There is a single definition of success. Look at yourself in the mirror, in the evening, and wonder if you disappoint the person you were at 18, right before people get corrupted by life. Let him or her be the only judge. Not your education, not your wealth, not your standing in the community, not the decorations on your lapel. If you do not feel ashamed, then you are successful.
– Nassim Nicholas Taleb
Earth, Wind, and Fire 