oded@wisdom.weizmann.ac.IL (Oded Maler) (08/29/89)
Inheritance and IQ
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Let's summarize:
1) Intelligence is a vague concept, some aspects of which can be
very roughly quantified by IQ tests.
2) Any attempt to characterize intelligence precisely and rigorously
is doomed to fail since we are dealing with multi-dimensional entity
that can be manifested in endless external and internal ways.
3) Multi-dimensinality implies no strict linear order among persons,
so it is usually meaningless to claim Int(x)>Int(y).
4) In spite of all this, let us agree that there is some notion of
intelligence that we can attribute to people in varying degrees of
"intensity".
5) Unless one is a strict dualist, it can be asumed that a person's
intelligence resides in (is implemented by) his/her physical body.
6) It is also commonly agreed that most of that intelligence resides
in the central nervous system, and determined by its structure.
7) The morphology of the human body (and the brain) is determined
partly by genetics and partly by interactions with the environment.
8) The mental capacities of a person at a given moment reflects in
some way the current structure of his/her brain, which in turn is a
product of the initial morphological conditions implied by genetics
plus the history of interactions.
9) Usually the most significant interactions in children development
is with their parents so that heredity has a second-order effect, not
related directly to genetics.
10) People seldom live among members of the same ethnic group, so
heredity has a third-order effect on their interactions.
11) It is very hard to trace back the causal factors of one's state
of mental capacities down (up?) to its genetical, cultural,
environmental origins.
12) A lot of people have emotional negative reactions towards attempt to
attribute collective properties to some populations. These are left-overs
of the struggle against old class-based societies, colonialism, and
plane ethnic-based hatered.
13) In particular, attribution of properties to genetics, gives rise to
the most hostile reactions, since genetic superiority has been an
excuse for genocyde that took place in this century in Europe.
14) Genetic arguments also contradict ideologies based on the feeling
that modern man can control the universe.
15) All this leads some times to ridicilous opinions based on supression
of some evident facts concerning the nature of people, just because they
condradict some naive variants of socialist/egalitarian dogma.
16) I conclude that genetics, family, culture and personal experience are
the major determinants of intelligence, whatever this word stands for.
Genetics supplies the basic infra-strucuture that may constrain the
space of possible future configuration, but most of the rest is determined
by environmental interacrtions.
17) Some weired thoughts: are people or books the genes of a culture?
Are there any speculative theories about environmental effects on
the genes themselves (not Lisenko type theories when you can "convince"
a tomato to become a carrot).
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Oded Maler, Department of Applied Mathematics and Computer Science,
Weizmann Institute of Science, Rehovot 76100, Israel.
E-mail: oded@wisdom.bitnet / oded@wisdom.weizmann.ac.il /
oded%wisdom.weizmann.ac.il@cunyvm.cuny.edu)
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