While art's main value is most definitely not bound up in providing explicit moral guidance or detailing specific information, I personally have learned a lot from different authors on this subject--and will be posting some quotes here along these lines.
Having just finished reading World Without End, here are three quotes from or about Edmund--one of the many great characters in the book:
1. "Any man who needs to surround himself with loyal acolytes doesn't really believe in himself, why should I?"I highly recommend this book by the way--not because you can learn a little bit about how to judge other people, but because it's a great story, one of the best ever written.
2. "I never trust anyone who proclaims his morality from the pulpit. That high-minded type can always find an excuse for breaking his own rules. I'd rather do business with an everyday sinner who thinks it's probably to his advantage, in the long run, to tell the truth and keep his promises. He's not likely to change his mind about that."
3. "Edmund had explained to Carris, many years ago, that although customers needed to believe they were buying from a successful business, they would resent contributing to the wealth of someone who appeared to be rolling in money."
(I actually like it better than its much-acclaimed predecessor, The Pillars of the Earth, primarily because of how World Without End ends.)