1) The knowledge I have gathered via my religious studies.
2) The realization that human emotions are fickle and prone to change, so one must never assume how a person feels about you today will remain unchanged.
3) That a person needn't be insane or demon possessed to do something truly evil to another.
4) Always be careful when sharing personal information about yourself..what you say can and may very well be held against you!
5) That being patient, tolerant and polite will bring far better returns in the long run.