tag:blogger.com,1999:blog-9192597712746432631.post7999968277723823407..comments2024-03-09T09:06:35.288+00:00Comments on Notes from Two Scientific Psychologists: The Affordances of Everyday ThingsAndrewhttp://www.blogger.com/profile/16732977871048876430noreply@blogger.comBlogger21125tag:blogger.com,1999:blog-9192597712746432631.post-44697236943156391622015-11-30T23:19:13.495+00:002015-11-30T23:19:13.495+00:00The pull-handle affords the shop-owner a convenien...The pull-handle affords the shop-owner a convenient manner of closing the door firmly when he goes home at night.<br /><br />Tony Nichollhttps://www.blogger.com/profile/06713110520326372567noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-11044960148800662432013-02-05T23:05:47.297+00:002013-02-05T23:05:47.297+00:00The "actions of perception" are tremendo...The "actions of perception" are tremendously understudied, given their crucial importance in Gibson's system.Eric Charleshttps://www.blogger.com/profile/17412168482569793996noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-64679511302719841702013-02-02T08:28:22.787+00:002013-02-02T08:28:22.787+00:00I agree entirely. Now, ecological psychology has n...I agree entirely. Now, ecological psychology has not been great about tackling this fact; we are a little guilty of talking carelessly about affordances. That's a fixable problem, though,Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-28827759788632407362013-02-01T21:44:20.658+00:002013-02-01T21:44:20.658+00:00It's funny how we still tend to want to frame ...It's funny how we still tend to want to frame affordances as things we're supposed to grasp based on information we get just from standing still & looking, when Gibson goes to great lengths to say we get information only through *action* within the environment. <br />As you say, you had insufficient information by just walking up to the door and seeing it visually - you had to act on the object in order to experience that the event your perceptual system expected was not going to happen. Grasping the door and pulling *is* part of your perception. That's how you get to the other layers of the nested structures in your environment, no? <br />(I realize this is an old post and this was probably settled, but I'm in the thick of it, so couldn't help but toss my thoughts in ...)Andrew Hintonhttps://www.blogger.com/profile/11201418632360464282noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-9748381628426345222011-11-19T10:34:35.149+00:002011-11-19T10:34:35.149+00:00Not all dispositions are affordances, but all affo...Not all dispositions are affordances, but all affordances are dispositions (under this scheme). So we're highlighting a set of action relevant dispositions and calling those ones affordances; standard science move. <br /><br />The effectivity is not necessarily the size and shape of the hand. As I said, body scale is just the first thing people looked at (eg Warren expressing stair riser heights as proportions of leg length). I'm inclined to agree that body scale is unlikely to contain the full effectivity; but as yet we don't have a rigorous alternative. <br /><br />Graspability is indeed the property we want to get to. But understanding how that property is composed is important, because that then determines how that affordance can be specified in, say, light, and the affordance is of no use if it produces no information. Information is the critical thing for Gibson, and it gets left out of the analysis a lot because it's hard. This is a problem.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-76277757065372723082011-11-19T03:19:29.968+00:002011-11-19T03:19:29.968+00:00@Andrew Wilson
Sorry, I got confused there. I sho...@Andrew Wilson<br /><br />Sorry, I got confused there. I should have said the effectivity would be the organism's pull. The actualisation (the effecting) would be pulling. The shape and size of the hand (among other things) would be the vehicle of the organism's pull. (This probably makes more sense with graspability. The effectivity would the organism's grasp. The vehicle of its grasp is the shape and size of the hand.)<br /><br />"This makes them dispositions."<br /><br />If I can say the effectivity is just the shape and size of the hand, then surely I can say the disposition is just the shape and size of the object, and then why do I need to speak of affordances at all? Is it just a convenience? But surely the whole point is that graspability, and not merely the shape and size of the object, is perceptible. If affordances are to be real things, then we shouldn't reduce them to their vehicles, and we shouldn't reduce effectivities to their vehicles either.scientismnoreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-71438490611714123042011-11-18T15:03:50.760+00:002011-11-18T15:03:50.760+00:00Turvey does get carried away with his words; but I...Turvey does get carried away with his words; but I think the dispositional framework has a nice discipline to it. I also don't agree that it makes anything trivial; me grasping something does mean a) the object is graspable and b) I can grasp that thing, but there are numerous empirical questions that remain (how is the affordance composed? What is the information for it? etc).Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-1396963802343536292011-11-18T13:29:09.006+00:002011-11-18T13:29:09.006+00:00@scientism
