Be nice to people, as long as they are certified nice.
I remember watching "Fruits Basket" the animation, and listened to the story of "The Foolish Traveler". This particular traveler, had a very good heart. Always wanting to help people, to the extend that he was manipulated by the people he met in his travel. He gave away all his possessions, after listening to their stories, even though they were lying. In the end, as he got not even a single article of clothing on him, he went into the jungle. There, he got tricked by the demons in the jungle, who ate everything save his head. The demons said, "Thank you for your kindness. We have a present for you." The traveler, since he never asked anything in return for his kindness, and never got anyway, was very happy. He keep on saying, "Thank you, thank you. I've never got a present before. Thank you, thank you." He said those words so happily, as he was dying. The present the demons left was a piece of paper, with "Stupid" written on it.
Lesson of the story: DO NOT BE NICE TO PEOPLE UNLESS THEY GOT PROOF THAT THEY ARE NICE TOO.
