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Evolution will select for brains with more accurate models subject to other constraints and as a result, I doubt it will rarely (if ever) reach a global maximum
by mattkrause 7y ago
Evolution will select for brains with more accurate models subject to other constraints and as a result, I doubt it will rarely (if ever) reach a global maximum.
More accurate models presumably have costs (e.g., bigger brains are metabolically expensive). The fitness landscape has local maxima, and they may be hard to move away from (as in the eyes I mentioned above). There are lots of caveats like those.
We know that a lot of internal models are not particularly accurate. The visual system only acquires a tiny bit of high-resolution data at time (with a hole in it[0]) and interpolates the rest. Loss aversion, the gamblers' fallacy, and the rest suggest we're not great at modelling uncertain outcomes. Even mental models of physics differ from reality in some key ways [1].
It's possible that these are still slowly improving, but I think it's more likely that much better models have an unfavorable cost-benenfit profile.
[0] The blind spot is different from the nose. There's a whole in your representation of the world, a few degrees away from the center of gaze. Your brain fills it in in surprising ways. Here's a fun demo that's a big hit with kids too: http://people.whitman.edu/~herbrawt/classes/110/blindspotdemo.pdf http://people.whitman.edu/~herbrawt/classes/110/blindspotdem...
[1] Josh Tanenbaum's group has some cool studies looking at people's mental models of physics, which you may find interesting: https://www.pnas.org/content/110/45/18327.short https://www.pnas.org/content/110/45/18327.short