Category Archives: Ecological psychology

Are we wrong to believe we have separate senses?


A bird in flight must control its movement with reference to multiple simultaneous sources of information: air mass, the ground plane, changes in stimulation caused by its own movements (image)

Eyes are for seeing and noses are for smelling. Everyone knows this. You know this. But hold on, what’s this? Ecological psychologists think you’re wrong!

The problem goes like this. Animals have to move about in an environment that already has other stuff in it besides the animal itself. All kinds of stuff. Imagine you’re a fish. You want to get over there to swallow that clod of plankton. If this was a video game you’d just press buttons until the plankton clod got big and filled up the screen. And when you can’t make the plankton clod look any bigger, that’s when you know you’ve arrived. Good old-fashioned visually-guided locomotion. But things aren’t that simple. You’re a fish, and there’s water in the way. Now you also have to move in such a way as to cancel out the movement of the water. Also, since you’re a fish, that is, a living, active organism, the visual scene before your eyes is in part structured by your own movements. Now you have to work out which bits of the stuff you’re looking at are moving because stuff out there is moving, and which bits are moving because you’re a fish and you’re twitching your face from side to side and your paddling is creating weird ripples and shadows.

One way to respond to this is to shrug and say, “I dunno, being a fish is complicated, I guess. At least they don’t have to worry about table manners or heights.” This is the normal way to respond. If you’re an ecological psychologist, however, you might respond differently. You might come out with something like this: “We propose that the senses form a single, unitary, irreducible perceptual system whose sole function is to detect parameters of the global array.”

In making this proposal, Stoffregen, Mantel, and Bardy are doing us a service for they are forcing us to question an unexamined assumption. In this case, the assumption is that the senses constitute distinct and separate systems. As the authors note, James J. Gibson also liked to question unexamined assumptions. But Gibson himself accepted this particular assumption without examining it. According to SMB, this has led to problems. One such problem: research within the ecological tradition has asked questions of the form, “What visual parameter is implicated in controlling the movement of this seabird into this body of water?” But this reductively detaches the visual component of the behaviour from everything else that is going on in the bird–air–water–gravity–etc. system.

A more esoteric problem is this: specification of structure in the environment into structure in perception does not work if we consider the senses as distinct systems. If all the seabird has to go on is vision, then it has no way of distinguishing between changes in the appearance of the water surface that are caused by its movements towards the surface, and those that are caused by the movement of the air relative to the same surface. Without being able to distinguish between these, SMB claim, the bird cannot adjust its behaviour over time in the appropriate way. Specification only works if we consider all of the relevant structure at once. And we need specification. Ambiguity is no good. If specification fails, then direct perception is also impossible, and ecological psychology itself disintegrates into an incoherent puddle.

Now, it is tempting to respond to SMB’s proposal that the senses constitute a single, unitary system in this manner: “Nuh-uhh! The senses are obviously separate! Look! Eyeballs!” But SMB have been making this argument for a few years now and have apparently come across this response before (S&B originally published this argument in BBS in 2001; the 2017 paper is largely a reassertion of that one). The authors call for their critics to go beyond merely pointing out apparent instances of counter-evidence and to engage with their arguments “at the level of general principles”. So let’s try to do that. I will make three points.

First, while every assumption deserves to come under scrutiny once in a while, it’s impossible to evaluate any given assumption except in the light of remaining assumptions that we hold to be more fundamental or secure. Thus, SMB state:

If we accept that perception yields knowledge (i.e., that perception is epistemological), then we can ask what type of knowledge is obtained. Following Darwinian principles … Gibson reasoned that perception yields (and should yield) knowledge about the environment.

But wait, what? Why should we accept this assumption? I mean, not to be rude, but “perception yields knowledge”… that sounds a little, I dunno, Cartesian? SMB also talk about perception as having content: “Our focus is on the animal–environment interaction as the contents of perception”.

