apcragg is probably referring to social mores and the social compact. Ultimately there are conventions, explicit or otherwise, that compel our social interactions.
> Ultimately there are conventions, explicit or otherwise, that compel our social interactions.
I agree, but as far as I know in the US the spirit behind such interactions is pretty much described in the constitution, and the first amendment makes it very clear that freedom of opinion/expression is paramount, no matter what.