridical passage-less view.

I assume that our world does not contain robust passage. Given this, I argue, non-dynamists should deny that the content of the target phenomenology is as of robust passage, and hence should reject passage illusionism.

First, (§2) I distinguish two broad classes of view the non-dynamist might take about the target phenomenology: detection vs non-detection views. According to detection views the target phenomenology is the product of the functioning of some capacity or capacities to detect features of the world. According to non-detection views it is not. I argue that non-dynamists in general, and passage illusionists in particular, will (and should) endorse the former over the latter. So the remainder of the paper focuses on detection-view versions of passage illusionism. In §3 I introduce two strategies that the passage illusionist might adopt in attempting to explain how we come to have an illusory phenomenal state: representational modesty and representational immodesty. §§4–5 then argue that whether the passage illusionist endorses representational modesty (§4) or immodesty (§5) she will have difficulty explaining how we come to have a state with illusory content as of robust passage. I conclude that we have reason to reject passage illusionism in favour of veridical passage-less views.

2. Detection vs Non-Detection Views

Passage illusionists hold that it seems to us as though time robustly passes. So, they hold that we have phenomenology with a certain phenomenal character. In what follows I make no assumption that the phenomenal character of the target phenomenology is exhausted by its phenomenal content (though of course representationalists about character will think this is so). Perhaps there are some aspects of the way things seem to us, in this regard, which either have no determinate content—there is no fact of the matter what they represent—or in which the seeming is in no sense represented as being a feature of the world itself. Torrengo (2017) for instance, thinks this is so: he thinks we have phenomenology with a certain ‘flowy’ phenomenal character, but that we do not represent that time flows because it does not seem to us as though this flowiness is a feature of the world rather than of our experience.¹⁴ For all I say there may be such seemings, and they may sometimes lead us to utter sentences such as ‘time flows’. But if those aspects of phenomenal character are like this, then whatever their character it cannot be that by having those experiences it seems to us as though time flows. Its seeming that way, if it does, is a matter of our being in a state with phenomenal content, which is why that is what I focus on here.

One might wonder: how can there be any debate about the content of the target phenomenology? After all, lots of people introspect that phenomenology and claim that it seems as though time robustly passes. Surely we should think that this is how it seems to them. Before proceeding it’s worth saying something about why I think this way of determining the content of that state is poor.

First, even setting aside general worries one might have about the reliability of introspection, there are reasons to worry about this method. The descriptions of the target phenomenology found at the beginning of this paper all look quite different, despite the fact that their authors all think they are describing a state whose content is as of robust passage. If we were to include the sorts of descriptions that non-dynamists make of their phenomenology we would get even more divergent descriptions.

Indeed, when we look at empirical research on the ways in which people describe the target phenomenology we find huge differences. For instance, in a study by Latham, Miller and Norton (2020a) we find that ~40% of people strongly agree that it seems to them as though the future is ahead of them and moving towards them, while ~11% strongly disagree that it seems this way, and ~50% neither strongly agree nor disagree. We find similar variation across all the sentences with which participants were presented.

Moreover, since some philosophers have argued that the way we describe the target phenomenology is a product of different theoretical commitments about the nature of time (Braddon-Mitchell 2013), or of different, perhaps implicit, ways of conceiving of time (Latham, Miller, & Norton 2020a), or of using different linguistic or conceptual resources (Miller, Holcombe, & Latham 2020) there is a concern that people will differently describe the target phenomenology. So appealing to their introspected descriptions seems like a poor way to determine the target’s content.

At any rate, even after introspecting, non-dynamists still disagree about whether the target phenomenology represents robust passage. So I take this to be an open question.

