I think the idea of individual differences has been way under-theorized
by the activity theory people I am most familiar with. It is certainly
back in a lot of guises now, one of them being the frequency with
which multivoicedness and Bakthin are conjoined (and not only in
CHAT circles).
In thinking about this issue, am I correct in interpreting your
earlier post as assuming that contributions of phylogenesis to
individual differences are irrelevant?
My problem is that I think the entire issue of what individual means
in the phrase, individual differences, at it appears in psychology
texts (including my own) run seriously counter to the complexities
of the term, individual/solo/etc in xmca disccussions.
mike