The Turvey formula is a trivial idea wr...@scientism<br />The Turvey formula is a trivial idea wrapped up in an unnecessarily sophisticated jargon. <br /><br />Turvey says: "Realization of the affordance" because "object affords", and "we have effectivity".<br /><br />Which can be read as: We behave when there is a thing that can be changed, and we have the ability to change it. <br /><br />I suppose one of the reasons I don't like Turvey's formula, which I don't think I've brought up too much on this blog, is that <i>if</i> Ecological Psychology = that formula, <i>then</i> there there would be nothing interesting or controversial about ecological psychology. That I find many people interesting, and that many more people find it highly controversial, suggests there is something more going on. Alternatively, many, many otherwise very smart people could be quite confused... which happens. <br /><br />The typical alternative proposal for Eco Psych, that affordances are the relation, and that the relation itself can be perceived, is at least a little more interesting, and more understandably controversial.Eric Charleshttps://www.blogger.com/profile/17412168482569793996noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-64342357300834272272011-11-18T06:52:03.086+00:002011-11-18T06:52:03.086+00:00In the Turvey framework, pulling the door is effec...In the Turvey framework, pulling the door is <i>effecting</i> the affordance, which you can do by virtue of your <i>effectivities</i>; these are the properties of the organism which complement the affordance and thus allow the disposition to be played out. <br /><br />Body scale was one initial swing at finding effectivities. It's had mixed success.<br /><br /><i>The shape and size of the organisms hands are not dispositions at all and therefore cannot be effectivities either. They are instead the vehicle that enables the pulling, just as the microphysical properties of salt enable it to be a solvent.</i><br />This makes them dispositions.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-20780664033915818092011-11-18T02:05:42.293+00:002011-11-18T02:05:42.293+00:00After reading through the posts on affordances, it...After reading through the posts on affordances, it seems to me that Turvey must be confused about effectivities. Surely the actualisation of the pull-ability of a door handle is its being pulled. The effectivity, therefore, is pulling and not, say, the shape and size of the organisms hands. The shape and size of the organisms hands are not dispositions at all and therefore cannot be effectivities either. They are instead the vehicle that enables the pulling, just as the microphysical properties of salt enable it to be a solvent. They are complementary with those properties of the handle that enable its pull-ability: its size, shape, rigidity, etc. The compulsory effecting problem goes away on this account since pulling is the actualisation of our ability to pull, which we can choose whether or not to exercise.scientismnoreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-66142256057326387222011-11-04T16:41:51.590+00:002011-11-04T16:41:51.590+00:00If ... I reach out to grab the door nob and open t...<i>If ... I reach out to grab the door nob and open the door ... at that moment I was ... the type of organism that was afforded door opening</i><br /><br />Perhaps the problem I see with this way of looking at it would be clearer if put into the vocabulary of intentionality.<br /><br />I see the affordances offered (actually continuous but sequenced for convenience) as something like: approachable, reach-for-able, graspable, pull-on-able, but not openable. A primitive critter (adaptive robot) might be "disposed" (designed) to execute that specific context-dependent sequence notwithstanding having no intentionality, ie, propositional attitude: wishing or desiring <b>that</b> the door be open, hoping or believing <b>that</b>something yummy is behind the door, etc. And that's where I think Ken's examples all go wrong. They mix a description of a subject's behavior in the psychological vocabulary of intentionality with a description in the ecological vocabulary of affordances. And opening a door is similar. If the closed door is understood to offer the openable affordance - initially distal, later proximal - the paradox of the subject's being unable to immediately effect a proximal "affordance" arises. But not if opening the door is viewed instead as the object of an intentional posture. By definition, an affordance can't be thwarted; a hope, wish, or desire can.