Showing posts with label Fodor. Show all posts
Showing posts with label Fodor. Show all posts

Friday, January 14, 2011

Fodor on Thinking in English/Pictures

From a book review in which Fodor spends a lot of time challenging argument for the view that we do not think in English, Menary takes the following:
 “I wouldn’t be in the least surprised, for example, if it turned out that some arithmetic thinking is carried out by executing previously memorised algorithms that are defined over public language symbols for numbers (“now carry the ‘2’ and so forth”).” (Fodor 1998, p. 72)
This looks bad for A&A, but the context matters.  So, here is more of Fodor's book review:
I want to end by returning to a point I've already made in passing. I don't think that there are decisive arguments for the theory that all thought is in Mentalese. In fact, I don't think it's even true, in any detail, that all thought is in Mentalese. I wouldn't be in the least surprised, for example, if it turned out that some arithmetic thinking is carried out by executing previously memorized algorithms that are defined over public language symbols for numbers ("Now carry the '2,'" and so forth). It's quite likely that Mentalese co-opts bits of natural language in all sorts of ways; quite likely the story about how it does so will be very complicated indeed by the time that the psychologists get finished telling it.
     But here's a bet that I'm prepared to make: For all our philosophical purposes (e.g., for purposes of understanding what thought content is, and what concept possession is, and so forth), nothing essential is lost if you assume that all thought is in Mentalese. Hilary Putnam once remarked that if you reject the analytic/synthetic distinction, you'll be right about everything except whether there is an analytic/synthetic distinction. Likewise, I imagine, in the present case: If you suppose that all thought is in Mentalese, you'll be right about everything except whether all thought is in Mentalese. More than that is maybe more than it's reasonable to ask for. (Fodor, 1998, p. 72).
Now, this is a kind of puzzling concession on Fodor's part, but he seems to be willing to make it only because he thinks nothing philosophically interesting turns on it (and because the evidence is less than decisive).  And, if I thought that I might agree.  But, something philosophically interesting does seem to me to turn on this, so I don't agree.

So, I want some empirical evidence that we do arithmetic in English or in pictures.  Fodor notes the inadequacy of the taking literally the familiar claim that we think in English.  This seems to me to be all that Menary has.

As for Dehaene, I'm not holding my breath for decisive evidence.  The issue has been around for a while without resolution to the satisfaction of all.

Thursday, November 11, 2010

Runeson on Perceptual Tools

In analogy with the planimeter and its user, our perceptual systems will be considered as a set of smart instruments which are (more or less actively) used by our intellect to get information about the environment.
     The study of perception would then be the study of the perceptual instruments. This may be subdivided into the search for the principles behind the function of the instruments, and the discovery of the physical realizations of these principles, i.e. how these instruments are actually built. The former would be the psychological part of the enterprise and the latter would be the physiological part.
     The relation between perception and cognition is modelled by the relation between the planimeter and its user. However, it is only the non-perceptual
functions of the user which are relevant to the model. Thus, our model does not contain a complete homunculus--only a cognitive, emotional, etc., homunculus. This should be a proper procedure when the focus of interest is on perception.

Sensory psychophysics
The study of relations between simple physical variables and experience is based on the implicit or explicit assumption that such relations are fundamental for the apprehension of "secondary" properties like causality and depth. Even when one finds the latter properties more interesting, one feels obliged to study the "primary" ones first. Mostly, such studies indicate that we are very bad at judging simple variables. This seems paradoxical when confronted with the delicate perceptual tasks we repeatedly perform in normal life.

I find the tool plus user story striking for its similarity to Fodor's later hypothesis of modules plus central system.  This parallelism then invites the comparison between Runeson's tools and Fodor's modules.  Right away, the principal difference appears to be that Fodor's tools begin with simple transductions, then performs computations to yield outputs that are "useful" to the organism.  So, the vision module will provide something like an accounting of the 3D layout of objects in the world.  It would be a rote mechanism, I assume.  By contrast, Runeson tools will (likely) be ones that provide direct pick up of things like the 3D layout of objects in the world.  These would be "smart" mechanisms.

If we think about Fodor's account of modules, Runeson's "paradox" goes away.  What the visual module does is take physical stimuli plus "assumptions" to generate hypotheses about the 3D layout of objects in the world.  It is because of the nature of module output that we are not so good at describing the inputs.  The modules don't simply regurgitate the inputs; they give us, instead, things like the 3D layout of objects in the world.

Note as well that Fodor's modules can respect some version of the Gibsonian idea that vision is not for detecting points, lines, etc.; instead it is for perceiving "meaningful" things in the environment.  It's just that Fodor's module yields the meaningful by indirect perception.

And, indeed, this seems to me to be a common way for tools to operate.  Often tools measure things we do not care about in order to give us information about things we do care about.  So, in fMRI, we do not really care about changes in blood oxygenation levels, we care about changes in brain activity and changes in blood oxygenation levels (at least putatively) just gives us part of the means to infer brain activity.  IR spectroscopy gives us a measure of the absorption of infrared light at different frequencies.  We don't really care about that absorption spectrum; instead we care about what it enables us to tell about the chemical structure of the tested compound.