My definition of success is to live your life in a way that causes you to feel a ton of pleasure and very little pain - and because of your lifestyle, have the people around you feel a lot more pleasure than they do pain.
The secret of success is learning how to use pain and pleasure instead of having pain and pleasure use you. If you do that, you're in control of your life. If you don't, life controls you.
The truth is that we can learn to condition our minds, bodies, and emotions to link pain or pleasure to whatever we choose. By changing what we link pain and pleasure to, we will instantly change our behaviors.