<br /><br />I'm clearly shooting from the hip here, trying to integrate a bunch of ideas grasped fuzzily at best. But perhaps there's a kernel that someone better positioned than I can do something with. Eg, I can kind of see this fitting into Andrew's robot post (representational robots pursuing intentions, dynamical systems robots pursuing affordances??) but not clearly enough to suggest how.<br /><br />Obvious question: did Gibson make some analous distinction between the automaton-like behavior of a creature qua "dynamical system" and the (supposedly) "intentional" behavior of a creature qua "mindful system"?Charles T. Wolvertonhttps://www.blogger.com/profile/12309746685166449683noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-88586470633657345532011-11-04T13:29:37.625+00:002011-11-04T13:29:37.625+00:00Two quick thoughts:
Regarding dispositions - So fa...Two quick thoughts:<br />Regarding dispositions - So far as I can tell, the only way to make the dispositions argument work is to off load a lot of nuance into the notion of "effectivities". If, given many things a person of my general body type could potentially do, I reach out to grab the door nob and open the door, ipso facto, at that moment I was, at a much more detailed level of analysis, the type of organism that was afforded door opening... and nothing else. This line of thinking makes me feel worried for lots of reasons, but it works. I don't think this is what Gibson was saying, but it is a potential foundation for ecological psychology. I just wish that Turvey et al were willing to own the implications more strongly so that a better conversation could be had. <br /><br />Regarding the two minds problems: This is a very long standing problem in philosophy. For example, William James and his students... the ones who would influence the future behaviorists and ecological psychologists... were very concerned with it 100 years ago. If you are a realist, the problem is entirely "scientific" and not at all "philosophical" as the terms are usually understood. However, if you are stuck trying to make a case for realism, some philosophers will still think it is kind of a big deal.Eric Charleshttps://www.blogger.com/profile/17412168482569793996noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-61365127538044721392011-11-03T15:05:20.939+00:002011-11-03T15:05:20.939+00:00I should note that it isn't just "some su...I should note that it isn't just "some support". Not, of course, terribly "scientific", but FWIW the key Davidson paper arguing this - "3 Varieties of Knowledge" yields 266K google hits. The much more famous Quine's "Two Dogmas" and Sellars' "Empiricism and Phil of Mind" get 330K and 376K respectively. So, at least by that measure, "3 Varieties" is in roughly the same league.<br /><br />So, I'd say your hunch was pretty good!Charles T. Wolvertonhttps://www.blogger.com/profile/12309746685166449683noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-13843302552466220882011-11-02T07:36:35.369+00:002011-11-02T07:36:35.369+00:00Needless to say, I'm happy to think that I'...<i>Needless to say, I'm happy to think that I'm finally nore-or-less on board the eco-psyche train! And it took only a year+. Once again, your patience is appreciated.</i><br />Woohoo! I always thought we should get sent chocolates when we talk someone into being ecological :)<br /><br /><i>Thus, if Chemero really says "I am not currently trying to effect all the affordances in my vicinity", either he is wrong (there is only one and it must be effected) or he is not assuming that affordances must be immediately effected. </i><br />Mostly the latter. He presents the fact that there are multiple affordances available and that we aren't trying to effect them all as evidence that they aren't dispositions. I think your time scale issue gets to the heart of that, though.<br /><br />Point 2: the subtlety is that Tony is concerned that we don't know enough to characterise the complementary effectivity precisely. He has a point about body scale not cutting it, but I tend to think this is a state-of-the-art problem more than something we can never solve, because, as you say, the complement is in the system somewhere, it's just up to us to find it.<br /><br />Overlapping minds: you've described it correctly. Chemero's read Heft and noticed that you need relations to solve the problem, but he didn't read Heft close enough to realise that <a href="http://psychsciencenotes.blogspot.com/2010/06/reading-group-problem-of-two-minds-heft.html" rel="nofollow">the relation is the act of perception, not the thing perceived</a>. <br /><br />Also I tend to agree it's a feature, not a bug, for the reasons you suggest, although that's only ever been a hunch. Nice to know there's some support :)Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-84746165768141197052011-11-01T19:19:59.580+00:002011-11-01T19:19:59.580+00:00Needless to say, I'm happy to think that I'...Needless to say, I'm happy to think that I'm finally nore-or-less on board the eco-psyche train! And it took only a year+. Once again, your patience is appreciated.