STOICISM

Stoicism is an ancient Greco-Roman philosophy teaching that virtue (moral excellence) is sufficient for happiness (eudaimonia), achieved through living according to reason and nature. Stoics distinguish what's "up to us" (judgements, desires, actions) from what's not (external events, others' actions, health, wealth)—focus only on former. Core principles include: accept what you cannot control, fulfil duties according to nature, emotions arise from faulty judgements (vice = ignorance), and cultivate four cardinal virtues (wisdom, courage, justice, temperance). The universe is providentially ordered by divine Logos (reason); everything happens for reason. Stoic practices include: negative visualisation (premeditatio malorum—imagining loss), cosmopolitanism (all humans are fellow citizens), and living in harmony with nature.

Founded Athens c. 300 BCE by Zeno of Citium in Stoa Poikile (painted porch), hence "Stoicism." Early Stoics: Zeno, Cleanthes, Chrysippus systematised philosophy. Middle Stoa: Panaetius, Posidonius introduced to Rome. Roman Stoicism flourished: Seneca, Epictetus (slave-turned-philosopher), Marcus Aurelius (emperor-philosopher). Declined with Christianity but influenced Christian ethics. Contemporary revival through cognitive-behavioural therapy.

Zeno of Citium (founder), Cleanthes, Chrysippus (systematiser), Panaetius, Posidonius (Middle Stoa), Roman Stoics: Seneca, Epictetus, Marcus Aurelius, contemporary: William Irvine, Massimo Pigliucci (modern Stoicism), cognitive-behavioural therapists drawing on Stoic insights.

Virtue sufficient for happiness. Living according to reason and nature. Dichotomy of control: focus on what's "up to us." Emotions from faulty judgements. Four cardinal virtues. Cosmopolitanism and universal brotherhood. Providence and divine Logos. Preferred and dispreferred indifferents. Negative visualisation. Amor fati: love fate. Memento mori: remember death.

Influenced Roman law and natural law theory. Shaped Christian ethics through Paul and Augustine. Contributed to Enlightenment rationalism. Founded cognitive-behavioural therapy precursors. Contemporary revival in popular philosophy. Relevant to resilience and mental health. Influenced military and leadership philosophy. Informs modern virtue ethics and moral psychology.