Wesley R. Elsberry
Posts: 4991 Joined: May 2002
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Quote (Missing Shade of Blue @ Dec. 20 2008,05:14) | Wesley,
I'm not claiming our inductive biases are perfect, especially when it comes to highly theoretical predicates like "phlogiston" or "caloric".
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What, heat transfer is more complex than the chemistry of color perception and cognition?
I don't think so.
But at least we have an agreement that the "none have come to pass" claim was false.
Quote | But our folk inductive assumptions about medium-sized dry goods (stuff like shape, sensory properties, causal properties, etc.) works well enough to allow us (and all kinds of other animals) to get by pretty well. And that in itself is surprising to me.
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So far, you haven't managed to communicate that surprise in a way that would make it contagious. For those of us with some grounding in the history of science, cognition, and zoology, the claim that perceptual systems represent "inductive biases" requiring supernatural tuning for their effectiveness does not look at all attractive. And I had to choke back quite a bit to make that description more neutral.
Quote | The radical Humean skeptic about induction: "Hey, why do you think nature will continue to be so stable and uniform? How do you know Planck's constant won't change tomorrow? Or that your cat won't turn into some kind of evil fire-breathing demon?" This is the kind of thing people make fun of philosophers for.
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We know, by induction, that future conditions will change. Populations here are not preparing for Sol's eventual red giant stage of stellar evolution.
Quote | Goodman's skepticism is subtly different, and to me far more troubling. It's not "Why do you think nature is, to a large extent, uniform across time?"
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But it isn't uniform across time. Paleontology tells us that.
Quote | It's "Granted that nature is uniform, what does that mean?" And the answer is that it depends on your choice of vocabulary. What it would be for nature to be uniform is different for creatures with blue-green vs. grue-bleen predilections. Now we were endowed with certain predilections in the distant past, and it turns out that so far, nature has actually been pretty uniform on our preferred descriptions. Our biases haven't been perfect, sure, but our inductive expectations are very rarely shattered by everyday macroscopic phenomena millions of years after they evolved. And that fact in itself, I suspect, puts them in a set of measure zero in the space of all possible biases.
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And 99% or more of all species that have ever lived are extinct. There's plenty of "biases" that didn't pan out over the long term. Keeping this in mind may help prevent cases of Panglossianism.
Quote | Quote | As yet unobserved conditions or stimuli (as in the "ue" of "grue") are also unavailable to natural selection; why would anybody imagine that natural selection could develop systems corresponding to "grue-bleenism" prospectively? |
It seems like the lack of clarity in my initial post has claimed another victim. I hope the response I wrote to Keith makes things a little clearer. The point I was trying to make was that "grue" and "green" are really on the same footing evolutionarily. In particular, "grue" does not involve unobserved conditions or stimuli any more than "green" does.
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Sure it does. It requires an observation that color is temporally unreliable. And then there was the other consideration about such "potential biases"...
Quote | To suppose otherwise is to assume an asymmetry between the predicates that can only be justified by our inductive bias. And it is the emergence of that very bias that we're trying to explain. Note that the temporally disjunctive aspect of grue and bleen is merely an artifact of their representation in our blue-green basis. If we try to represent blue or green in a grue-bleen basis, then they would appear temporally disjunctive. |
"Keiths" already pointed out the issue of simpler representations, a consideration that grounds "an asymmetry between the predicates" and has nothing to do with "inductive biases", making that claim of yours a false one, too. Look up the "universal distribution". This is stuff from algorithmic information theory, if that will help your search.
Something you apparently overlooked from the prior exchange:
Quote | Quote | Now what confuses me is that it seems that it is basically impossible to come up with an evolutionary explanation for this apparent design.
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Since the "apparent design" claim seems to be based on a false premise, it doesn't look like there is a problem in the offing.
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The demonstration that "inductive biases" are, in fact, imperfect leads directly to the diminution of the force of the claim that preternatural effectiveness obtains.
-------------- "You can't teach an old dogma new tricks." - Dorothy Parker
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