Illusionists face a burden: they need to explain how it is that we come to have a phenomenal state with illusory content. This is particularly pressing in the case of passage illusionism, since passage illusionists hold that we are subject to a persistent and pervasive illusion (unlike most perceptual illusions) and, further, that the illusory state has representational content as of something that does not actually obtain (and indeed, on some views, as of something impossible). Making sense of how we could be subject to that kind of illusion with that kind of content is what Hoerl (2014) calls the intelligibility problem.¹⁵

There are two broad options the passage illusionist might adopt to provide a solution to the intelligibility problem. The first is the detection view. According to that view the illusion as of passage is the product of the functioning of some mechanism(s) whose function is to detect some feature(s) of the environment. When exercising a capacity, C, is typically accompanied by some phenomenal state, I will talk of the phenomenal state as of exercising C. Then the detection view has it that there is some capacity, or set of capacities, such that the representational content of the phenomenal state as of exercising that capacity or set of capacities is the target phenomenology. The passage illusionist version of this view simply adds to this the claim that the target phenomenology has content as of robust passage.

The other view is the non-detection view. This is the view that the target phenomenology is not the product of exercising any capacity to detect a feature of the world. Rather, the target phenomenology in some sense floats free of our exercise of any capacities. As far as I know, no one has such a view and, I think, for good reason.

I noted earlier that the target phenomenology is taken to be at least quasi-perceptual in nature. So regardless of whether one thinks that the target phenomenology has illusory or veridical content, it is very natural to suppose that the state is the product of the functioning of one or more capacities that allow us (perceptually) to detect features of the environment.

The passage illusionist has further reason to suppose this to be so. The explanation of perceptual illusions typically proceeds via an appeal to various capacities and mechanisms that allow us to detect environmental features.

For instance the Müller-Lyer illusion, in which it (mistakenly) appears as though one line is longer than the other, is the product of the fact that the angles on the lines act as depth cues that we associate with three-dimensional scenes. We (or our cognitive systems) then mistakenly view the image as a three-dimensional drawing. A size constancy mechanism, which is a mechanism that allows us to see some objects as being further away, rather than smaller, makes us think that one of the lines is longer. That is because, were the drawing three-dimensional, that line would be further away and hence would, in fact, be longer than the other line. So this illusion is the product of perceptual mechanisms that detect three-dimensional shapes at various distances from us.

The point generalizes to other perceptual illusions. The illusion of apparent motion is the product of certain features of our motion detecting sensors. The Chubb illusion (in which objects appear to have more contrast when placed on high-contrast textured background) is thought to be the product of our capacity to detect objects in ambiguous conditions (such as from a distance or through smoke or fog).¹⁶ Similar considerations apply to Adelson’s shadow illusion,¹⁷ and Poggendorff illusion.¹⁸

Since the passage illusionist thinks that the target phenomenology has illusory content, it makes sense for her to try to explain its content by appealing to the functioning of such mechanisms.

The most plausible version of the detection view is what I call the temporal detection view. On this view the functioning of mechanism(s) that ground our having certain temporal capacities—capacities to detect features of time, or time-related phenomena—are responsible for the illusion as of passage.

Here, I use ‘temporal capacity’ fairly broadly, to include both detecting temporal relations (such as order and duration) and also time-related capacities such as the capacity to detect motion and change, as well as the capacity to mentally time travel (and several others).

Then according to the temporal detection view exercising one or more of these temporal capacities is associated with a representation of robust passage, where that content is the content of the phenomenology as of robust passage.

In what follows I will suppose that the passage illusionist accepts the temporal detection view. Hence her aim is to locate certain temporal capacities that could singly or jointly be associated with a phenomenology as of robust passage.¹⁹

The remainder of the paper argues that on the assumption that time does not robustly pass, we should think that the phenomenology associated with the functioning of these temporal capacities, singly or jointly, does not have content as of robust passage.

To make this case I will consider two strategies that the passage illusionist who accepts the temporal detection view might adopt in order to respond to the intelligibility problem.

The first is to accept what I call representational modesty, and the second is to accept representational immodesty. I’ll argue that whichever route the passage illusionist takes she fails to have a satisfactory account of how we could come to have a state with content as of robust passage.