Maybe the real problematic assumption here is this one: that information is contentful, i.e. that it is about structure in the environment. This argument was made by Van Dijk, Withagen, & Bongers in a paper that I blogged about here.  If information is contentless, then the issue of ambiguity does not arise. Ambiguity is not in the information because information is not being transmitted. The animal is not in the business of constructing knowledge about what the world has in it. Rather, the animal is in the business of regulating the fit between itself and its environment. If this is the case then perception does not have to be infallible, it just has to be good enough to keep the animal alive for a certain while. The fit is either maintained, in which case the animal is still alive, or it isn’t, and it’s dead. But why say that this fit is the content of perception?

Second, in their enthusiasm to do violence to the Aristotelian dogma of separate senses, SMB sometimes risk doing damage to other theoretical distinctions which we presumably want to maintain. For instance, it seems useful to distinguish between a) action and b) structure in the environment with reference to which that action is being regulated. In their more effusive moments SMB seem to want to fold this all together:

The global array is not ambient to massless, geometric points; rather, it intrinsically, inescapably is ambient to and provides information about the full dynamics of the animal–environment interaction. The global array pulses with the life of the organism; it embodies animal–environment reciprocity.

SMB argue that Gibson’s notion of the ambient optic array as a set of points of potential observation is “disembodied” and “reductionist”, and we should instead think in terms of an “embodied point of observation”. We should recognize that visual information in real life is structured simultaneously by stuff in the environment and by the activities of the living, moving animal itself. When you walk, your eyeballs jiggle in your head, which is going up and down on top of your neck thump-te-thump. This is fine, but don’t we also still want to be able to talk about structure that’s actually out there in a straightforward way, without constantly having to talk about it in terms of the animal–environment fit?

Third, and more generally: suppose we all went along with SMB and just admitted that the notion of separate senses is mere superstitious hokum and baloney that has been holding us back from pursuing a properly scientific study of perception. Where would that actually get us? In what way is it useful to treat perception as a single system? It certainly seems useful to treat vision, say, as a distinct system. To do so is consistent with our everyday conception of our experience—our way of talking about it. Don’t we want to be able to explain, say, the navigability of the inside of a building in terms of what it looks like without having to also talk about what the air feels like on our faces or what smells are wafting in from a nearby cafeteria? How does it help us to flat out deny the distinctions we have traditionally made between the senses?

It’s hard to see the global array concept getting any real uptake based only on arguments that have been presented so far. What would make the case more convincing? SMB need to show either that the assumption of distinct senses is pernicious and has misled us in important ways, or that rejecting the assumption leads to useful outcomes or applications that would otherwise be inaccessible to us. They have done neither of these so far. Maybe they’re right, though. I’m going to ask a fish.


Stoffregen, T. A., Mantel, B., & Bardy, B. G. (2017) The senses considered as one perceptual system. Ecological Psychology, 29(3):165–197 doi: 10.1080/10407413.2017.1331116



Overcoming loser philosophy: Comments on Käufer and Chemero’s Phenomenology: An Introduction

If you are studying affordances, or studying the role of the body in perception and cognition, then you ‘are not merely influenced by phenomenology,’ you are ‘doing phenomenology, insofar as [you] are pursuing the basic ideas and insights this tradition was founded on.’ So claim Stephan Käufer and Tony Chemero (K&C) at the start of their new bookPhenomenology: An Introduction (2015).

Now, one would be forgiven for thinking it’s safe to ignore this book, on the grounds that a) it’s got the word ‘Phenomenology’ in the title, and b) it’s got the words ‘An Introduction’ in the title. But don’t let’s get hung up on those two details. K&C are pursuing a serious project here. They aim to show that the phenomenological tradition is alive, and that it provides the necessary foundation for embodied cognition research. The message of the book might be summarized thus: Nothing in embodied cognition makes sense except in the light of lived experience. It’s a good message, and I hope people take notice.

