the
idea that you can ask somebody to pay for you (for
something like
food or a drink) and tell them that you will pay them back, though you have no intention to pay them back at all
Pay back theory in action:
Mike: "Hey Jason, I
don't have any
money on me, so could you pay for me when we
eat today? I'll pay you back... "
Jason: "Yeah i guess"
Mike: "Ok, Thanks!" (screw that, i'm not paying him a penny)