But how do we know what the "right" ways to present yourself are? It used to be that if you were a white kid in the US and you played with black kids, other whi

But how do we know what the "right" ways to present yourself are? It used to be that if you were a white kid in the US and you played with black kids, other white kids would treat you badly. I presume we all agree that this is not good behavior, and not good for society. But can you clearly delineate between this, and between kids bullying other kids because they are wearing the wrong colors? I understand that we have to realistically look at the effects these changes have on individuals. But I don't think that we have reached any kind of "optimal social rules". Deciding to stop right here and now seems arbitrary, and I'm reasonably certain that there have always been people making this exact argument for any kind of change.