SVF I.135
- Stoic
- Zeno of Citium
- Ancient source
- Diogenes Laërtius, Lives of Eminent Philosophers, Book VII — DL 7.157
- Source language
- Ancient Greek
- Source status
- Testimonium
Original — Ancient Greek
Ζήνων δὲ ὁ Κιτιεύς … πνεῦμα ἔνθερμον εἶναι τὴν ψυχήν. τούτῳ γὰρ ἡμᾶς εἶναι ἐμπνόους καὶ ὑπὸ τούτου κινεῖσθαι.StoicOs Translation
Zeno of Citium … [holds] that the soul is warm breath (pneuma); for by this we are ensouled with breath, and by this we are moved.
Context
Diogenes Laërtius, compiling around five centuries after Zeno, summarises Stoic psychology in his doxography of the school. He names Zeno directly for this doctrine of the soul; von Arnim prints the sentence with an ellipsis for words he omits.
Source notes:Greek text verified against H. von Arnim, SVF I (1903), no. 135, p. 38 (scanned page). The ellipsis (…) is von Arnim's own: he omits intervening words of Diogenes' sentence.
What the source actually tells us
This testimony reports that Zeno held the soul to be warm pneuma — breath permeated with vital heat — and that breath explains both life and movement. It is a doxographic report in Diogenes' words, not a quotation from one of Zeno's books.
Philosophical meaning
For Zeno the soul is not an immaterial ghost but a physical, warm breath continuous with the fiery pneuma of the cosmos. Mind and body belong to one nature — the same rational, living stuff at different degrees of tension. Later Stoic psychology and its therapy of the passions grow from this physical picture.
Scholarly uncertainty
Other witnesses transmit related but differently worded formulas for Zeno's doctrine of the soul (von Arnim gathers several under nos. 134–141, including Galen and Tertullian). The doctrine is securely Zeno's; the precise formula varies by reporter.
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About this edition
StoicOs Ancient Library is a developing multilingual digital study edition of surviving early Stoic material. The Stoicorum Veterum Fragmenta assembled by Hans von Arnim provides the traditional reference framework. StoicOs distinguishes carefully between fragments, testimonia, later reports and interpretation. StoicOs translations are prepared from the surviving ancient-language sources where available.