If you never read The Gift of Fear and Other Survival Signals that Protect Us From Violence. Please get a copy... As the author says... "True fear is a gift. Unwarranted fear is a curse."

http://www.amazon.com/Other-Survival-Signals-Protect-Violence/dp/0440508835/ref=sr_1_1?s=books&ie=UTF8&qid=1367977008&sr=1-1&keywords=Gavin+De+Becker+%E2%80%93+The+Gift+Of+Fear.