About the blockquotes in this comment, for some reason I can't separate your quotes from the paper's quotes if they're right after one another, so you'll have to pay attention. To be clear, my response will always follow your quote. I've looked at Markdown syntax documentation but I can't figure out how to fix this. I'd appreciate help from anyone.
CFAR exist in the background of the realisation that's quite easy to want to be rational and read a list of mental biases but that this usually doesn't make people more rational. It thus important to develop techniques to reliably make people more rational and that includes us as well.
I know what CFAR is and what it's for, I just said that because I didn't know if they had tried rationality training with anyone else but entrepreneurs and people with a lot of experience in mathematics. If this has changed, I'd appreciate it if someone told me.
Just because someone changes their beliefs doesn't mean they do Bayesian inference. Bayesian inference is a specific heuristic and I consider it unlikely that the body uses it for this purpose.
For one, I didn't say that Bayesian inference was the conscious process by which the person changed their beliefs.
Now, I'll begin by saying that I don't know an explicit thing about Bayesian inference. Despite that, I wrote that because I've seen this researcher cited elsewhere on the site and I assumed that if he used the adjective 'Bayesian' in one his papers, you all would want to know about it. From the paper, these are the things that I'm talking about:
Wheras Botvinick & Cohen (1998) interpret their results in terms of resolving incongruities between visual versus proprioceptive location of the hand, our table experiment would lead us to argue that the illusion arises mainly from the ‘Bayesian logic’ of all perception; the brain’s remarkable ability to detect statistical correlations in sensory inputs in constructing useful perceptual representations of the world—including one’s body.
We suggest that the principle underlying this illusion is Bayesian perceptual learning—that two perceptions from different modalities are ‘bound’ when they co-occur with a high probability.
The McGurk effect is much easier to demostrate if you want to show someone how is perception is flawed.
I had never heard of this, but I just read the introduction to the Wikipedia article to get an idea of it and apparently the McGurk effect is hit or miss. To my knowledge, everyone can experience the rubber hand illusion regardless of previous experience.
As for this:
I'm not really sure that the paper demostrates that. You could also say that the person has empathy with the table.
I really don't believe that one could say that. I may be wrong, but it seems that the paper actually addresses this:
The brain’s remarkable capacity for extracting statistical correlations in sensory input is most apparent in the table condition. In the hand experiments, given the visual similarity between the fake and real hand, it is not unreasonable for the brain to tolerate some level of discrepancy between the felt position of the hand and its apparent visual location. (Indeed, Graziano (1999) has shown specific cells in the macaque to be responsive to the visual appearance of both a monkey’s real hand and a proximate fake one.) This argument, however, is difficult to apply to the case of the table; indeed, we would argue that the assimilation of the table into the body image is dictated exclusively by the Bayesian logic underlying all perception; in this case the brain’s tendency to take advantage of statistical correlations (even when they do not ‘make sense’ from the cognitive point of view and contradict a lifetime of experience with our own bodies).
Mimikry of body language leads in humans to a feeling of rapport.
I don't understand how this is relevant.
I'm also uncomfortable with the semantics of "human body" in this case. I would guess that most of the participants wouldn't say that the table is part of their body.
I agree that it's improbable that a person would explicitly consider the table a part of their body. I also think that it's probably true that most of the participants wouldn't say that they can anticipate or feel pain due to injury to something that is not part of their body.
I've looked at Markdown syntax documentation but I can't figure out how to fix this.
Separate paragraph by empty lines.
[re mimikry] I don't understand how this is relevant.
They get the effect by having a stimulus applied at the same time to both hands. If the real hand moves the fake hand moves as well in the same way. That's how you create rapport. If two people are in strong rapport and you hurt one of them, the other also feels hurt.
...I also think that it's probably true that most of the participants wouldn't say that they can anticipate or fee
It seems that the CFAR workshops so far have been dedicated to people who have preconceptions pretty close in ideaspace to the sorts of ideas proposed on LW and by the institutions related to it. This is not a criticism; it's easier to start out this way: as has been said, in a different context and perhaps not in so many words, we should focus on precision before tractability. We're not going to learn a thing about the effectiveness of rationality training from people who won't even listen to what we have to say. Nevertheless, there will come a day when these efforts must be expanded to people who don't already view us as high in social status, so we still have to solve the problem of people being more concerned with both our and their social status than with listening to what we have to say. I propose that the solution is to divorce the consideration of social status from the argument.
There is a lot of talk of cognitive biases on LW, and for good reason, but ultimately what we are trying to teach people is that they are prone to misinterpreting reality, and cognitive biases are only one component of this. One of the problems with trying to teach people about biases is that people feel personally responsible for being biased; many people have a conception of thinking as an 'active' process, so they feel as though it reflects upon their character. On the other hand, many people conceive of perception as a 'passive' process; no one feels personally responsible for what they perceive. So, I propose that we circumvent this fear of character assassination by demonstrating how people can misinterpret reality through perception. Enter: the rubber hand illusion.
In case you're unfamiliar with this illusion, to demonstrate the rubber hand illusion, a subject sits at a table, a rubber hand is placed in front of them, oriented relative to their body as a natural hand would be, and a partition is placed between the rubber hand and their 'real' hand such that they are unable to see the 'real' hand. Then, the experimenter simultaneously 'stimulates' both hands at random intervals (usually by stroking each hand with a paintbrush). Then, the experimenter overextends the tips of a finger on each hand, the rubber hand about 90 degrees, and the 'real' hand about 20 degrees (it's not really overextension, and it wouldn't cause pain outside of the experiment's conditions). Measurements of skin conductance response indicate that subjects anticipate pain when this is done, and a very small selection of subjects even report actually experiencing pain. Also, (just for kicks) when subjects are questioned about the degree to which they believe their 'real' finger was bent, they overestimate, by an average of about 20 degrees.
As Dr. Vilayanur Ramachandran has demonstrated, the rubber hand illusion isn't the most general example of this sort of illusion: the human mind can even anticipate pain from injury to the surface of a table. In fact, there is evidence that the human mind's evaluation of what is and is not part of its body isn't even dependent upon distance: Dr. Ramachandran has also demonstrated this with rubber hands attached to unnaturally long rubber arms.
I think that there are also three beneficial side effects to this exercise. (1) We are trying to convince people that Bayesian inference is a useful way to form beliefs, and this illusion demonstrates that every human mind already unconsciously uses Bayesian inference all of the time (namely, to infer what is and isn't its body). To further demonstrate the part about Bayesian inference, I would suggest that subjects also subsequently be shown how the illusion does not occur when the rubber hand is perpendicular to the 'real' hand or when the 'stimulations' aren't simultaneous. (2) After the fact, the demonstration grants social status to the demonstrator in the eyes of the subject: "This person showed me something that I consider extremely significant and that I didn't know about, therefore, they must be important." (3) Inconsistencies in perception instill feelings of self-doubt and incredulity, which makes it easier to change one's mind.
Addendum: This post has been substantially edited, both for brevity and on the basis of mistakes mentioned in the comments, such that some of the comments now appear nonsensical. Here is a draft that I found on my desktop which as far as I can tell is identical to the original post: http://pastebin.com/BL81VQVp