A variation: (my) self-awareness is defined more by (my) failures than by successes (with the exception of having children). Failure is painful and, in general, rational people seek to avoid pain. But fear/pain - and the absolute certainty that we will experience both - shapes our attitude and behavior. Is it pessimism to expect fear/pain? Is it optimism to seek sex/wealth (greed)? Methinks both are the human condition, and both make life worth living.