I am not going to summarize, in this post, all of the book’s discussion of the history of phenomenology. The book does a nice job of covering the major thinkers while also weaving in the story of how psychology emerges as a separate discipline seeking to differentiate itself from philosophy, without ever quite succeeding. There are chapters on Kant and Wundt, then Husserl, Heidegger, the Gestalt psychologists, Merleau-Ponty, Sartre and Beauvoir, then James Gibson, Hubert Dreyfus, and a final chapter giving a brief overview of the current state of play in embodied and enactive cognitive science. I will quickly go over a couple of the important ideas from the Merleau-Ponty chapter, then I’ll get into K&C’s discussion of what, in their view, are the most interesting current issues in the field.

Merleau-Ponty and the lived body

A hand holding the handle of a coffee cup

Can you really be sure that that coffee cup has a backside? (Source)

Husserl spends a lot of time fretting about this kind of question: How can it be that, when we look at a tree, we seem to experience the tree as having a backside, even though, right now, we can only see the front? Husserl’s solution is to posit that the tree that we experience is a mental entity, an intentional object: we see the tree as whole because we’re not directly experiencing the tree itself, we’re experiencing a copy of the tree that’s internal to our consciousness. Husserl sees this as a methodological move that allows him to ignore the question of whether the tree really does have a backside or not, or, for that matter, whether there’s any tree there at all.

Merleau-Ponty provides a different way out of the problem. He distinguishes between the lived body, which he also calls the habit body, and the objective body, or the body as an object. He uses this distinction to explain what’s going on in phantom limb cases where people who have lost a limb report still feeling pain or sensation at the location where the limb used to be. The way we normally experience the world, Merleau-Ponty says, is as a lived body that exhibits skills and habits. In phantom limb cases, the skills and habits have formed in the presence of the limb, and these skills and habits remain intact even though the objective limb itself is no longer present. The loss of the limb means that the habit body is no longer in harmony with the objective body. Now when the individual encounters a situation which used to involve the limb, the situation may still be perceived as one in which the old action is possible, but the objective body no longer supports this action.

To return to Husserl’s problem, Merleau-Ponty points out that when we encounter an object from a particular aspect, we do not do so as disembodied observers, but precisely as lived bodies. This allows us to say that when we encounter a tree, or a coffee cup, we experience these objects as having a backside to the extent that our bodies are disposed to act on the whole object. We see a tree that we can walk around, or a cup that we can wrap our fingers around. The backside is not in our perception, but in the complete act of engaging with the world.

Incidentally, this also provides the solution to a problem Chemero raised in his previous book (though K&C do not acknowledge this): how do we perceive that a beer can contains drinkable beer, if we are not representing the contents? Chemero (2009, 118) uses this example to motivate the claim that perception must be grounded in constraints and conventions. It is held that the label on the beer can is conventionally related to the presence of beer. We, as perceivers, have access both to the convention and to the label, and together these indicate the presence of beer inside the can. But Merleau-Ponty’s account of the lived body renders unnecessary any such appeal to conventions. We don’t need to perceive the beer itself, any more than we need to perceive the back of the coffee cup. Our bodily skills mean that we can just act in the presence of the beer can. And sure, it might turn out, after all, that the beer can contains sour milk, or that the coffee cup doesn’t actually have a backside. But such considerations do not normally enter into our activities. We do not live in a world where we have had to interact with milk-containing beer cans or backside-less coffee cups, so there’s no reason why our habit body would come to be shaped by such eventualities. In general, we get along just fine.

Now onto the current problems in the field. First: affordances.

Affordances, invitations, and the frame problem in ecological psychology

Affordances, it is generally said, are opportunities to act on the environment. But that raises a question: how is it that only some affordances come to be selected for action? It would seem to be the case that a detached observer is required to do the selecting—some mental controller that sits inside the organism and is able to assess the available options. This is a problem that Gibson was aware of, as shown in this passage that K&C quote twice (Gibson, 1979, 225): ‘The rules that govern behavior are not like laws enforced by an authority or decisions made by a commander; behavior is regular without being regulated. The question is how this can be.’ (Another way to put this is to say that the ecological approach provides a theory of the structure available to perception, but not a theory of behaviour as such; see this post for discussion.)

