Yet today's Western laws decree monogamy. The moral sense of coal corporations and environmentalists isn't the same. If so, America is the most immoral nation, since it's the richest. The problem with proclaiming a universal truth is that someone, somewhere, lives by an opposing standard. Personally, I don't think there are fixed answers to moral questions.
Views vary with each individual.
Our feelings steer us into certain outlooks - liberal or conservative, conformist or rebel, etc. As Shakespeare said in II Henry IV , the wish is father to the thought. Life is an onrushing tangle of moral puzzles. On our editorial page, we spell out the moral stances that seem right to us - but we don't declare that they're universal maxims which everyone should obey. The choice between the assumptions makes all the difference in the way we view ourselves as a species.