Newtons 3rd law states "every action as a equal opposite reaction". I wonder if this applies to people?! Most of us just run through life regardless of the route we take just too focused on the destination. Well lemme pop your bubble, the only destination in our lives is at the end of it; the grave! Life itself is a journey, sure there are pit stops but a journey that starts at birth and ends at death. Its this journey that makes us who we are and who we become.
Karma does have a little play in our lives. its simple really if your nice to someone someone is gonna be nice to you. Sure there are some pricks you cross that u really wanna beat up but the smart thing to do is just let it go because he's gonna get his from someone some where.Same goes for the principle of helping people. Don't help people because you have to, help em because you want to.
It doest matter who your helping or if the person is great full. Just help him because its gna come back to you in a good way. We all have to strike a balance, nature itself fights for balance so rest assured whatever you do in life its gna come back some way :) ; good or bad depends on what ou did.