Stoic Pneuma

The Stoa took pneuma — breath — and made of it a physics. Pneuma is the designing fire mingled with air; its tension (tonos), the balance of inward and outward force, accounts for the structural and qualitative differences between things. Margaret Graver: “For the substance they call pneuma, ‘breath’ or ‘spirit,’ incorporates within itself a set of structural principles which are linked to the structure and organization of the universe as a whole” (Graver 2007, ch. 1). Variations in tension impart “hardness to stones, whiteness to silver, and at higher levels the sophisticated properties of plants and animals” (Graver 2007, ch. 1).

The doxography preserves the gradation: a hektikon pneuma sustains stones, a physikon nurtures plants and animals, a psychikon confers sensation and movement (Long & Sedley 1987, §47, citing Galen). On this doctrine psychē is not a separate substance but “the entire stretch of pneuma present in a human or animal” (Graver 2007). Inwood traces the Stoic theory of mental dunamis to a “tonikē dunamis of the mind” — the tonos of one’s pneuma is the material substrate of impulse, assent, and presentation (Inwood 1985, citing Philo and Arius Didymus).

The Stoic doctrine is the first fully articulated theory in the West of a single material-spiritual continuum: a graded breath that is at once gas and god. It is the doctrine into which the Hellenistic world’s pneuma — Septuagintal, Pauline, Hermetic — flowed.

Relationships

• pneuma
• psyche
• logos
• prosoche-stoic
• world-soul
• plotinus

Primary sources

• graver-stoicism-emotion (Graver 2007)
• long-sedley-hellenistic-philosophers (Long & Sedley 1987)
• inwood-ethics-human-action (Inwood 1985)