Stoicism began in Athens around 300 BCE when Zeno of Citium began teaching in the Stoa Poikile, the painted porch that gave the philosophy its name. Zeno had previously studied under Crates the Cynic, and Stoicism inherited Cynicism's emphasis on self-sufficiency and virtue while abandoning its rejection of social participation. From this Hellenistic seed grew a philosophy that found its most enduring expression in Rome, where three authors became the most widely read Stoic voices: Seneca, Epictetus, and Marcus Aurelius.
Seneca (4 BCE–65 CE) was a Roman statesman, playwright, and advisor to the emperor Nero whose letters to Lucilius became one of the most accessible introductions to Stoic thought, alongside his essay on the shortness of life. Epictetus, born into slavery and later freed, founded a school in Nicopolis and taught that even a person who owned nothing could possess the only true freedom: the faculty of choice. His teachings were recorded by his student Arrian in the Discourses and condensed into the Enchiridion, the pocket-sized handbook that opens with the line "Some things are up to us; others are not." Marcus Aurelius, Roman emperor from 161 to 180 CE, wrote his Meditations as a private journal never meant for publication, a record of self-examination under the heaviest responsibilities a person can bear.
Stoicism flourished in Rome because its emphasis on duty, virtue, and self-discipline matched Roman civic ideals; senators, generals, and emperors found in it a practical philosophy rather than an abstract one. It differs sharply from Epicureanism, which sought serenity through the careful calculation of pleasure, and from Skepticism, which suspends judgment even on ethics. Stoics, by contrast, affirm a rational cosmos and a confident ethics: virtue alone is good, vice alone is bad, and everything else is neither, though some externals are reasonably preferred and others reasonably avoided.