The way K&C present this is as a version of the frame problem—a problem in AI research that gave rise to much philosophical bellyaching in the 1980s, most notably from Dan Dennett. The problem is this: how can a robot ever be expected to choose its next action, given the infinite number of facts that the robot could, in principle, take into account before making its selection? As K&C see it, the only way out of this problem is to appeal to dynamical systems. An actor is a dynamical system. And the actor is nested inside a larger dynamical system—its environment. If the actor is a dynamical system then it does not need to mentally entertain any of the possible actions available to it; rather, it just acts, and it learns by changing over time. Engaging with the world not only changes the world, it also changes the internal dynamics of the actor. The outcomes of actions can have the effect of reconfiguring the attractor states within the actor’s nervous system. Here K&C appeal to Walter Freeman’s work on the neural dynamics of the rabbit olfactory bulb. If the rabbit experiences a particular scent and subsequently gets food, then this will have the effect of subtly re-configuring the rabbit’s nervous system, which will affect how the rabbit responds to the same scent the next time it encounters it (207). The frame problem dissolves because now everything is dynamic. (But I’ll have more to say about the frame problem below.)

In order to fix how we talk about affordances, K&C recommend that we follow Withagen et al (2012) in making a distinction between mere affordances and invitations. Affordances are the possibilities to act, which are always infinite in number; invitations (a term borrowed from Merleau-Ponty) are the subset of affordances that stand out at a given moment as live options. Withagen et al make this distinction in the context of a discussion of agency. K&C use it to appeal again to dynamical systems. K&C discuss the example of someone engaged in the activity of building a bookcase. The bookcase builder does not attend to an infinite world of possibilities, but only to aspects of her environment that are relevant for her ongoing project. The dynamics of this organism–environment system (builder plus bookcase-parts plus tools and so forth) have become self-organized into ‘a temporary, special-purpose dynamical system’ (203), one in which only certain affordances actually invite behaviour.

The future of phenomenological cognitive science

This is all well and good as a description of what it’s like to be a living being engaged in activities in the world. But where does it get us? How can we turn the insights of phenomenologists into a productive programme of empirical research?

How K&C propose to do this rests, in large part, on a phrase that they borrow from Shaun Gallagher and Dan Zahavi (2008), who say that, in their empirical studies of behaviour, researchers should front-load phenomenology. Unfortunately, it is not very clear exactly what work this phrase is supposed to be doing. K&C define front-loading phenomenology as ‘designing scientific experiments specifically in order to test posits concerning phenomenology’ (218). This suggests that phenomenology itself should be the subject matter of the research. But this seems at odds with what Gallagher and Zahavi themselves say (2008, 38; emphasis added): ‘The idea is to front-load phenomenological insights into the design of experiments, that is, to allow the insights developed in phenomenological analyses to inform the way experiments are set up.’ Here, it seems that phenomenology is not the subject matter of the research per se, but is part of the experimental methodology: thinking in terms of phenomenology is just part of the experimenter’s toolkit for setting up useful experiments. In their own recommendations for conducting future research, K&C seem to vacillate between two different types of strategy, neither of which seems to exactly match what Gallagher and Zahavi are after.

Strategy 1: Directly investigate stuff that phenomenologists have actually said. An example of research using this strategy is Chemero’s work with Dobri Dotov (Dotov et al, 2010), on how equipment can go from being ready-to-hand to being unready-to-hand. In the experiment, subjects are asked to play a computer game in which they have to move a mouse cursor about on a screen. At some point in the game, the experimenter interrupts the link between the mouse movement and the cursor movement. This is like what happens when you get a bit of water on your laptop trackpad, or in the old days when you got a bit of fluff taffled up in the mouse’s rollerball. As we know from having experienced this kind of thing, the disruption is apt to put us off what we had just been doing and may well cause us to flail about in an attempt to regain control of the situation. Dotov et al present this in explicitly Heideggerian terms, as a disruption that shatters our smooth coping with equipment in the environment. And they have a way of quantifying this: the disruption goes along with a disruption of the subject’s movement dynamics, which move from exhibiting pink noise (or 1/f noise, which is assumed to be characteristic of smooth coping) towards exhibiting white noise (characteristic of random movement, or flailing about). This is neat as a ‘demonstration’ of an idea from Heidegger’s phenomenology. But it is not clear how this is supposed to serve as a model for doing cognitive science in general. Are we to restrict our empirical efforts to attempting to prove Heidegger correct?

