Some time ago I was riding on a plane reading "The God Who is There" by Schaeffer and "Truth Decay" by Groothuis, weighing the implications of truth decay in our postmodern culture. There was a young boy and his father seated next to me. I always try to mind my own business while traveling, but the close proximity limits one's ability to avoid eavesdropping. The interaction between this father and son was quite entertaining, yet I could not help filtering their dialogue through the books I was reading.
The boy was talking about aliens, and how, if they found our planet they would probably invade us. The father interjected that if aliens did exist, they probably would not be inclined to invade our planet. To prove his point, the father reversed the scenario on his son. "If we (humans) discovered another planet with life on it, we would not invade them for no reason." The son remarked, "Well, I would." The father smirked slightly and replied, "Well, that's not very nice son."
I find the use of the word nice intriguing. Ultimately, I think the truth the father wished to convey was that his son's action would be wrong (It would be wrong to invade someone for no good reason.) The problem is that our culture no longer recognizes objective moral truth. Any judgment of right or wrong is considered subjective, and our language has merely morphed to snychronize with this trend towards moral relativism.
The problem with a word like nice is that it is neutral. It does not convey an absolute standard. Something could be the right thing to do and not be considered nice at all. Alternately, an action could be considered nice in gesture, but be entirely morally bankrupt. You see, nice has a subjective quality that depends on the perspective of the observer or recipient.
I am not suggesting that we remove the word from our vocabulary altogether. My point is to show an example of the subtle increase of moral relativism in our culture. Philosophical shifts always manifest themselves in art, music, and especially language. We will at times disagree with one another as to what right and wrong ought to be, but we must never reject absolute moral standards altogether. This would lead to total anarchy and is existentially unlivable in a sane world. On a secondary note, we should all take great care that the words we use reflect our values. To the gentleman on the plane that day: If you are not a moral relativist, I suggest you carefully consider how you employ your words. We all should do likewise.