Smoking one cigarette will not jeopardize your health. Taking heroin once will not make you addicted. One piece of cake won’t make you fat, and skipping one assignment won’t ruin your career. But in order to stay healthy and employed, you must treat (almost) every episode as a reflection of the general need to resist these temptations. That’s where conscious self-control comes in, and that’s why it makes the difference between success and failure in just about every aspect of life.