8 Philosophers of Stoicism You Should Know

Stoicism was (and is) a practical philosophy that deals with ethics, politics, and social matters. The first of the Stoics began teaching in Athens in the 3rd Century BCE, spearheaded by Zeno of Citium. One of the principal Greek philosophies of the Hellenistic period, Stoicism sought to teach humans how to reach eudaimonia, or happiness. For the Stoics, this could only be reached by following a virtuous life lived “in accordance with nature.”

After a delegation of Greek philosophers visited Rome, Stoicism was widely adopted by the Romans for centuries. Influenced by the teachings of Zeno and his students, some of Rome’s greatest philosophers such as Seneca, Epictetus, and Emperor Marcus Aurelius all called themselves Stoics.

After Alexander the Great died in 323 BCE, several schools of philosophy emerged that attempted to work out how to achieve eudaimonia, or happiness. Stoicism was one of the more famous of these philosophies. Beginning with Zeno of Citium in around 300 BCE, the Stoics covered a range of philosophical spheres: ethics, logic, and metaphysics.

Stoicism’s theory of metaphysics helps to explain its core tenets. The Stoics believed that God and the universe were one entity called “the divine logos” that worked through a kind of divine fire called pneuma. Everything in the universe came from the logos. Planets, stars, humans, and animals were regarded as passive matter, and all of them were subject to the fate determined for them by the divine, rational logos.

As the universe was preordained by the divine logos, the Stoics reasoned that we shouldn’t worry about things that we can’t control. Reacting negatively to an event outside of our control through anger or fear is irrational. Stoicism, therefore, teaches that as a rational being, man should control his emotions to avoid making irrational choices and endangering his virtue.

Virtue is the driving force of Stoicism, consisting of four cardinal ideals; courage, justice, temperance, and wisdom. Stoics believed that evil was not inherent to human beings but simply came from ignorance of the divine Logos and our essential nature. Stoic philosophers didn’t advocate expunging emotion altogether. But by striving for inner peace, they believed we could avoid evil, ignorance, and unhappiness, allowing us to lead a virtuous life.

Stoicism began in Athens when Zeno of Citium established his own philosophical school in around 300 BCE. Before opening his academy, Zeno was a wealthy Phoenician merchant. However, after surviving a shipwreck during a trading voyage, Zeno journeyed to Athens, seeking the best way to live. While standing in a bookshop perusing some philosophical texts about Socrates, Zeno asked the shopkeeper where he could find someone similar. The shopkeeper pointed at a strange hermit-like figure walking past —Crates the Cynic. As a Cynic, Crates rejected material comfort and instead lived an ascetic life without shame for his unkempt appearance.

Despite studying under Crates, Zeno couldn’t shake his self-consciousness about the Cynic lifestyle, so Crates devised a lesson. He ordered Zeno to carry a pot of lentil stew around town. Embarrassed, Zeno attempted to conceal the pot, so Crates swung his cane and shattered the urn. Covered in stew, Zeno ran in shame while Crates crowed “Why run away, my little Phoenician? Nothing terrible has befallen you.” Zeno wanted to create a philosophy that combined Cynic teachings with a more modest and civilized way of living that would bring happiness to its practitioners. After studying under various other philosophers, Zeno began teaching his own ideas from under the Stoa Poikile, a painted colonnade in Athens. Gradually, his students began to grow, and the school of Stoicism was born.

In those early days, Zeno established many of Stoicism’s core ideas, such as the belief that God and the universe were the same entity. He also set Stoicism’s course as a philosophy designed to find “the good life,” lived in accordance with nature and virtue. But it was Zeno’s students who transformed Stoicism into one of the ancient world’s most enduring philosophies.

When Zeno passed away in 262 BCE, Cleanthes succeeded him as the leader of the Stoic school. A former boxer who took pleasure in working with his hands, Cleanthes had come to Athens to learn philosophy. After attending lectures from both Crates and Zeno, Cleanthes gravitated towards Stoicism.

Cleanthes set about developing Stoicism further, unifying his ideas on ethics, logic, and metaphysics into a single philosophy. He acknowledged the existence of the soul, incorporating the concept into Stoic ideas about how life worked. Building on Zeno’s idea of the divine logos, Cleanthes suggested that the sun was made from the divine fire, or pneuma, that made up the universe. He reasoned that because the sun gave life to things on Earth, it must be an extension of the divine logos.