3. Two Strategies for the Passage Illusionist

The first strategy the passage illusionist might adopt is representational modesty about the representations that issue from exercising temporal capacities. On this view, when we exercise a capacity to detect some temporal feature F, the resulting representation does not have content that is richer than F. That is, the content does not represent F plus G, where G is entirely distinct from F.²⁰ So for instance if representational modesty about the representations that issue from exercising temporal capacities is true, then when we exercise a capacity to detect temporal order we have a state whose representational content is not richer than a representation of temporal order. That is, the state does not both represent temporal order (F), as well as representing something else (G), that is entirely distinct from F.

The alternative view is representational immodesty about the representations that issue from exercising at least some of the temporal capacities. On that view, at least sometimes when we exercise a capacity to detect some temporal feature F, the resulting representation has content that is richer than F. That is, the resulting content is F plus G, where G is entirely distinct from F.

Representational immodesty about the representations that issue from exercising some non-temporal capacities has been defended. Chalmers (2006), for instance, argues that our ocular systems detect reflectance profiles. What we represent, however, are not merely reflectance profiles. We don’t merely represent that objects are coloured. In addition, we represent that colour properties are intrinsic to objects, and that those intrinsic properties are evenly distributed across the surface of objects. Reflectance profiles are not intrinsic to objects, nor are they evenly distributed across the surface of objects. So, according to Chalmers, the content of our colour representations is richer than what the mechanism in question detects; our representations attribute to the world properties that it does not have: intrinsic evenly distributed colour properties. Other examples suggest themselves. Perhaps we have a mechanism for detecting the solidity of objects. And perhaps the functioning of that mechanism generates a representation of solidity that represents that solid things are composed of continuous matter. If so, then representations that issue from exercising the capacity to detect solidity are immodest.

Here is a general motivation for representational modesty about the representations that issue from exercising capacities. We have mechanisms that evolved to allow us to detect things in our environment: faces, predators, food, and so on. At least in part, the way that mental states get to have the content they do is by co-varying with the states of the world they represent.²¹ So it is natural to think that when a mechanism that evolved to detect feature F generates some representation, that it generates a representation whose content is not richer than F. Face detection mechanisms detect faces, and thereby represent faces. They don’t represent faces plus something else as well.

Importantly, though, representational modesty about the exercise of some capacities is not the view that whenever we exercise those capacities, the content of the resulting representation is not richer than the state of the world that triggered the exercise of the capacity. So being representationally modest about the exercise of some capacities is consistent with holding that sometimes when we exercise those capacities the resulting representation is illusory.

To see this, consider our facial detection mechanism. That mechanism evolved to allow us to detect faces. A defender of representational modesty about the representations that issue from the functioning of this capacity will say that when we exercise that capacity to detect faces, the resulting representation is not richer than a representation of a face. That, however, is consistent with us sometimes representing there to be a face where there is none.

Our facial detection mechanisms are in fact very sensitive. They often signal the presence of a face when all that exists are various lines arranged in certain ways. We ‘see’ a face in the clouds, or on a piece of toast. The friend of representational modesty can think that when we see the face in the sky we are subject to a perceptual illusion. We see something that is not there. But it is still the case that when we exercise the capacity to detect faces, as we do when we see a face in the clouds, the resulting representation does not have content that is richer than a representation of a face.

Representational immodesty about the representations that issue from the capacity to detect faces is the view that when we exercise the capacity to detect faces we at least sometimes not only represent a face, but also represent something that is entirely distinct from a face. That is, the resulting representation is richer in content than a representation of a face.

In general, representational modesty is perfectly compatible with accounting for perceptual illusions. We’ve just seen how it can account for the illusion as of a face in the sky, or on some toast. Similar things can be said to explain, say, the Muller-Lyer illusion using a representationally modest view of the relevant representations. In fact, all of the explanations of perceptual illusions I am aware of are ones that trade on the representations in question being modest.

