Wednesday, August 11, 2010

Discrimination on the Basis of Underlying Causal Processes

Menary quotes us on this:
Adams and Aizawa stipulate that "the cognitive must be discriminated on the basis of underlying causal processes" (Adams and Aizawa 2001, p. 52). 
But, I think this misrepresents what we do.  I don't think we stipulate anything.  We point out that other sciences have worked this way, so we might plausibly assume that cognitive science will go this way.  Here's the broader context (perhaps a little too much):
The second necessary condition is a condition on the nature of processing. This point bears much more elaboration than did the preceding. The old saw is that science tries to carve nature at its joints. Part of what this means is that, to a first approximation, science tries to get beneath observable phenomena to find the real causal processes underlying them; science tries to partition the phenomenal world into causally homogeneous states and processes. Thus, as sciences develop a greater understanding of reality, they develop better partitions of the phenomenological. A range of examples will point out what we are driving at.
     In the Novum Organum, Francis Bacon proposed a set of methods for determining the causes of things. According to one of these methods, to find the cause of X, one should list all the positive instances of things that are X, then find what is common to them all. As an example, Bacon applies this method to the “form of heat.” On his list of hot things, Bacon includes the rays of the sun, fiery meteors, burning thunderbolts, eruptions of flame from the cavities of mountains, all bodies rubbed violently, piles of damp hay, quicklime sprinkled with water, horse-dung, the internal portions of animals, strong vinegar which when placed on the skin produces a sensation of burning, and keen and intense cold that produces a sensation of burning. Bacon conjectured that what was common to these was a high degree of molecular vibration and that the intensity of heat of a thing is the intensity of molecular vibration. Bacon clearly intended to carve nature at its joints, but it simply turns out as a matter of contingent empirical fact that the things that appear hot, or produce the sensation of being hot, do not constitute a natural kind. The rays of the sun, meteors, friction due to heat, body heat, and so forth, simply do not have a common cause. There is no single scientific theory that encompasses them all; the phenomena are explained by distinct theories. Friction falls to physics. Decomposition
falls to biology. Exothermic reactions to chemistry.
     As a second example, there are the late 19th century developments in the theory of evolution. By this time, Darwin’s biogeographical, morphological, taxonomic, and embryological arguments had carried the day for evolution and many biologists had come to accept the theory of evolution by common descent. Despite this, the majority of biologists were reluctant to accept Darwin’s hypothesis that evolution is caused primarily by natural selection. In this intellectual environment, biologists returned for a second look at Lamarckian theories of the inheritance of acquired characteristics. In support of their theory, neo-Lamarckians pointed to cases which, in retrospect, proved to be instances in which a mother would contract some disease, then pass this disease on to her offspring in utero. Phenomenologically, this looks like the inheritance of acquired characteristics, but, in truth, inheritance and infection
involve distinct causal processes. Inheritance involves genetic material in sex cells of a parent being passed on to offspring; infection is the transmission of an alien organism, perhaps via the circulatory system in isolation from the sex cells. To a first approximation, inheritance is a process in the germ line of an organism, where infection is a process in the soma line of an organism. It is only after the true causal differences between inheritance and infection are made out that one can conclude that we have one less instance of the inheritance of acquired characteristics than we might at one time have thought. Throughout the episode, Lamarckians were aiming to carve nature at its joints, but in the absence of a true understanding of the nature of the processes underlying inheritance and infection, these distinct processes had to appear to be the same, both as instances of the inheritance of acquired characteristics.
     The cognitive may, therefore, be assumed to be like other natural domains, namely, the cognitive must be discriminated on the basis of underlying causal processes. The point we have been driving at here might be approached in another way, namely, we believe there is more to cognition than merely passing the Turing test. Some of the mechanisms that might be used to pass the Turing test will count as cognitive mechanisms for doing this, while other mechanisms that might suffice will not count as cognitive mechanisms. A computer program might pass the Turing test by having a listing of all possible sensible conversations stored in memory. Such a program, however, would not   constitute a cognitive mechanism for passing the test. This is presumably because we have sufficient ground for saying that the look-up table process is not of a kind with the complex of processes that go into enabling a normal human to carry out the same sort of conversation. The look-up table may, for example, answer questions in a constant amount of time for each sentence. Computer chess provides another famous sort of case where behavior can be carried out by both a cognitive and a non-cognitive process. In chess, there is a combinatorial explosion in the number of possible moves, responses, counter responses, and so forth. As a result, it quickly proves to be impractical to examine all the logically possible moves and countermoves. The most powerful chess playing programs, therefore, use special techniques to minimize the number of possible moves and countermoves they have to consider. Nevertheless, there is pretty strong reason to believe that the chess-playing methods currently employed by digital computers are not the chess-playing methods that are employed by human brains. Based on observations of the eye movements of grandmasters during play, it appears that grandmasters actually mentally work through an extraordinarily limited set of possible moves and countermoves, far fewer than the millions or billions considered by the most powerful chess-playing computer programs. The point is not simply that the computer processes and the human processes are different; it is that, when examined in detail, the differences are so great that they can be seen not to form a cognitive kind. The processes that take place in current digital chess playing computers are not of a kind with human chess playing.  (Adams & Aizawa, 2001, pp. 51-52, italics added for emphasis).
I think this is a pretty important idea.  I think that rejecting it in favor of things like "cognitive behavior" leads to all kinds of bad consequences for, for example, Rupert and, sometimes, Clark.

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