This must be a continuation of the
moral relativity debate from another thread. Basically, some people think that morals are God-given and absolute while others think morals are defined by the masses within a society.
Yes, some morals are pretty consistent across cultures. Like murder. It's pretty obvious why murder would be considered immoral.
But some are not consistent across cultures. In some cultures it's immoral to marry first cousins. In other cultures it's expected. In some cultures it's immoral to have pre-marital sex. In others it's widely accepted. In some it's even expected. There are even different sets of morals between sub-cultures within a culture.
And morals aren’t consistent across time. In the US it used to be immoral for women to show a lot of flesh, almost to the extent of some Islamic countries. It’s widely accepted now. Not long ago homosexuality was considered immoral in the US. It is accepted by most people now. People that lived in the 1800's would consider us pretty darned immoral. Can human sacrifices be considered murder? It was common in some cultures in the past, so even murder isn't beyond being moral.
Basically, if we can point to other cultures as being immoral and other cultures can point to us as being immoral then it’s pretty obvious that morals aren’t absolute.