That environmental factors (e.g., level of education, social status, etc.) might play a much bigger part in one's intellectual development is a view of intelligence which is more associated with Multiple Intelligence Theory (M.I.).
M.I. is considered, by some, to be a better alternative for determining intellectual capacity, - but it is a matter of debate. Albeit an intriguing theory, M.I. tends to want to 'redefine' what intelligence is, as opposed to expanding on the classical definition and, given this, I stand with the critics of M.I. who hold that the theory is ad hoc.
That said, I cleave to the notion that one's capacity for intellect is primarily a genetic attribute.
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