Tuesday, November 9, 2010

A second reason for thinking smart mechanisms likely?

For at least two reasons the likelihood of smart mechanisms in perception should be considerable. ...
The second reason has to do with the principle that when designing something one does not normally make it more complex than necessary. The perceptual mechanisms were not designed by a human mind, however, and are therefore not subordinate to the same complexity scale(s) as man-made devices. Biological evolution might have arrived quite easily at solutions which require the utmost of capacity and sophistication of a human mind for their basic principles of operation to be understood. (Runeson, 1977, p. 174).
This second line of reasoning seems simplistic to me.  Grant that when humans design things they often try to make them no more complex than necessary.  But, humans often design things starting from a "clean slate".  By contrast, when natural selection designs things it must begin with "what its got".  So, when natural selection began to design bipedal walkers, it had to begin with a spine that was originally designed for quadrupedal locomotion.  That means that there can end up being an ultimate design that is suboptimal.  By parity of reasoning, for all we know, natural selection faces certain design constraints when it begins to develop visual systems using things like light-sensitive cells.  It seems to me that it is our ignorance of possible design constraints that makes this kind of evolutionary speculation fraught with risk.  This is why this does not seem all that convincing to me.

And I am willing to grant the possibility of what biological evolution might have done, but recall that at this point Runeson is supposed to be arguing about what biological evolution has likely done, or at least why "the likelihood of smart mechanisms in perception should be considerable."  (I'm assuming that "considerable" means something like high, but I guess it could mean non-negligible.  Kind of unclear really, if you ask me.)

Runeson, S. (1977).  "On the Possibility of 'Smart' Mechanisms" Scandinavian Journal of Psychology, 18, 172-9.


  1. Smart solutions are robust but niche specific. they don't solve a wide class of problems generally, they solve a narrow class of problems specifically. Sounds pretty evolutionary to me :)

    Perception is the process by which we maintain contact with the world - that's serious business. The pressure to access the best available visual information shouldn't be underestimated. Errors, misperceptions, etc all have real consequences; miss that branch and fall out of the tree, or fail to detect the lion and you get eaten.

    And in Runeson's defence: the paper is called 'On the possibility of 'smart' mechanisms'.

  2. And, I was thinking that this post might be unnecessary since what I wrote in the last one (and its comments) basically says everything I say here ...

    "Sounds pretty evolutionary to me :)"

    Yeah, that's what worries me! =)

    "And in Runeson's defence: the paper is called 'On the possibility of 'smart' mechanisms'."

    Yeah, I picked up on that, which is why I drew attention to the fact that at this point in his paper he is arguing for the likelihood.

  3. I'm as suspicious as you are of what passes for evolutionary stories in psychology. Evolutionary psychology is an embarrassment to the field. But I meant what I said here; solving a niche specific problem with niche specific resources is precisely the kind of thing evolution does.

    So yes, point taken. I think Runeson's on slightly stronger ground here because the information driving the evolutionary story is still around, unlike a lot of the pressures evol. psych make up to explain things, so we know it really could have served as pressure. But you're right, it's a story you have tell carefully.

  4. "solving a niche specific problem with niche specific resources is precisely the kind of thing evolution does."

    Well, if FAPs and the shark case are supposed to be illustrations/examples of these smart mechanisms (I'm not sure, since as I've said I'm not sure what Runeson's "targets" or "exemplars" are supposed to be), but I don't see how humans have many (if any) FAPs or niche specific solutions as do sharks. But, maybe this stuff works better for the fly-ball catching stuff than it does for vision.

  5. Our hands are pretty niche specific. Quite useful, but highly specialised.

  6. See my comment in the other thread ...