What endorsing representational modesty about the representations that issue from the exercise of various capacities does do, however, is make it difficult to see how we could have perceptual/quasi-perceptual representations with content that represents something that does not exist. In general that should strike you as welcome: it’s hard to see how any mechanism could evolve with the aim of detecting some non-existent feature of the world, and hence hard to see why any mechanism would systematically generate perceptual or quasi-perceptual representations of that non-existent thing. But that being so will be a problem for the passage illusionist.

Here is why. If the passage illusionist endorses representational modesty then she will hold that the representations that issue from exercising temporal capacities do not have content that is richer than what those capacities detect. On the assumption that there is no robust passage, none of these capacities detect robust passage. So none of the content of the representations that issue from the exercise of those capacities will be content as of robust passage.

So, one might think, for better or worse the passage illusionist must reject representational modesty.

Indeed, I think that passage illusionists have traditionally taken the route of endorsing representational immodesty. Many passage illusionists have connected the phenomenology as of time robustly passing with the phenomenology as of motion and change, holding that the phenomenology as of robust passage just is the phenomenology associated with our perceiving motion and change.²² For instance Dainton (2012) holds that in perceiving motion/change we do not simply perceive things as (in the case of motion) occupying different places at different times—which is in fact what motion consists in, in a non-dynamical world—but rather, we see them as having some special dynamical quality that is something over and above perceiving things as being in different places at different times. This suggests an immodest view on which our capacities to detect motion/change do not only represent motion/change (by representing a difference in relative location), but also, they represent something more, something which does not in fact obtain. As Dainton puts it “in a quite general way, our perceptions of moving objects . . . are associated with distinctively dynamical sensible appearances, sui generis forms of experience which are not reducible to (or composed of) sequences of static appearances” (2012: 127). Thus, it seems, our perceptions of motion (at least) have representationally immodest content. They represent not just motion, but something else: this sui generis dynamical sensible appearance. Then, as Dainton puts it “our perceptual systems are responsible for creating the dynamical qualities that we perceive moving objects as possessing” (2012: 127).

Part of what motivates this idea is the appeal to (inter alia) motion illusions. Both Dainton (2012) and Paul (2010) point to the fact that we are subject to the appearance as of this dynamical quality of movement even when there is no moving object at all (as for instance in cases of apparent motion). The idea is that if we can have experiences as of this dynamical quality in the absence of any real motion at all, this suggests that the experience is the product of some mental process that ‘paints onto’ the world qualities that it does not have. For instance, Paul argues that illusions such as that of apparent motion show that our cognitive systems “represent the situations as though there is an animated qualitative change in a dot from red to green” (2010: 351) even though actually there are just two stationary dots; one red and one green. Again, here, the idea seems to be that our cognitive systems generate the perceptual illusion not by, say, combining representationally modest representations in such a way as to create an illusory perception, but rather, by our having representationally immodest perceptions of motion and change.

Similarly, Prosser (2016) holds that when we perceptually experience motion and change we experience perduring objects as enduring: we misrepresent the way perceived objects persist through time. It seems most natural to interpret this as the view that the representation that issues from exercising a certain capacity—namely the capacity to detect stages of perduring objects—issues in content that is richer than what that capacity detects, by representing that the stage it detects at one time is numerically identical with the stage it detects at another time. Hence it represents that objects endure, by producing immodest representations.²³

Although passage illusionists have tended to embrace representational immodesty, it is not obvious that they need do so. Indeed, for my purposes it doesn’t really matter which view the passage illusionist endorses, since in what follows I argue that passage illusionism is implausible whichever way it is spelled out.

But it is worth noticing that passage illusionism is not incompatible with representational modesty. It could be that although none of the representations that issue from exercising capacities to detect some temporal feature, F, have content that is richer than F, nevertheless there is a perceptual or quasi-perceptual state that combines these contents and which has illusory content as of robust passage.

After all, consider how it is that we are able to represent things that do not exist, and perhaps even things that could not exist. A plausible suggestion is that we do so by combining representational elements that have the content they do in virtue of co-varying with states of the world. So for instance, we come to represent flying horses, or unicorns, by combining representational elements—horses, wings, horns—that co-vary with horses, wings and horns and in virtue of that have the content they do.

