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Philosophy / Ancient Philosophy

Introduction to Stoicism: Logic, Physics, and Ethics

The Birth of Stoicism

Stoicism was founded in Athens in the early 3rd century BCE by Zeno of Citium. The name comes from the Stoa Poikile (Painted Porch), the public colonnade where Zeno and his followers met to discuss philosophy. While today the word “stoic” often implies being emotionless or indifferent, the original philosophy was a sophisticated system of logic, physics, and ethics designed to help individuals achieve Eudaimonia (flourishing) in a turbulent world.

Stoicism became one of the most popular philosophies of the Roman Empire, attracting everyone from slaves (Epictetus) to emperors (Marcus Aurelius).

The Three Pillars of Stoic Philosophy

The Stoics viewed philosophy as an integrated “living organism” or an “orchard”:

  1. Logic (The Fence): The rules of reasoning that protect the mind from error and false impressions.
  2. Physics (The Trees): The study of the nature of the universe (the “Logos”).
  3. Ethics (The Fruit): The ultimate purpose—how to live a good and tranquil life.

Stoic Physics: The Rational Universe

The Stoics were materialist pantheists. They believed that the universe is a single, organic, and rational whole governed by an active principle called the Logos (Universal Reason or God).

  • Providence: Because the universe is rational, everything that happens occurs for a reason and according to nature.
  • The World-Soul: Humans, as rational beings, contain a “spark” of the universal Logos. Our task is to align our individual reason with the Reason of the universe.

The Core Ethical Principle: The Dichotomy of Control

The most fundamental practice of Stoicism, famously articulated by Epictetus in his Enchiridion, is the distinction between what is up to us and what is not.

Up to Us (Internal)Not Up to Us (External)
Our opinions and judgmentsOur body and health
Our desires and aversionsOur reputation and status
Our intentions and choicesWealth and possessions
Our own characterThe actions of others

The Stoics argued that unhappiness arises when we try to control things that are external to us, or when we fail to take responsibility for our internal state. To be “stoic” is to focus all your energy on your own character and choices, while accepting external events with Amor Fati (love of fate).

Virtue as the Only Good

For the Stoics, Virtue is the only good. Health, wealth, and fame are not “good” in themselves because they can be used for evil; they are “preferred indifferents” (proēgmena). Similarly, poverty, illness, and death are “dispreferred indifferents.” A wise person (the “Stoic Sage”) understands that their happiness cannot be taken away by fortune, because their happiness consists entirely in their own virtuous character.

The Four Cardinal Virtues

Stoic ethics is centered on the cultivation of four primary virtues:

  1. Wisdom (Prudence): The ability to navigate complex situations logically and calmly.
  2. Justice (Fairness): Treating others with kindness and recognizing the brotherhood of all humans (Cosmopolitanism).
  3. Courage (Fortitude): Not just in battle, but the daily courage to face adversity and speak the truth.
  4. Temperance (Moderation): Self-control and the ability to resist impulsive desires.

Living in Accordance with Nature

”Life in accordance with nature” is the Stoic motto. This means two things:

  1. Human Nature: Living as a rational and social animal. To act irrationally or antisocially (with hate or greed) is to act against your own nature.
  2. Cosmic Nature: Accepting the laws of the universe. When it rains, it is the nature of the universe for it to rain. To complain about it is as futile as complaining that 2+2=4.

By understanding these principles, the Stoic prepares themselves for the more practical applications of the philosophy, which we will explore in the next lesson.