In Dante's Inferno, the deepest part of Hell was reserved for traitors--traitors to friends, hospitality, God, etc. Our culture values loyalty; bonds of friendship or family are viewed as sacred.
At many colleges (including Indiana University), rules are supposed to be upheld on an Honor System. If you catch another student cheating, you are supposed to tell on the student. Same is true for drinking and other transgressions (Mr. Assistant Dean, I have some bad news about the fraternity...). Our culture values rules; they are there for a reason, and obviously, cheating is, by most standards, unethical.
So I'm at an interview for a scholarship in Bloomington, and on the first night of the interview weekend a group of the finalists and a couple professors eat dinner together. One of the professors asked us the question of what would we do in the above situation. I said I wouldn't do in my friend, even if I thought he or she was acting unethically. What do you guys think? Further, is there such a thing as universal moral principles or are all ethics relative?
Most important question, did I get the scholarship?