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OK, excellent; since you assert that PCT has so much more predictive power, I'm sure you can show me many impressive, quantitative PCT-driven experimental results that aren't in a domain (like motor response or game strategy) where I already expect to see control-system-like behavior.
For example, if you could get a mean squared error of 10% in predicting a response that balances ethical impulses against selfish ones (say, the amount that a person is willing to donate to a charity, given some sort of priming stimuli), then I'd consider that good evidence. That's the sort of result that would get me to pick up a PCT textbook.
Seriously, please point me to these results.
You've just crossed over two different definitions of "predictive" -- not to mention two different definitions of "science". What I described was something that would give you a "hard", strictly falsifiable fact: is the person controlling variable X or not?
That's actual science. But what you've asked for instead is precisely the sort of probabilistic mush that is being critiqued here in the first place. You are saying, "yes, it's all very well that science can be used to determine the actual facts, but I want some probabilities! Give me some uncertainty, dammit!"
And as a result, you seem to be under the mistaken impression that PCT has some sort of evidence deficiency I need to fix, when it's actually psychology that has a modeling deficiency that needs fixing. How about you show me a genuinely reductionistic (as opposed to merely descriptive) model of human psychology that's been proposed since Skinner?
I only mentioned PCT in this thread in the context of Yvain's request for an example of people making the mistake Richard wrote this post about. And you responded to my criticism of psychology (i.e., it's not a "hard" science) by raising criticisms of PCT that are in fact off-topic to the discussion at hand.
Are you claiming that, if PCT is flawed, then everything in psychology is just jim-dandy fine? Because that's a pretty ludicrous position. Check your logic, and address the topic actually at hand: the complete failure of cognitive-level psychology to come up with a halfway decent reduction of human behavior, instead of just cataloging examples of it.
Otherwise, you are in the exact same position as an intelligent-design advocate pretending that gaps in evolutionary biology mean you don't have to consider the gaps in your own theory, or lack thereof.
Because PCT could be ludicrously wrong, and it would still be a huge advance in the current state of psychology to be able to nail down with any precision why or how it was wrong.
Which is why critique of PCT is irrelevant to this topic: you could disprove PCT utterly, and the given criticism of psychology would still stand, just like disproving evolution wouldn't make "God did it" any more plausible or useful of a theory.
So let's say, for the sake of argument, that I utterly recant of PCT and say it's all gibberish. How would that improve the shoddy state of psychology in the slightest? What would you propose to replace PCT as an actual model of human innards?
Let's hear it. Name for us the very best that modern psychology has given us since Skinner, of any attempt to actually define an executable model of human behavior. Has anyone even tried, who wasn't an outsider to the field?
I'll give this one last try.
You've given me the two results I mentioned above, in the area of motor response. They sound like good experiments to me: you can take a model with relatively few free parameters, and find that most subjects' behavior will fit that model extremely well for some particular values of the parameters. That is the kind of experiment I'd take as good evidence that control theory operates in motor response. (Incidentally, if you could give me a link to those experiments, I'd much appreciate it.)
You've been claiming for months that this is just the tip of the iceberg, that PCT is able to isolate variables that subjects are controlling in cognitive contexts like belief. I would be very interested in this claim if I saw some evidence for it; fortunately, your claim that PCT is able to diagnose and treat cognitive conditions implies that it's strong enough to do the same kind of experiments as in the case of motor response. So I began by asking for references to such results, and gave an example of the kind of result that would definitely move me to look into PCT.
Experimental verification seems to me like the obvious thing for PCT advocates to do if they're confident in their theory and frustrated by its lack of academic respect. I would therefore find it highly unlikely, given that your claims are true, that in 35 years there hasn't been a single positive experimental result in a cognitive context, of the same form as the "controlling the position of the dot" or "varying the force on the bar" experiments. That you meet my question with outrage, rather than with citations, is thus Bayesian evidence against the validity of PCT.
Nope. I'm just claiming that if PCT doesn't have the kind of evidence it claims, then I probably shouldn't bother investigating it. The problems with mainstream psychology are manifold, but the discipline seems to be making (slow) progress by scientific criteria: Tversky and Kahneman, for instance, were making novel and unexpected experimental predictions that turned out to be correct. If your discipline does that much better than mainstream psychology, there should be some strong experimental results that show it.
I really can't imagine that's too much to ask, and that's why I've made this challenge. Point me to experimental results that validate PCT in a cognitive context, and I'll pick up the textbook of your choice. Keep grandstanding against the very kind of evidence you presented as evidence of PCT in motor response, and I'll have to conclude that you're peddling woo-woo. The ball is in your court.
