sometimes people lie so effectively that you really donot know what you have seen with your own eyes was not true.But why do people lie? to achieve some respect ,to cheat or they think that it wont be discovered.Even if you discover it sometimes you feel so bad for the person concerned that you never show it to him/her that you the truth it is just the right thing to do in the paticular situation.But you wish that you were taken into confidence then you might have helped.