Strategy 2: Reduce everything to maths, but do so in a way that you hope is consistent with phenomenological theorizing. The second strategy is to subsume everything under the logic of dynamical systems modelling. This is defended on the grounds that complex systems are inclined to ‘self-organize and so have a tendency to behave like much simpler systems,’ and therefore ‘one will often be able to model these systems in terms of extremely simple functions, with only a few easily observable parameters’ (200). And the logic of these systems means that, in principle, it’s possible to study any phenomenon, from the level of the cell to the level of whole societies, all in terms of relatively simple dynamical equations. One might object that by reducing everything to maths, you have taken yourself outside of the realm of phenomenology altogether. Equations don’t have feelings. And there’s nothing that it’s like to be an equals sign. More to the point, there’s nothing that it’s like to be a cell or a basketball team either. Experience only operates at the level of individual organisms. By collapsing everything into mathematics, have we not lost sight of the very thing—lived experience—that caused us to so admire the phenomenologists in the first place? Surely we’re owed at least a hint of an explanation as to why it’s desirable to model experience-involving processes in exactly the same way as non-experience-involving ones. But according to K&C, there is no problem here: it’s perfectly possible to do dynamical systems modelling and still be in the business of successfully front-loading your phenomenology (201). What’s important is that the way you choose what phenomenon you are going to model in the first place should be informed by a suitably phenomenological worldview.

I have to say, I think K&C give a fair account of the current state of play within phenomenologically-informed cognitive science (that is, in enactivst and dynamical systems research). Still, neither of these two strategies strikes me as being particularly attractive.

The second strategy, in particular, seems to be too much in awe of the frame problem. I suspect that part of the motivation for trying to reduce everything to dynamical systems explanations is the worry that unless everything is expressed in the same language (mathematics) then we will never exorcise the creeping spectre of dualism and we’ll be forever stuck with some version of the frame problem. But there’s a reason why the frame problem originated where it did—in the field of artificial intelligence research. The old project in AI had the goal of building a robot with the capacity to act autonomously in a natural environment. In order to achieve that, AI researchers were going to have to be able to build a robot that could select its actions from a seemingly infinite set of possibilities. But why should we non-AI researchers take that as a model for our own psychological programme? I just don’t buy that building a working model of a behaving, living system is a realistic goal for psychology. Or a useful one. I’m much more interested in using psychology as a set of tools for intervening in real-world problems: how can we design cities that are better adapted to how we want to live, or educational resources that are better suited to how we learn, or clinical environments that better draw out the capacities of people we currently deem to be mentally ill? As such, I just don’t care about the frame problem. And neither should you!

What I’d like to see developed more is a strategy more closely aligned to that definition from Gallagher and Zahavi: to front-load phenomenology is to use phenomenology as a tool for designing experiments that can actually inform us about how we engage in specific activities—a tool that will allow us to pursue genuinely useful research. This is what Andrew was getting at in this post on dynamical mechanistic explanations. And I’ve argued (Baggs, 2014) that the appropriate way to conduct research is to take a task-oriented approach; that is, we can identify an activity that is of interest to us, from the perspective of outside analysts, but to do so we must identify a dynamic that is meaningful from the perspective of the actor. Taking this kind of approach allows researchers to study phenomena—such as steering a car round a corner, or learning to walk—that are phenomenological through and through. (See Wilson and Golonka, 2013, which sets out the general strategy for actually employing the task-oriented methodology.) The task-oriented approach seems much more worthy of the label ‘phenomenological’ than does the reduce-everything-to-maths approach.

