>If culture is the only difference,
>then why would a black
>person who grew up in
>a totally white setting/culture, etc.,
>and never known any black
>culture/setting NEVER be considered white?
>and a white person who
>grew up in a totally
>black culture/setting would never be
>considered black?

Racialism is a characteristic of our culture(s).

>I understand that
>they wouldn't be, but that
>kinda says that there is
>more to it than just
>culture- that the physical aspects
>(or genetic) do have some
>relevance, even if it is
>simply bc society has ascribed
>that significance to it.

The cultural significance of those genetic traits is a consequence of the prior belief in that very significance.