One of the central tenets of Stoicism is the distinction between what we can control and what we cannot. Pigliucci emphasizes that by focusing our energy on our own actions and attitudes, and accepting what is beyond our control, we can achieve a sense of tranquility and reduce unnecessary stress.

Stoicism teaches that living a virtuous life is the key to true happiness. Pigliucci explains how virtues such as wisdom, courage, justice, and temperance can guide our actions and decisions, leading to a more meaningful and ethical existence.

The book highlights the importance of practical wisdom, or "phronesis," in making sound judgments. Pigliucci provides examples of how Stoic principles can be applied to everyday situations, from personal relationships to professional challenges, helping readers develop a more thoughtful and deliberate approach to life.