Cleanthes’ stance on ethics was different from Zeno’s. He believed that pleasure conflicted with nature and that emotions were weaknesses that lacked the strength of the souls created by the divine logos. Instead of striving for a life of happiness, Cleanthes advocated a life of consistency. For Cleanthes, the only consistent quality was reason and logic. This meant accepting the universal reason of the divine logos and submitting to fate.

Chrysippus: The Second Founder of Stoicism

While Zeno and Cleanthes established Stoicism, it was Chrysippus who truly developed the philosophy into the one that would captivate the Romans. Chrysippus came to Athens to study and was one of Cleanthes’ foremost pupils, succeeding as head of the Stoic school when his mentor died in 230 BCE.

The Stoic idea of fate made huge strides under Chrysippus, who believed that fate determined everything in the universe. Chrysippus used his own revolutionary system of logical propositions to illustrate that because things can only be true or false, nothing can happen without a specific cause. Rival philosophers stated that a deterministic universe negates the idea of free will but Chrysippus disagreed, explaining that there were simple fates and complex fates. Human actions could influence the course of supposedly unavoidable events and affect the consequences.

We may experience something like illness due to preordained fate, but our reactions to the event are completely our own, giving us agency. These reactions form part of our inherent nature bestowed by the divine Logos. Under Chrysippus, Stoic ethics shifted away from the impersonal, rational goals of Cleanthes into something more individual. For Chrysippus, the goal of life became living in accordance with our inherent rational observations of nature.

However, like Cleanthes, Chrysippus also advocated taking complete control of our emotions to reach a state of inner peace called ataraxia. Chrysippus believed that we can use reason and logic to prepare for situations where we face passionate emotions, so that they don’t overwhelm us.

With Stoicism now set on a course that would turn it into the dominant philosophy of the later Roman Empire, Chrysippus died in 206 BCE. Many accounts claim that after drinking too much wine that hadn’t been watered down, Chrysippus laughed himself to death.

From around 200 BCE, the Roman Republic began challenging the Greek nations for dominance in the Mediterranean, subjugating the region in 146 BCE. Before and after, Greek ideas had influenced the Romans, who built upon the foundations of the Hellenistic World. One of the Greek concepts that the Romans took to was philosophy, and three contenders attempted to gain traction in Rome.

In around 155 BCE, the Greeks dispatched three competing philosophers to Rome to protest against a heavy fine imposed by the Romans. These philosophers were Carneades the Skeptic, Critolaus the Peripatetic, and Diogenes of Babylon, who represented the Stoics. Each philosopher made a speech hoping to convince the Roman Senate to overturn the fine.

Carneades made two speeches; one praising the Roman justice system and one refuting it. This disturbed the Romans, and he was dismissed. Critolaus argued that pleasure was a vice, which didn’t sit well with the assembly. But Diogenes’s speech was praised for its calm and modest delivery, and the Romans began to take an interest in Stoicism.

The fine was dropped, and Diogenes returned to Athens. He remained in his position as head of the Stoic school until he died in around 140 BCE. Although he was a prolific writer, Diogenes’ greatest achievement was bringing the ideas of Stoicism to Rome.

Panaetius of Rhodes: The Radical Stoic

While Diogenes of Babylon may have introduced the concepts of Stoicism to Roman minds, it was Panaetius of Rhodes who truly dispersed these ideas. Born in Rhodes in around 185 BCE, Panaetius moved to Athens in his youth and began learning from Diogenes and other Stoic philosophers.

After learning what he could under the Stoics, Panaetius became an acquaintance of a visiting Roman statesman, Scipio Aemilianus. When Scipio returned to Rome, Panaetius followed his patron and began writing several prominent Stoic texts. These writings began to circulate in Rome, influencing powerful politicians such as Cicero.

Panaetius was something of a radical within Stoicism, rejecting many traditional ideas and developing his own theories. He overhauled Stoic metaphysics by simplifying it. Before Panaetius, most Stoics had believed that the universe’s base element was pneuma, the divine fire. They claimed the universe would go through a cyclical process of destruction and rebirth called the conflagration, when everything would be wiped clean and the universe would start again from scratch. Panaetius disagreed with this fatalistic idea and stopped teaching it.

Panaetius also clashed with another traditional Stoic idea: apatheia or the practice of controlling emotions. He argued that some emotions and pleasures did not oppose living in accordance with man’s rational nature. Given that Panaetius heavily influenced the next few Roman Stoics, he is undoubtedly one of the most important thinkers of the school. Panaetius was one of the Stoic school’s last masters and died around 110 BCE.

