Tuesday, 19 April 2011

Chemero (2009) - A Brief Pause to See Where I'm At

There are still a couple of chapters left for me to go over in Chemero, but the last two were the crux of the book for me, and I want to try and summarise where my analysis has left me before I go on holiday for Easter.

First, I'd like to separate out a couple of themes. First, there's the overall 'radical embodied cognitive science' programme, and second is the specific form of the 'shored up ecological psychology' that Chemero advocates as a basis for this programme. I am entirely on board with the basic idea of RECS; specifically, I think that cognition, whatever that is, is non-representational and that we can make great progress by making our science non-representational. I think Chemero has written a clear exposition of what such a radical science might look like, and why we might want to bother, and I think this makes RECS a must read for the field. 

Second, I think that Chemero is right to go to ecological psychology for a theoretical basis. The more I look, the more I have come to believe that James Gibson is about the only psychologist to have actually proposed a genuine scientific theory in psychology. A true theory provides you with tools to empirically attack novel problems in your domain, and provides you with a clear basis to interpret the results of your tests and to begin to tell a coherent story. Psychology has been chasing phenomena for most of it's scientific life, with no clear framework emerging to tell us a story about why things are the way they are. Ecological psychology is a genuine theory, and it's about a critical feature of our psychological lives: how we maintain contact with our world and move through it successfully. Regardless of what topic you're specifically interested in, you need to understand how we come to have knowledge about our environments.

Finally, though, I have problems with the proposals Chemero makes about the two pillars of an ecological psychology, affordances and information. It's these problems I want to try and sum up here, to focus the conversation a little.

Wednesday, 6 April 2011

Chemero (2009) Chapter 7: Affordances, etc (Pt 2)

Last time I went over affordances-as-dispositions, and Chemero's first swing at affordances-as-relations. Affordances can't be dispositions, claims Chemero, because
  1. Dispositions manifest when the conditions are met; this is compulsory. But I am not currently trying to effect all the affordances in my vicinity, so they can't be dispositions. Relations are functions, and thus support malfunctions.
  2. Dispositions require complements - for perception-action, the complement of an affordance is an effectivity. But what exactly is this? Body scale (e.g. leg length)? Actually, it's more likely in terms of ability (per some unpublished experiments Chemero has run); people's judgements of stair climbability are a relation between the riser height and the person's ability to step that high.
  3. If affordances are properties that are directly perceived, then when two people perceive the same affordance their minds will overlap: the problem of two minds. Relations solve this problem by making the overall relation which the directly perceived affordance is part of unique to each observer.
This would be all well and good, except that 
  1. Affordances and effectivities are complex dispositions, and the conditions for being realised can be a long list. In addition, I can only be one kind of effecting device at a time, so when seated I am literally not capable of complementing the climbing affordances of my stairs at that moment in time.
  2. Noting that 'body scale' is an imperfect proxy for an effectivity, and then claiming that this means nothing is an effectivity makes no sense. In addition, 'abilities' are equally approximate. The issue (being careful what you claim is the actual complement of the affordance) is valid but applies equally to dispositions or relations.
  3. The solution to the problem of two minds that Heft outlined and Chemero thinks supports his case lies in making the act of perception relational, not the thing perceived. The affordance does not, itself, need to be a relation.
So far, nothing has convinced me that affordances need to be relational. But to round the story out, I want to finish the chapter and address the final tweak Chemero adds: Affordances 2.0.

Tuesday, 29 March 2011

Chemero (2009) Chapter 7: Affordances, etc (Pt 1)

If you want perception to be direct (no 'mental gymnastics') you must identify where the content of perceptual experience comes from; when I view a chair, for example, I don't see a meaningless or random collection of surfaces or colours, I see an object that I can interact with in some ways and not others. For traditional, indirect theories of perception, this meaning is constructed internally: mental representations perform transformations (perhaps computational ones) on sensory input to infer what the input means. A theory of direct perception requires that meaning is not added to the signal; this 'enrichment' is not permitted. To solve this problem, Gibson proposed that the world, for a perceiving-acting organism, is not comprised of meaningless bits of physics and chemistry. Instead, he proposed that the world presents itself to this organism in terms of affordances, which are intrinsically meaningful for the organism and are about the possibility of behaviour.

So a theory of direct perception requires an ontology, a theory about the make-up of the world  that means it is intrinsically meaningful. Chemero wants RECS to include direct perception, therefore he needs such an ontology. He is happy with affordances; he is not, however, satisfied with the Turvey-Shaw-Mace approach which defines affordances as dispositions. This chapter will defend an extended version of his theory of affordances as relations: Affordances 2.0.