<br /><br />Assuming that in your post on "Chemero Chap 7: Affordances" the initial three point summary of Chemero's objections to affordances as dispositions is reasonably accurate, I see these problems:<br /><br />Point 1 - If affordances must be immediately effected, there clearly can be only one at any specific time. Thus, if Chemero really says "I am not currently trying to effect all the affordances in my vicinity", either he is wrong (there is only one and it must be effected) or he is not assuming that affordances must be immediately effected. As for dispositions, I agree with Chemero that they are context dependent, but also agree with you that the context can (generally will) be complex and time-varying. <br /><br />What I take to be the mistake - which many of us make, but as a determinist I have no excuse for making - is to assume that at any time there is a choice to be made among affordances/dispositions. Again, I think it's a matter of time scale. Over any finite time interval T, there may be many actions that conceivably could have been taken during T if one considers only those aspects of context that were constant throughout T: the size of the door handle relative to the subject's hand, the subject's strength, et al. But at a specific instant, the context includes a multitude of elements that are time-varying over T. I submit that considering the total context at any instant, there is only one possible move, viz, to effect the one affordance/disposition that everything that has happened up to that instant has resulted in being offered to the subject - or in your preferred vocabulary, the move that all information available at that instant dictates. (Using the analogy of a continuous-time system, at the beginning of T the system could conceivably follow any of multiple paths. At any instant, however, it's immediate future (on the scale of the delta-t of calculus) presumably is determined by the input up to that instant (assuming "typical systems", eg, no "quantum-weird" stuff going on).<br /><br />Point 2 - From the perspective of the above discussion of Point 1, the complement of a disposition/affordance is present by definition since an affordance/disposition must be immediately effected. Ie, no effectivity, no affordance/disposition. But perhaps I'm missing some subtlety.<br /><br />Point 3 - I really don't get the "overlapping minds" bit. I skimmed through some of the various cited papers but gave up when I encountered what seemed to be an argument based on Berkley-style idealism - seemingly quite irrelevant to the issue at hand. <br /><br />I gather that the envisioned problem is, in short, that if two minds perceive (in some sense) the same object, they have (with respect to that object) the same mental content, which would violate some aspect of the assumed privacy/authority/whatever of first person perspective. I certainly can't make a coherent argument refuting this, but Donald Davidson could, and did. In fact, contrary to minds overlapping due to similarly perceiving a common entity (object or event) being a problem, he argued that it is a requirement for communication. Here too perhaps I'm missing a subtlety, but to me this objection seems a non-starter.Charles T. Wolvertonhttps://www.blogger.com/profile/12309746685166449683noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-57594608142647192172011-11-01T10:50:01.300+00:002011-11-01T10:50:01.300+00:00Actually, this made me think of something. Your de...Actually, this made me think of something. Your description, which is basically right, is what Tony was trying to achieve with his <a href="http://psychsciencenotes.blogspot.com/2011/04/chemero-2009-chapter-7-affordances-etc.html" rel="nofollow">Affordances 2.0</a>. I still think that information is the solution to the problems Tony was raising; <i>information</i> ebbs and flows, affordances don't. So I'm on board with the need for their to be dynamic, time-varying access to affordances, I just don't think affordances themselves have to be relations to achieve this.<br /><br />Just a connection I wanted to make explicit.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-66086384511925637272011-10-31T18:22:37.400+00:002011-10-31T18:22:37.400+00:00That all seems about right to me.That all seems about right to me.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-24122773036724256072011-10-31T16:01:05.704+00:002011-10-31T16:01:05.704+00:00"Ken's problem is he can't work time ..."Ken's problem is he can't work time into his thinking."