Seneca is one of the most famous and controversial Stoic philosophers. One of Rome’s greatest writers, Seneca was born in Spain in around 4 BCE. He moved to Rome in his youth to study philosophy and was taught by the Stoic Attalus. He gradually worked his way up to become a clerk and eventually a Senator.

But Seneca’s life was full of persecution and paradoxes. In 41 CE, Seneca was exiled to Corsica by Emperor Claudius after accusations of adultery with the sister of the former emperor, Caligula. Eight years later, Seneca was recalled to Rome by Claudius’ wife Agrippina, who wanted the philosopher to become the tutor for her son, Nero. Nero, of course, became one of Rome’s most notorious Emperors, infamous for his cruelty. As a Stoic, Seneca was philosophically committed to living a virtuous life but also advised a despot and accumulated a vast amount of wealth. It’s difficult to reconcile Seneca’s actions with some of the values of Stoicism. In 65 CE, Seneca was implicated in a plot to depose and kill Nero.

Although the charges were undoubtedly false, the incensed, paranoid Nero ordered his former mentor to kill himself. Seneca obeyed, slashing his wrists and taking poison. Throughout the whole ordeal, Seneca’s Stoic mindset reflected the principle of apatheia. He controlled his emotions and accepted what fate had in store.

Throughout his career, Seneca wrote a series of letters to friends and family. Many of these letters, especially those collected in On the Shortness of Life, spoke of not worrying about events outside of our control. Seneca routinely comforted his family members when bad things happened to him, rather than reacting emotionally himself. While opinions on Seneca are often conflicted, no one can deny that the philosopher was a model of Stoic control in the face of extreme adversity.

One of Stoicism’s most famous practitioners, Epictetus was born in modern-day Turkey in 55 CE, a cripple and slave to a wealthy statesman. Despite this, Epictetus was allowed to study Stoic philosophy. After earning his freedom Epictetus began teaching philosophy. However, in 93 CE Emperor Domitian outlawed philosophy, so Epictetus left Rome to found a philosophical academy in the Greek city of Nicopolis. Epictetus adopted a simple lifestyle and shunned material goods, devoting himself to teaching Stoicism.

Despite his difficult start in life, Epictetus embodied the Stoic spirit. He taught his pupils not to complain or worry about events that they could not control, arguing that nothing had been taken from them that did not belong to the universe. Epictetus sought to teach Stoicism as a practical philosophy to be used in real life, believing that humans had a destiny as rational creatures that was bequeathed by the gods. Using our rational faculties, it was our responsibility to fulfill this purpose through living with virtue and in accordance with our nature.

For Epictetus, the Stoic idea that evil was not intrinsic to human beings was one of the most important concepts. Evil only came about through ignorance and irrational behavior. Epictetus believed that our drive to live virtuously should affect not just us, but also our family and countrymen. Epictetus argued that we should be willing to aid our fellow man, and he embodied this principle through his deeds. When he was an old man, Epictetus willingly adopted the abandoned child of a friend and cared for the boy as if he was his own. Epictetus was a model Stoic, and his teachings would go on to influence one of the most famous philosophers of all time.

Marcus Aurelius’ Meditations is one of philosophy’s most famous texts. Written as a series of daily assertions, Meditations is an ensemble of Stoic maxims that Emperor Marcus Aurelius lived by during his reign. The inspiration for these journals came from Epictetus’ Discourses, which heavily influenced Marcus Aurelius as he studied philosophy in his formative years.

Marcus Aurelius had a troubled reign, inheriting the throne in 161 CE. Aurelius faced several famines and wars with the Parthians and Germanic tribes before facing an unsuccessful coup in 175 CE. He lost his wife Faustina soon after. For several years, Aurelius appointed his son Commodus to rule alongside him, before passing away in 180 CE.

Throughout these trials, Aurelius reflected on events through his Meditations, repeating Stoic mantras to keep himself grounded. Aurelius frequently talks about looking inwards, evaluating his judgments to find his natural place within the universe, and living in accordance with his nature. He advocated a version of apatheia, resisting the urges of emotion as an irrational response to a crisis. Instead, Aurelius tried to approach problems with rational thinking and the sense of inner calm that comes with controlling emotions. Aurelius tells himself not to worry about events that are outside of his control, attributing the path of events to the chain of fate that comes from the universe.

Aurelius tried to rule according to the cardinal virtues of the Stoics: courage, justice, temperance, and wisdom. He was considered to be the last of Rome’s “Five Good Emperors” according to Niccolo Machiavelli. The Meditations has been praised as one of Stoicism’s seminal works for centuries and it still influences politicians and thinkers to this day.