But this is an argument for the future. For now, I’ll say that I very much enjoyed reading K&C’s book. What the book does well is it places current research in embodied and enactive cognitive science in a long-ish historical context. In doing so, the authors reveal that, far from being ‘radical’, in the sense of being outlandish and hopelessly outside the mainstream, these approaches are grounded in a solid phenomenological tradition. We inheret from Heidegger and from Merleau-Ponty a view of action as skilled engagement with the world, by a lived body. Indeed, taking this long view, it is the cognitivist AI programme that turns out to be the historical aberration. Hubert Dreyfus drily explains this in an excellent interview from 2005 (K&C also quote a different passage from this interview):

The people in the AI lab, with their “mental representations,” had taken over Descartes and Hume and Kant, who said concepts were rules, and so forth. And far from teaching us how we should think about the mind, AI researchers had taken over what we had just recently learned in philosophy was the wrong way to do it. The irony is that the year that AI (artificial intelligence) was named by John McCarthy was the very year that Wittgenstein’s Philosophical Investigations came out against mental representations. [Dreyfus may be a little muddled on the dates here—EB] (Heidegger had already done so in 1927 with Being and Time.) So, the AI researchers had inherited a lemon. They had taken over this loser philosophy! If they had known philosophy, they could’ve predicted, like me, that it was a hopeless research program, but they took Cartesian philosophy and turned it into a research program. Anybody who knew enough philosophy could’ve predicted it was going to fail. But nobody else paid any attention. That’s why I got this prize.

K&C have shown us the direction to take if we are to avoid falling back into loser philosophy. They have done us a service.

Further reading/listening

  • There’s a great Brain Science Podcast interview with Tony Chemero talking about the book, to be found here.


Is ecological psychology compatible with enactivism? Is information always animal-relative? A comment on Van Dijk, Withagen, and Bongers (2015)

One question I have had for a while is why it is that there seems to be so little overlap between ecological psychology and enactivism. Both approaches are explicitly anti-representational, both seek to treat the organism and its environment as constituting a system, and both draw their inspiration and metaphors from biology and ecology rather than, as is the case with cognitivism, from the fields of computer science and logic. And yet believers in the enactivist approach seem to have trouble communicating their ideas to believers in the ecological approach (among whom I count myself), and vice versa. It’s like there are two separate churches and the congregation inside each simply cannot comprehend the experience that led others to join the rival church.

So I was interested to read this paper by my fellow ecological psychologists Ludger Van Dijk, Rob Withagen, and Raoul Bongers (2015) who attempt to reach out to the enactivists and allay some of their concerns about the ecological approach. (Disclosure: I’ve had the pleasure to spend some time chatting with Ludger at a couple of conferences and have found we are generally in agreement on the deep issues in the field. I had nothing to do with the creation of this paper.) The paper has gone some way to clearing up for me just what the enactivists’ objection is to the Gibsonian programme. But it also raises a new issue. The authors ask ecological psychologists to abandon the concept of information about the environment in favour purely of talking about information for affordances.

I am sympathetic to this proposal. However, I do not have a very clear idea about how it will be received by the rest of the field. I am curious to find out. I suspect Van Dijk et al have understated just how much of a challenge this is to ecological psychology as it is currently practiced. I will lay out Van Dijk et al’s argument here in an attempt to set out as clearly as possible just what the dilemma is that ecological psychologists are faced with.

A content-free conception of information?

Enactivists have long worried that the ecological programme does not go far enough in rejecting the traditional dualisms of psychology, specifically the dualism that asserts that content or meaning exists externally to the animal and independently of the activity of that animal. As Van Dijk et al explain:

[Ecological psychologists] typically talk of information a lot, and it is not always clear whether this information is of a content-less kind. Indeed, the enactivist tradition seems worried about this. Varela et al. (1991), for example, felt that Gibsonians were building their “theory of perception entirely from the side of the environment” (Varela et al., 1991, p. 204). They worried that the ecological notion of information that grounded information in the correspondence between the structure of ambient light and the environment, required too little active participation of the animal.

