i think the sign means several things. first it could be talking about your school work like if someone is failing in class then they are hurting their own chances of succeeding in life. i think mr hsu my technology teacher put it up there because he wants to show us that one should not hurt themselves instead they should work on helping themselves and possibly others. hmmm lets see one time i had a friend who copied from a student on the CATs. i looked at him and i just thought how he can live with cheating. i talked to him after class i asked hey why did you cheat dont you know you are going to get caught? he replied hah they will never catch me. besides its not like im hurting myself instead im helping myself ecause im giving myself good grades. well i thought what is wrong with him. next day he and the student he copied were sent to the principle. i dont think that incident affected me much. the incident affected the student who was being copied from because he now was being treated as a cheater. the copier was also affected because now he has to take lower classes than everyone else.