Effectively this means that there is no such thing as right and wrong and what we are left with is shallow consensus (as opposed to a reasoned consensus) at bes

Effectively this means that there is no such thing as right and wrong and what we are left with is shallow consensus (as opposed to a reasoned consensus) at best, and application of force at worst. I think that society defines morality - society defines what is wrong and what is right, and its criteria is fuzzy and shallow and unreasoned, and fluctuates over time. Since society is an aggregation of individuals, a society's definition of right and wrong is an aggregation of it's members definition of right and wrong (sometimes enforced by law.) Slavery becomes right, because I'm a sociopath with a gun. That's effectively what happened in the 18th century in Europe - it wasn't considered a problem then, but it is now because people's (and therefore society's) outlook on slavery has changed. I don't think that the fact that society decides what is right and wrong is right (as in, it doesn't square with my own personal definition of what is morally right), but I can't think of more accurate definition that is also practical (and practicable.)