<br /><br />I think he works time in but on the wrong scale. The counterexamples I recall all involve viewing a distant scene and judging that some element of that scene offers an affordance. But that seems to confuse a long-term goal and an affordance, the latter - but not the former - offering immediate actualizability. If one thinks of the problem as being to assess the behavior of a continuous time adaptive system with feedback, the time interval of interest is the small delta t of calculus, not the large delta T of advanced planning. So, I think eric is right to identify the affordance as "pull-on-able", an immediately and continuously actualizable affordance over some finite time interval. <br /><br />Viewing it like that also solves the problem I've had with persistence. If one interprets a goal (here, opening the door) as an affordance, the problem of actor-dependence arises: as eric notes, that "affordance" is offered to the terminator (or whatever character he has in mind - I don't know Arnold's movies) but not to us wimps. But pull-on-able is offered to any critter that can effect graspable. And Andrew's continuous flow of information, manifest in the resistance experienced while effecting that affordance, will be different for Arnold from what it is for us, resulting in our ultimate continuing behavior diverging from Arnold's since he will be offered new affordances different from those offered us.Charles T. Wolvertonhttps://www.blogger.com/profile/12309746685166449683noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-54957315225530163702011-10-31T06:57:11.996+00:002011-10-31T06:57:11.996+00:00In the case of the door, I correctly perceived tha...In the case of the door, I correctly perceived that the door handle afforded grasping and pulling, and did not perceive (because there was no information) that this would not work. Like friction, there was no information about the underlying properties available ahead of time; only when I pulled on the door did information become available,and then I acted accordingly.<br /><br />Ken's problem is he can't work time into his thinking. You always need to ask, who knew what, and when, and on what basis? Affordances are real and persist, but the information for those affordances can swing in and out of 'view' as you move through the world. <br /><br />Charles, the fire code thing works except when I was there I had to push the door in.Andrewhttps://www.blogger.com/profile/16732977871048876430noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-32785895345967172552011-10-31T05:15:10.079+00:002011-10-31T05:15:10.079+00:00The concept of affordances can get ugly in the gre...The concept of affordances can get ugly in the grey areas, but it is beautiful in its natural habitat. I really like the examples of bad design, though they speak to the ugly grey area. <br /><br />The problem is that the doors of the McDonald's DID afford pulling-on (as evidenced by the fact that you realized the affordance). However, much to your frustration, they did not afford opening-towards-you-from-the-street.* So, does your firm tug reveal correct perception or incorrect perception? <br /><br />This is an interesting levels of analysis problem, and I'm not sure what to do about it. Often times in these discussions, when the notions of affordances gets shaky, one can seemingly find solid ground by shifting the scale of the behavior and outcome. However, shifting scales is typically a cheating move, because it typically changes the subject of the conversation rather than answering the question. (Typically, but not always.)<br /><br />I've tried to wrestle with this before and never found a satisfactory solution. <br /><br /><br />-----<br />*To be even more generous, the doors might well have afforded opening-outward-by-pulling-the-handle... just not to someone of your strength level. I'm envisioning a robotic Arnold Schwarzenegger taking the door against its hinges and casually walking in as if nothing unusual had happened. Even were this true, the question still remains: If you were mistaken about your ability to enact a specific type of change on the environment, does that prove a PERCEPTUAL error has occurred, or could the perceptual part of the story still have been error free?Eric Charleshttps://www.blogger.com/profile/17412168482569793996noreply@blogger.comtag:blogger.com,1999:blog-9192597712746432631.post-18317844516187280942011-10-31T04:02:27.683+00:002011-10-31T04:02:27.683+00:00I think fire safety codes typically require exteri...I think fire safety codes typically require exterior doors of certain establishments to open outward, and it appears from the photo that the once offending doors did so at the time of the photo. This together with the fact that only one door was openable at the time of your earlier (?) visit suggests the possibility of a temporary malfunction rather than a design flaw. <br /><br />In any event, the unopenable door seems to be yet another example of Ken's unactualizable (non-?)affordances.Charles T. Wolvertonhttps://www.blogger.com/profile/12309746685166449683noreply@blogger.com