What exactly is self-control? Self-control involves overriding an impulse to align with an established standard of what's considered appropriate. It consists of three components: the urge, the action of overriding the impulse, and the standard defining what is appropriate. For instance, when you see a doughnut, you experience the urge to eat it. Overriding that impulse is the second step, while the third involves considering the standard—maintaining good health, in this case, and recognizing that indulging isn't beneficial.

We know that 50% of the time, we fail to control our impulses. Self-control is primarily facilitated by the prefrontal cortex. The three key aspects of self-control include monitoring, establishing standards, and possessing the strength to resist impulses. Monitoring involves keeping track of behaviors, like monitoring weight. Standards refer to reference points or norms that guide behavior, akin to societal laws or personal principles. Strength is the ability to resist impulses, which can be developed like a muscle through practice.

Self-control functions similarly to a thermostat, maintaining a baseline or homeostatic state, adjusting as necessary to return to this baseline. The cybernetic theory, which involves steering and navigating through feelings, thoughts, and behaviors, includes phases of testing, operating, testing again, and exiting, in a continuous loop of assessment and action.

Strategies for enhancing self-control include focusing on promotion, aiming for success, or prevention, striving to avoid mistakes. Implementation intentions, or "if-then" plans, are practical strategies to reinforce self-control. For example, setting a rule that if one wakes up, then exercise will follow, or if one overeats, the next meal will be skipped. These strategies are especially useful in combating the poor decision-making that often accompanies mental exhaustion or stress, suggesting that for significant decisions, one should "sleep on it" to ensure clarity and sound judgment.