Stoicism was a philosophical movement of the Hellenistic period founded by Zeno of Citium (c. 334 – c. 262 BC). Its name comes from the Stoa Poikile, a popular site reputable for the artwork, paintings, and war bounty displayed within it. It was here that the first Stoic Zeno met and taught his followers. Stoicism flourished in Ancient Greece and Rome.

Heads of the Stoic School

Unfortunately, historians do not possess the original writings from the first three major heads of the Stoic school: Zeno, Cleanthes (330 – c. 232 BC), and Chrysippus (279-206 BC). Complete works penned by Stoic proponents only come from the later imperial times in the form of Seneca (4 BC – 65 AD), Epictetus (c. 55-135 AD) and Marcus Aurelius (121–180 AD).

Stoic philosophy included two major phases: Greek and Roman. The former was within Athens where it flourished. Zeno geared Stoicism in the direction of three key areas: ethics, physics (the study of that world), and logic (the study of how to reason about the world). Cynicism, another philosophical school, had a strong influence on Stoic philosophy given Zeno begun his studies under the Cynic Crates (C. 365- C. 285 BC). Cleanthes became the second head of the school in Athens after the death of Zeno. He was a materialist who held that anything that everything must be material, including the soul. Cleanthes was the most religious of the Stoics and he introduced a theological dimension to Zeno’s teachings. He believed that the universe is a living entity, and that God is its soul. The philosopher Chrysippus was the third head of the school, as well as its most influential proponent given his systematization of teachings from Zeno and Cleanthes. He wrote on questions of logic, propositional logic, syllogistic deduction, freedom and determinism, developed an empiricist epistemology, and a materialist ontology.

Stoicism Spreads to Rome

In 155 BC Stoicism found its way to Rome after the heads of the three major schools within Athens (the Stoics, Peripatetics, and Academics) were sent there to assist with diplomatic efforts. Philosopher Diogenes of Babylon (240-150 BC), head of the Athenian Stoic school, proved impressionable, and likely started the process of shifting Stoicism from Athens to Rome. Violent political events in the years 88 to 86 BC also serviced the move. The defeat of the King of Pontus and Athens led to a dispersion of philosophers along with their ideas throughout the Mediterranean. This was followed by the Roman period in which the Stoics begun refining their ideas and putting them into practice in their personal and social lives. Whereas early Greek Stoicism mostly needed to contend with the critiques of other schools (such as the Epicureans and the Cynics), the movement experienced harsh treatment under Vespasian (9-79 AD) and Domitian (51-96 AD). However, it was also warmly received by others, such as Marcus Aurelius (121-180 AD).

Philosophical, Cosmological, and Theological Beliefs

For the Stoics, philosophy was viewed as a way of life over and above simply a body of knowledge. It was not merely a purely academic exercise, but a practice with the goal of self-transformation and living an eudaimonic life.

Stoicism was naturalistic-materialistic holding that all existing things are corporeal, although they also believed in incorporeals (such time, the void, and sayables (meanings)). When speaking of the soul and God, they always saw them as physical entities. God is a corporeal rational principle organizing the cosmos, and an eternal reason which is immanent throughout creation. God is also an intelligent designing fire or breath, which structures physical matter in accordance with a plan. The Stoics believed in a (physical) god which can be deemed pantheistic (part of creation) given its immanence and corporeality.

Stoic cosmology is built upon a division between two classes: active and passive. The active class is identified with reason and is that which acts upon matter. It is referred to as an intelligence, a primordial fire, God, Fate, or Logos. The passive class consists of matter and substance which is acted upon by the intelligent, organizing force. They held that the passive class, consisting of four elements (water, air, fire, Earth), is destroyed and recreated eternally. This cycle repeats itself endlessly, and creation (via a generation of the elements) always begins from a state in which all is fire (called the conflagration), and will end back there once again.

Ethics is the most important feature of Stoic philosophy. They believed that people possess natural propensities to develop morally. Derived from Socrates (c.  470 – 399), the Stoics stressed four cardinal virtues (courage, wisdom, temperance, and justice), and several specific ones within each of these categories. People ought practice these virtues because they are necessary in the pursuit of happiness. They are also practiced through three disciplines: desire (training oneself to desire what the universe allows and not to pursue what it does not allow), action (which is philanthropic focused in that people should develop within them a natural concern for others), and assent (a “mindfulness” in regards to making proper judgments and decisions about what to accept or reject of one’s experience of the world). The idea of eudaimonia denoted the flourishing life of which apatheia (freedom from passion) is an essential part. This did not mean Stoics intended to distance themselves from their emotions or make attempts to suppress them; rather, they divided passions into two categories: unhealthy (fear, pain, pleasure, and craving) and healthy ones (discretion, delight, and willing). People should exercise mindfulness in order to avoid unhelpful and destructive emotions.