In short, Varela et al accuse Gibsonians of merely appearing to talk the anti-representational talk while smuggling in content by the back door. They read Gibson’s description of what’s-out-there-to-be-perceived (his ecological optics) as focusing only on how light comes to contain structure from the surrounding world without explaining how the animal makes use of that structure. This leaves an explanatory gap between the structure in light and the biological and phenomenological processes internal to the animal. Or, put another way, Varela et al suspect us Gibsonians of being closet dualists, because for all our talk of the animal in its environment as a perceiving-acting system, we do not go far enough in recognizing that perceiving and acting are in fact one and the same process. Simply “picking up” information that already exists in the array is not acting; it is registering or representing. It is a passive process. Only if the target of perceiving (the objects and surfaces and so on) and the act of perceiving are truly flattened into the same process can we remove any whiff of mind-body dualism.

The solution that Van Dijk et al propose is to abandon all talk of information as being “about” something in the environment. Information-about implies that meaning exists externally to the animal and that it exists prior to the animal’s trying to act on the environment. It implies a notion of information that “carries content” from the objects in an animal’s environment to the animal’s sense receptors, to be passively detected. Instead, we should think of information as content-less: before the animal tries to act, there is no “information”, as such. Information arises in the animal’s acting on and exploring of its surroundings. The information that arises is information-for affordances; that is, it reveals to the animal possibilities for subsequent action:

“Information for” calls attention to the fact that ecological information need not be about anything – has no “aboutness” – prior to use, but it is for something to an active animal. It is for perceiving the environment, for acting on affordances and the likes.

As I stated above, I’m sympathetic to this proposal. But what Van Dijk et al do not really talk about (although they allude to it) is just how at odds this proposal is with the way information is generally talked about by ecological psychologists today.

Can ecological psychology make do without information-about?

Van Dijk et al argue that in his later work Gibson was moving away from talk of information-about in favour of purely talking about information-for. Abandoning information-about should, then, be no big deal. Except that there’s a problem: whatever direction Gibson himself might have been moving in, his followers did not necessarily continue to move in that direction. Indeed, the acceptance of both information-for and information-about is core to modern ecological psychology. Michaels and Carello make this point quite explicitly (1981, p. 37):

A description of the relation between the environment and the structure of light and sound provides one facet of the concept of information—that is, *information-about*. These patterns of energy describe objects, places, and events in the environment. However, there is a second and equally important facet of information that information-about does not touch upon. This second facet of information is *information-for* and the object of the preposition *for* is the animal. Information is the bridge between an animal and its environment and cannot be usefully described without a specification of *both*.

And, strikingly (Michaels and Carello, 1981, p. 38):

To summarize, a failure to consider both parts of information—information *about* an environment *for* an animal—is to miss the very essence of the concept of information.

In the formulation of ecological psychology that followed Gibson, then, information was explicitly defined as having two parts, and this two-part nature was seen as a feature of the concept of information, not a bug. This dual property is formalized in the symmetry principle which was put forward by Turvey, Shaw, and Mace, and which is discussed here by Andrew. The symmetry principle is presented as an account of how it is that perception can be direct. The environment is said to specify patterns in light (information) which in turn specify what is perceived. Conversely, what is perceived is said to specify what the pattern is that is in the light which in turn specifies what is in the environment (hence “symmetry”). According to this formulation, it is not a problem if light is said to carry information about the environment. On the contrary, this is seen as a good thing because it explains how it is that we perceive what is actually in our environment. “Information” is merely the central term in a set of 1:1 correspondences that point in two directions at the same time: to the environment and to the perceiver. (But note that while the symmetry principle makes reference to perception it does not make reference to the activity of the animal, which lends support to the enactivists’ suspicion that perception is being covertly treated as the passive inputting of content.)