Now, these kinds of representations are usually not perceptual or quasi-perceptual. We imagine a flying horse or a unicorn; we don’t seem to see them. It’s harder to see how this would work when it comes to perceptual or quasi-perceptual content.

But consider Escher’s Relativity. Plausibly, in seeing that piece of art we have a perceptual state that is illusory in the following sense: it seems to us as though we are seeing an impossible topology. Since there are no impossible topologies, in some sense what we are seeing is illusory. An obvious explanation for our having a state with that content is that we combine various veridical perceptual contents of, say, staircases, in a way that generates the illusory perceptual content.

Regardless of whether you think this is what is going on when we see Relativity, the passage illusionist might try to tell an analogous story on which the illusion of robust passage is the product of combining representations that issue from exercising various temporal capacities, where those representations are modest. In what follows, however, I argue that no such story is likely to succeed.

4. Illusory Passage and Representational Modesty

A passage illusionist who embraces representational modesty needs to show how putting together representational contents that issue from the exercise of temporal capacities and whose content is not richer than what those capacities detect, can nevertheless issue in a perceptual/quasi-perceptual representation as of robust passage.

In order to see how she might do this, we need to get a better sense of the various contents to which she has access. I will outline these in the next section by focusing on various capacities that we have to detect aspects of our world. I assume that in exercising these capacities we have perceptual or quasi-perceptual states with certain contents, and that these contents are candidates to be ones that might, jointly, issue in a perceptual or quasi-perceptual representation as of robust passage.

5. Representational Immodesty and Illusory Content

I do not find representational immodesty very appealing. We have many perceptual mechanisms that allow us to detect things in our environment, and in some environments those mechanisms function to signal the presence of something—a face, a predator, lines of different length—where there is no such thing. Thus we are subject to perceptual illusions. That can hardly be surprising. I find it much more surprising that we would have a mechanism that is evolved to detect a certain feature of our environment, say colour, where the output of that mechanism is a representation with content that is richer than what it detects, say, intrinsic evenly distributed colour properties. So I, at least, take it to be a cost of passage illusionism if the view is only plausible given representational immodesty. This, however, is not the place to argue against immodesty.

Instead, let us suppose that the passage illusionist is representationally immodest, and hence holds that at least some of the representations that issue from the exercise of some of the temporal capacities are such that their content is richer than the features that those capacities detect. Then there remains the task of showing where the illusory content comes from.

The most obvious place to start, in answering this question, is to consider extant views articulated by passage illusionists. To that end, let’s return to Dainton (2012) and Paul (2010). Their idea, recall, is that in perceiving motion and change we have experiences with dynamical content that is richer than the content associated with the detection of motion and change. What, though, is this additional immodest content? Well in part, what motivates such views is the idea that it does not simply seem to us in experience as though we see a series of static images of objects either located at different places (motion) or having different properties at different times (change). Rather, we see things move and change, and seeing this is seeing something over and above what we in fact detect.

Now, I don’t think it’s obvious that in order to make sense of our phenomenology of motion/change we need to think that our representations of those phenomena are immodest: that they attribute to the world some dynamical property that is not there. But suppose we do. Can we get from this to the idea that we have experiences as of robust passage? Not obviously. To be sure, we get to say that our perceptual experiences have a sort of dynamical quality to them, and that this quality is illusory. But it is not really very plausible that that content is one as of robust passage. To see this, suppose our world is non-dynamical. It contains moving things, which is to say that it contains things that are located at different places at different times. In perceiving such things, though, we perceive those things as moving, rather than simply as being in different places at different times. Likewise, when we perceive change we perceive things as changing, rather than just perceiving things as being one way at one time, and a different way at a different time. Whatever exactly the (immodest) content of this perception of motion and change is meant to be, it doesn’t seem to involve there being a metaphysically privileged present which changes. Whatever the additional immodest content is, in this case, it is very unclear that that content is as of robust passage.

