The Enchiridion (handbook) by Epictetus. It’s really a summary of a single idea, but the most valuable idea I have encountered- how to recognize that the hards

The Enchiridion (handbook) by Epictetus. It’s really a summary of a single idea, but the most valuable idea I have encountered- how to recognize that the hardships and problems we face mostly come from failing to identify what we actually control, and mistakenly focusing our efforts and concerns on what we can’t control while neglecting what we can.