Other formulations of information by ecological psychologists also rely on information-about. Both Chemero (2009, p. 116 and following pages) and Wilson and Golonka (2013) attempt to develop a version of information that draws on Barwise and Perry’s situation semantics. Here, the symmetry principle is abandoned and it is allowed that information can be “about” something that is not directly specified in the pattern in the energy array. So a spoken sentence can be said to be about something more than just the sound pattern and the vocal equipment that produced that pattern: it can be said to be about what the sentence is in fact about. Instead of appealing only to specification, these authors appeal to constraints that have to be learned, and that link the pattern to its meaning. But, crucially, the pattern is still said to have a meaning, independently of the activity of the actor. This is what Van Dijk et al are asking us to give up: the idea that meaning exists independently of the animal and its actions.

The dilemma for Gibsonians

A confession: not so long ago I used to think of enactivism as merely a form of old-fashioned idealism masquerading as modern biologically-inspired scientific psychology. Enactivism is easy to dismiss because the book that’s presented as foundational to the field, Varela et al’s (1991) The Embodied Mind, is also a self-indulgent foray into Buddhist scholarship. I used to think that the only reason that enactivists weren’t Gibsonians was because they simply hadn’t appreciated the enormity of Gibson’s achievement. Now I am not so sure. I am now persuaded that at least some of the problems that enactivists see are real, and that those problems are not merely an artefact of how the ideas have been communicated to outsiders but are internal to the ecological approach. Van Dijk et al’s paper has helped crystallize that for me. It is not enough to just insist that we are right; we need to do more work if we wish to persuade others that that is the case. So it will be useful to try to be clear about just what the challenge is that we are faced with.

Part of the problem may be that Gibson’s approach to perception is in large part really a theory of structure. Ecological optics is about the correspondence between structure in light and the structure of the world. It provides an account of what’s out there to be perceived, but not of how we learn to make use of that structure, still less of how our use of that structure comes to shape the things we can do when we’re no longer looking at the structure directly (e.g. how it is that I can remember scoffing at Varela et al’s arguments even though I no longer have their book in front of me). It’s been pointed out that the way James J. Gibson and Eleanor J. Gibson divided up their study interests—the former focusing on the senses while the latter focussed on perceptual learning—has introduced a long-standing divide into the entire field. If we really want to persuade the enactivists that Gibson is worth following then we are going to have to take on the hard work of putting the active learner back into its environment. Van Dijk et al argue that this requires a concept of information that is truly animal-relative and content-free. (They also argue that James J. Gibson was himself engaged in pursuing this conception as he attempted to develop his theory of affordances.)

The dilemma appears to be thus:

  • We can concede that much of ecological psychology is not really a theory of psychology but a theory of structure, a theory of what’s-out-there-for-an-animal-to-perceive; this need not be seen as a defeat: we can insist that Gibson’s account is the best account of structure that we have and that no anti-representational approach to psychology can succeed that doesn’t acknowledge Gibson’s great achievement here
  • Or we can insist that Gibson’s approach really does constitute a theory of psychology, and we can continue to conduct empirical research in the traditional ecological manner: taking some arbitrary task (such as stair-climbing or aperture-passing) and attempting to identify the invariant that is implicated in the control of that task; this option has worked well up to now and it has certainly been productive; but this approach may preclude ecological psychologists from having anything much to say about phenomena that go beyond the immediate perception of structure, things like language and other social phenomena (i.e., the concerns of this blog), or indeed about any phenomenon that appears to involve creativity or spontaneity on the part of the actor

The strange thing is that Van Dijk et al wrote their paper in an attempt to ride to Gibson’s defence, against enactivist attacks. In doing so they have revealed to us just how much work we still have to do. I suppose this may seem like a rather negative conclusion but I don’t think it is. I think it’s quite exciting that some of this hard work is still there to be done. I’m curious to find out if others feel the same way.