If you can’t say anything nice, then don’t say anything at all.” Sounds familiar, right? How about “Share your toys with others!” or “Play nice!” No matter where you come from, we all remember hearing those sayings when we were growing up. That’s because being nice is a quality that’s instilled in us all from the very beginning from our mothers, teachers, and elders. While being nice, or rather polite, is a prized quality and even expected quality in a society that values altruism, the truth is that being “nice” can actually be very bad for you. Actually, being nice could even kill you! Now, let me explain myself… For…