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Article 5890 of comp.ai.philosophy:
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>From: erwin@trwacs.fp.trw.com (Harry Erwin)
Newsgroups: comp.ai.philosophy
Subject: Re: Grounding: Real vs. Virtual (formerly "on meaning")
Keywords: symbol, analog, Turing Test, robotics
Message-ID: <604@trwacs.fp.trw.com>
Date: 25 May 92 14:46:53 GMT
References: <595@trwacs.fp.trw.com> <1992May22.152511.675@news.media.mit.edu> <ppyky7j.nagle@netcom.com> <1992May23.141738.14114@news.media.mit.edu>
Organization: TRW Systems Division, Fairfax VA
Lines: 42

minsky@media.mit.edu (Marvin Minsky) writes:

>In "Society of Mind" I made a weak argument that humans have evolved
>to be especially helpless in infancy -- so that they're forced to
>learn more from their parents.

Actually this argument can be strengthened if you note that not being
helpless at birth has a number of costs:

1. It forces the mother to carry the fetus for a longer period, thus
placing more strain on her immune system, reducing the number of infants
produced in a lifetime, and increasing her vulnerability to predation. The
extended gestation period seen in placentals is a late adaptation,
requiring a sophisticated placenta. The marsupials instead have a system
based on an internally-retained egg, with birth occuring only when the
maternal immune system begins to react to the fetus.

2. It forces physical adaptions in both the infant and the mother. In our
species, this has resulted in a female pelvis that is less efficient than
it otherwise would need to be and in a significantly increased risk of
losing the mother during pregnancy.

3. It forces the brain to develop the motor cortex prior to birth. (Even
in man the motor cortex is relatively advanced at birth.) This makes that
portion of the brain vulnerable to reduced oxygen during the birth process
and means that the neuronal connections must be relatively "hard-wired" in
the genome. This latter increases the resources required to maintain the
genome _or_ reduces the amount of genetic code available for other
purposes.

>From the standpoint of fitness, deferring the development of any organ
system is probably preferred, and when it is energetically as expensive as
the brain, all the more so. You can probably find some good studies of
this issue in the biological literature,



Cheers,
-- 
Harry Erwin
Internet: erwin@trwacs.fp.trw.com