I take it you skipped reading Marken's references then, since I believe one of the cited papers was on how physicians' errors in prescribing medicine match a PCT model of the situation, but fail to match an intuitive model of how such errors would respond to environmental changes.
You've apparently also been ignoring my repeated mention of time-averaged perceptual variables like "the amount of work I've done today" or "how recently I got laid" - you can have a "feel" for such values, and how they change over time, as well as respond to changes in them. Do you claim to not perceive -- and control -- such variables? Or are you going to say that since "work" and "getting laid" involve physical activity, they are somehow therefore "motor" rather than "cognitive"?
Finally, you seem to have put me in the strange position of a passing physics student being harangued by a young earth creationist, insisting that I prove the age of the universe to your satisfaction, before you will study any physics, whereas I assert that if you were to go and study some physics, it will be obvious to you why YEC-ism is wrong.
But after being harangued at some length, I relent and attempt to begin with some basic equations, which you then argue are not in the Bible and thus not valid evidence. It is at this point, I begin to question who you're trying to convince by your diatribe, and why, if you genuinely want to learn something, why you're spending more time writing than reading. Don't you have a library anywhere near you?
I'm not sure I follow you here, since I've only referred to neuroanatomy evidence -- i.e. evidence from a "hard" science. You may be confusing me with one of the other PCTers here who've been talking about the joystick perception experiments, which I consider only relevant for debunking Skinner... which isn't really as useful as it used to be.
OK, that does sound like a result of the type I'm looking for. I think I can find "Error in skilled performance" at my campus library. In the meantime, could you tell me if the following are true in your opinion:
Thanks.
I would guess Marken is respected; I have not read the paper, only his brief mention of the results in a talk he gave summarizing his 25 years of PCT-related research. I have no idea whether you would consider it "strong evidence". However, here is a portion of that synopsis:
OK. Well, I've read the paper now, and I find that I strongly disagree with a key component of Marken's methodology, and that I think this zeroes in on the cause of our argument here about what kind of experimental evidence counts for PCT. Frankly, though, I don't want to spend time arguing against it only for you to say "OK, maybe Marken is a crank, but that doesn't say anything against other PCT researchers". So if it's not too much trouble, could I ask you to read the (short) paper and tell me:
If the answer to either of these questions is "No", then we're just back where we started, with me asking for experimental evidence for PCT in a cognitive context. If the answer to both is "Yes", then I think I can explain my disagreement.
Thanks for your efforts at an even-handed attempt at seeing if PCT meets vital reality checks.
If Marken will turn out to be both a crank and a respected member of PCT community, it will say something about the community.
ETA: Technical report "Error in Skilled Performance: A Control Model of Prescription Writing" (2002) can be found online here.
If it's not too much trouble, would you mind answering even ONE of the many, many points and questions I've brought up in this thread? I mean, as long as we're not trusting each other, I frankly don't trust you not to change your criteria on the fly, either.
For example, you've still not defined what your criteria for what you'd consider a "novel" result, nor which "standard model" you would use as a baseline for comparison. Nor have you addressed the issue of any of the many cognitive variables that are available for your direct observation, nor what your criteria are for what you'd deem "cognitive" vs. "motor".
These are all areas where you are quite free to change your stance at will, and I do not wish to waste any more of my time, if your true goal here is simply to find an excuse (at any cost) to not learn something. I want to make sure that you've stated your true objection first.
Fair enough.
It's hard to define explicitly what I'd consider a novel or surprising result, because— as you point out— mainstream psychology doesn't appear to have a unified reductionistic model of cognition, just an array of identified results and sub-models. I've thus made that requirement more charitable, changing it from "something novel or surprising" to the lower standard of "good modeling by control theory of a cognitive phenomenon", excluding motor response and some games (like a fielder catching a fly ball) in which acting externally like a simple control system is an easy and successful strategy.
By "motor response" I mean just the way that the actual nerves and muscles can vary their particular actions, while not changing the conscious description of what I'm doing. For example, I assign significant probability that a simple control circuit can be found that neatly fits the actions of my leg muscles (or the nerve signals that connect to them) when I'm walking and keeping my balance. I would, however, find it much less probable that a similarly simple control circuit fits my pattern of working vs. procrastinating. (Since control circuits are apparently Turing-complete, of course there's going to be some control circuit that matches it, but in the case of balance I think there's probably one with few enough parameters that it compresses the data effectively, compared to other models; while in the case of akrasia I doubt this.)