Quite generally, it seems that what is missing in this story, and indeed what was missing from the story offered by the friend of modesty, is the presence of a representation of objective presentness. Why does a representation of robust passage need to involve a representation of objective presentness? Robust passage is the change in which events are objectively present. It is not, for instance, the mere change in which events are subjectively, or perspectivally, present. Even those who reject robust passage think that in some good sense there is a change in which events are subjectively present. So if it is true that we have perceptual experiences that represent robust passage, as opposed to representing something else (such as anodyne passage that can obtain in non-dynamical worlds) then it must be that the experience in question represents the movement of objective presentness.

It seems clear that associated with the exercise of temporal capacities we have modest (or indeed immodest) representations of change, motion and either indexical presentness or what we might call simple presentness (where this is just what we have when we have untensed perceptions, or perceptions with no temporal viewpoint). And while some of these might be illusory (if Paul and Dainton are to be believed regarding motion/change) they are not sufficient to explain why it seems to us as though time robustly passes, as opposed to its merely seeming to us as though things move and change. So these views are better thought of as views that are more similar to that of Prosser, on which the target phenomenology is one whose content is (at least in part) illusory, but where the content of that illusion is not a representation of robust passage, but rather, is some other non-veridical content.

This, of course, is no help to the passage illusionist. If what I have said so far is right, then the passage illusionist needs to explain how and why it is that, singly or jointly, the exercise of the temporal capacities issues in an immodest representation of objective presentness (and its movement).

I’m unclear how such a story would proceed. I can see how we might go about telling that story in the case of colour immodesty.

We have perceptual mechanisms for detecting things in our environment. As it turns out, it is often the case that the properties we detect are intrinsic to the objects in question. Moreover, sometimes even when they are not intrinsic, for all practical purposes we can treat them as though they are. Consider for instance weight. Weight is not intrinsic. But we can treat it as such given that we are all Earth bound. Colour is the same.

It surely matters to organisms whether properties can be treated as intrinsic or should be treated as extrinsic. If gravity varied a good deal across local regions of the earth, organisms would need to treat weight as extrinsic. So we’d expect mechanisms to detect whether a property can reliably be treated as intrinsic or extrinsic, and to label it as intrinsic where the answer is yes, and as extrinsic otherwise. So when a property can reliably be treated as intrinsic we might expect it to be represented as intrinsic.

Since we can reliably treat colour as intrinsic this could explain why our colour detection mechanism represents colours as intrinsic (if indeed they do). Mutatis mutandis for weight.

It’s a good deal harder to imagine why any mechanism that detects temporal capacities would come to represent objective presentness. Neither a representation of indexical presentness (if we have one) nor of simple presentness (if we have one) is a representation of objective presentness. We have already seen that if we represent simple presentness, and we represent that our experiences are ‘replaced’ (as per Sattig’s suggestion) then we get a veridical passage-less view. In order to ‘upgrade’ that view to a view on which we represent robust passage, then, it needs to be not only that we, say, have perceptual experiences and that these have no temporal viewpoint, and that we represent that these experiences undergo replacement, but, in addition, it needs to be that we represent (in some manner or other) that these perceptual experiences are metaphysically special in some way, for instance by being the only experiences there are, simpliciter. The same is true, mutatis mutandis, of indexical presentness.

Why, though, would we represent objective presentness (given that there is no such thing in a non-dynamical world)? It’s hard to imagine that we would. Representing objective presentness is conceptually complex. It requires representing that certain events are metaphysically special by having some property (primitive or otherwise) that all other events lack. We could represent this by representing that present events are the only events that exist. This requires representing that there are events that did, or will, exist, but which do not exist. (Notice that simply having perceptual experiences that lack a viewpoint is not sufficient for this). Or we could represent this by representing that all events exist, but that some have a primitive property of presentness. These representations, however, are pretty sophisticated.