Affordances have cropped up here, er, a couple of times already - namely here, here, here, and most recently and enthusiastically here, as well as some empirical discussions here and here. The idea that affordances, not physics, is the correct ontology for a theory of direct perception also came up here. To jump ahead, I disagree with Chemero about affordances. I don't think the disposition account is flawed in the way he thinks, and I don't think relations solve the problem anyway. While I obviously agree that an affordance-based ontology is the way to go, I am so far satisfied that the dispositional account is the best current analysis, and I think that trying to make affordances relational is to confuse the world with information about the world.

I'm going to take this chapter in two parts, because this post got long; affordances are complicated things. After this chapter, I think a pause for station identification may also be in order, just to lay a few things out in response to Chapters 6 and 7, the real meat of the book. But first, Affordances 1.0 vs Affordances 1.1.

Tuesday, 22 March 2011

Chemero (2009) Chapter 6: Information and Direct Perception

In the previous chapter, Chemero laid out his first idea as to how a radical embodied cognitive science could be a science; he suggested taking a 'dynamical stance' in which researchers use simple dynamical systems models such as the HKB to drive empirical work. In this chapter, he moves towards his more recent suggestion, namely using Gibson's ecological psychology as a theoretical basis from which to make predictions and run experiments. This is a much more robust idea; sciences need theories or else they wander from phenomenon to phenomenon, which I believe to be a real issue in modern psychology and cognitive science.

Chemero has his own flavour of ecological psychology, however. He believes it stays true to Gibson's essential framework but expands it to cope with new and important issues. The two pillars of ecological psychology, information and affordances, remain. Chapter 6 is Chemero's expanded notion of information, while Chapter 7 is his updated theory of affordances as relations (which I've covered briefly before).

Tuesday, 15 March 2011

Chemero (2009), Chapter 5: Guides to Discovery

The dynamical stance laid out by Chemero in the previous chapter has a potential flaw (besides being a bit weak-ass) - it's not clear how it can serve as a guide to discovery. How do you do productive science taking this approach? Chemero is going to make two suggestions, only one of which I think works: first, he's going to suggest dynamical models such as the Haken-Kelso-Bunz (HKB) model can serve to stimulate empirical work even when they are entirely phenomenological. This approach is, I think, entirely incorrect, and this chapter is full of serious problems (only some of which are unique to Chemero). Second, he's going to suggest that Gibsonian ecological psychology can actually solve the problem much more robustly anyway, by serving as an underlying theory of behaviour. This will work better, and I would advocate Bingham's model of coordination as an exemplar of this, more promising route.

But first, the HKB model as guide to discovery (this chapter is largely the material from Chemero, 2000; I intend to turn this post into a paper to rebut that paper and point to the Bingham model as an alternative, so comments are especially welcome on this one). Time to get a little critical, I'm afraid.

Tuesday, 8 March 2011

Chemero (2009), Chapter 4: The Dynamical Stance

The problem with the theory of representation Chemero settles on in the previous chapter, as we shall see, is that it makes representation unavoidable. If there are representations, then RECS fails to get off the ground (remember, the radical bit is anti-representationalism). In this chapter, Chemero identifies a path past this problem (the 'dynamical stance'), explains why it works, but then concludes with a new problem, that of how to guide future discovery.

Tuesday, 1 March 2011

Chemero (2009), Chapter 3: Theories of Representation

The radical part of 'radical embodied cognitive science' is anti-representationalism. Simply put, the claim is that the brain does not internally represent states of the world in any way, nor are these the basis for our experience. It's radical because to a typical cognitive scientist, the mere suggestion is ludicrous: like suggesting you do biology without genes or particle physics without Large Hadron Colliders. But this indignation is hiding a dirty little secret: mental representations are generally just assumed to exist, because of assumptions about the poverty of stimulus we supposedly face. They are theoretical entities designed to solve a problem which, frankly, might not exist. There has been a lot of theoretical work on what it means to be a representation, but most of this has occurred in philosophy and most modern experimental cognitive psychologists don't ever engage with the issue. Sabrina has talked about this a bit already here and here and here and it's likely to keep cropping up.

Chemero's third chapter lays out some basics about what a theory of representation has to look like. If you're going to be anti-representational you need something to be against that isn't a straw man. This is unfortunately difficult because the concept of representation is a moving target: if I had a dollar for every conversation I've had that included the phrase 'Oh, that's not what I mean by representation' (even when it really is), I wouldn't need to submit the grant I should be working on just now. This chapter is therefore going to look for a 'minimal case' of representation that doesn't bug too many people but that isn't too easy a target.

Strap in, this chapter's busy.