So I would count work vs. procrastination, or prescription errors, or charitable donations, or changing beliefs, as just a few examples of cognitive phenomena. Something like variation in libido over time, though, wouldn't surprise me as much if I find a control circuit model for it (though it would surprise me more than the balance example). I think it's fair to ask PCT for experimental evidence in the cognitive domain, since the way you diagnose and prescribe around here seems to presuppose some rather simple control circuits in cognitive phenomena.
As for considering direct introspection rather than experimental evidence, I'm rather mistrustful of what I consciously intuit about my own mind, since conscious awareness seems to be often distorted for signaling purposes, and since the false perception of religious experience (which I really wanted to be genuine) was one thing that kept me religious longer than I should have been. At this point, I strongly prefer experimental evidence.
With that said, could you read Marken's paper and tell me whether you stand behind it in the terms I asked above?
Now that I've read it, I have to say I agree with you: it is not good evidence. At best, it's an application of PCT to generate an interesting hypothesis or two.
I'm not sure why you'd expect akrasia to be a simple circuit. If it were a simple conflict, between exactly two things, you'd likely be able to resolve it consciously without much effort. A few weeks ago, I did a workshop where we charted a portion of one person's control structure in the area of not working on the iPhone app they wanted to write. It took a couple hours and filled most of a page with the relevant cognitive-level variables and their interconnections.
This is quite consistent with e.g. Ainslie's model of akrasia as involving multiple competing "interests"; I see PCT as an improvement over Ainslie in providing a straightforward implementation mapping, plus simplified management of Ainslie's notion of "appetites", which is not very well worked out (IMO) and a little too handwavy.
Replacing Ainslie's idea of "interests" having "appetites" with controllers measuring time-averaged variables seems like a straightforward win: instead of two entities, you have just one entity that's structurally similar to things we know our brains/nervous systems already have. (Also, Ainslie has no worked-out model for how prioritization and agreement between interests occur; PCT on the other hand has hierarchy and reference levels to account for them.)
Individually, the circuits are simple; collectively, the networks are not. I used to think things were simpler than they are, because I focused only on the things (functional beliefs) that were effectively connections between control circuits. I rarely addressed the settings of the circuits themselves, or used them as a springboard to identifying other beliefs or variables.
There's a difference between having a false label applied to a true experience, and having a false experience. The existence of perceptions such as "how much work I've gotten done lately" or "how much fun I'm having" is certainly some evidence for PCT's notion of time-averaged perceptual variables that can influence decision-making. It's also parsimonious to assume that the brain is unlikely to have evolved specific circuits for these perceptions, rather than simply having a basis for acquiring new perceptions.
In effect, the PCT model of cognitive variables explains how we represent all the things we "just know" or "just feel", including expert intuition in specialized subjects. The PCT prediction would be that if someone is skilled enough in a subject to have a specific intuition about something, we should be able to find a specific neural signal whose intensity corresponds to the degree of that intuition, and which is a time-averaged function of other (possibly gated) input signals.
I don't see how any of this seems extraordinary or controversial in the slightest, on the perception side.
Control, perhaps, might be more controversial... especially given the implication that we don't control our own actions directly, but can only do so through interaction with the control network. But for me, that implication is uncontroversial, because I've been writing about that (independently formed) idea since 2005.
Powers hypothesizes that "awareness" simply is a debugger that can go in and inspect any part of the network, injecting settings or testing hypotheticals. Anything we do by direct conscious intention would therefore consist of "manually" setting control values in the network, which of course would have no long-term effect if a higher-level controller puts the settings right back when you're done. What's more, if your conscious meddling is interfering with something in an "important" (high) position in the network, it's likely to reorganize in such a way that you no longer want to meddle with the network in that particular way!
And that actually sounds like the most straightforward explanation of akrasic behaviors, ever, and is also 100% consistent with everything I've already previously observed about mind hacking.
That is, we really don't control our own behaviors: our networks do. Free will is really just a special case, even if it doesn't seem that way at first glance. PCT just offers a better explanation than my rough models had for why/how that works.
Sorry, but that doesn't sound like an interesting result that vindicates PCT. You can even rephrase the general insight without controls terminology!
Like this: "given a system that is demonstrably robust against failure mode X, it's unlikely to fail in mode X".
Positing a "control system" is just unnecessary length and unnecessary delimitation of the general rule. PCT doesn't get you this insight any faster. And while human factors engineers would discourage similarly named, very different drugs, even they would admit it might not be worth fixing if the system has already operated without ever swapping out the drugs.