"I love getting even when I get screwe d by someone... Always get even.  When you are in business,you need to get even with people who screw you.  You need to screw them back 15 times harder.  You do it no only to get the person who messed with you, but also to show the others who are watching what will happen to them if they mess with you  If someone attacks you, do not hesitate.  Go for the jugular."  Donald R. Trump from his 2009 book  "Think Big."