"If you don't care, don't post."
I've been in a place where lots of arguing goes on, though I rarely involve myself with the arguments other than to try to end the conflict, this phrase has taught me how to find the root of what I really care about, and after my 4 year journey of discerning morality, it's also taught me how to avoid, find the root of, or solve, almost any conflict that I come across.
What have you learned from the Blockland forums?