Jay, your thoughts here are quite thought-provoking. I think
we still disagree, though, on the use of the term "constrain."
For me, a constraint is something which inhibits or restraints
potential movement or form. I also believe that infants are born
with an incredible potential for a huge variety of types of human
language, human discourse, human patterns of social interaction,
etc., but the cultural-linguistic settings in which they exist
constrain that potentiality. E.g., infants can discriminate all
potential phonemes; by the age of one year, they are vocalizing using
only the phonemes of their native language, and by the age of
12 years, they are unlikely to learn a second language without an
accent. I think this is also true in the realm of knowing how to
engage in (contextually defined) socially appropriate discourse; most
infants have the potential to become competent within any sociocultural
setting, but that potential is constrained by the actual settings
they live in. By adulthood, it's difficult to become socially "fluent"
in another culture. Thus, I would still maintain that culture is
inherently constraining.
Robin