By contrast, in order to represent that some events are indexically present one only needs to represent that those events occur at this time, or with me now. One does not need to represent past or future events, let alone to represent either that those events did exist, (or will exist) but do not, or that they do exist but lack some special property. Likewise, in order to represent that things are simply present, one just needs to perceptually represent some things.

Given the conceptual complexity of representing objective presentness, and the fact that we gain nothing by doing so, it’s hard to see why any of our temporal mechanisms would immodestly represent objective presentness.

The unlikelihood of this is particularly striking when you consider that the target phenomenology is taken to be pervasive. This strongly suggests that the mechanisms responsible for that phenomenology will be relatively low-level sub-personal mechanisms that function autonomously and continuously without personal-level monitoring.

In turn, it seems very likely that such mechanisms will be found in creatures with reasonably sophisticated perceptual systems. Low-level mechanisms are typically shared across species. Moreover, we know that many animals keep track of time, and inter alia, are able to judge duration.³³ So it is likely that the mechanisms that subserve the capacities whose exercise is associated with the target phenomenology in humans will be shared across other species. I find it independently plausible that the target phenomenology is one that is found across a range of species. I would be astonished if Annie the labradoodle does not have the target phenomenology.

But if it struck you as doubtful that the exercise of any of the temporal mechanisms in humans is associated with an immodest representation of objective presentness, it should strike you as even more doubtful that this is so in dogs, pigs, and sugar gliders. Annie the labradoodle is quite sophisticated in a lot of ways. I am, however, quite confident that she does not represent objective presentness. This gives me reason to think that neither do you or I.

What might the friend of passage illusionism say at this point? Well, she might protest that we do have reason to treat present events as objectively present in the sense that we can reliably treat it as an objective matter whether or not two events really do occur at the same time, and hence whether they really are present (indexically or simply). That is because none of us is travelling sufficiently fast relative to anyone else that the sorts of relativities in temporal orderings that we see at high speeds (and which are captured by special relativity) are made manifest. So it makes good sense for our detection mechanisms to treat it as an objective matter whether two events are simultaneous.

So there may be a story about how we would come to have a certain kind of immodest representation: namely, a story about why a mechanism that detects simultaneity could issue in a representation that is richer than a representation of simultaneity by being a representation of objective simultaneity.

But even if that is so (and it’s far from obvious it is) representing that some events are objectively simultaneous is not sufficient to represent objective presentness. A world can contain objective simultaneity without thereby containing objective presentness. Had our world been a Newtonian block universe world it would have been a world in which there is a single preferred foliation of space-time into time-like and space-like slices, such that there is a fact of the matter regarding whether two events really are simultaneous. In such a world simultaneity is objective. But there is no robust passage since none of the time-like slices is singled out as being the one true present. Hence there is no objective presentness that moves. So representing that some events are objectively simultaneous is not to represent that some events are objectively present. Even if the passage illusionist can tell a story on which we perceptually represent certain events as objectively simultaneous (as opposed to merely representing that they occur at the same time, which would appear to require having the conceptual resources to represent that events can be merely subjectively simultaneous, and I am sceptical that this is so) and, further, we represent those events as either indexically or simply present, and, further, we represent that those very perceptual experiences are replaced with new ones, this still does not constitute our representing robust passage.

So here is where we are. Even if the passage illusionist embraces representational immodesty, I do not think she has a plausible story about how we come to have experiences that represent robust passage, even if she has a plausible story about how we come to have experiences with some illusory content. If that is right, then even with representational immodesty on the table we should reject passage illusionism. The burden, then, is on the passage illusionist to provide some account of why the various immodest contents that she posits are both (a) plausibly the product of the mechanisms in question and (b) really do issue, singly or jointly, in a phenomenal state that represents robust passage. In the absence of such an account we should think that most likely we do not have a state with phenomenal content as of robust passage. This leaves open that we might have a state with some other illusory content, or that we might have a state with veridical content; it also leaves open whether the veridical content in question is ‘thin’ and deflationary, or instead in some way answers to the description of being dynamical or flowy, despite not having content as of robust passage (and despite being veridical in a non-dynamical world.)