Cleanthes succeeded Zeno as head of the Stoa around 262 BCE and led the school for thirty-two years. He had come to Athens, by tradition, with four drachmas in his pocket and supported himself as a night water-carrier so that he could study by day. He was apparently slow to learn but unshakable in retention; his nickname was the Ass — because, as he reportedly said, only an ass could carry the load Zeno laid on him.
He is the most religious of the early Stoics. Where Zeno's logos is austerely cosmological, Cleanthes' is suffused with personal devotion. His Hymn to Zeus is a real prayer — to a real god whom the Stoics identified with the rational order of the universe, with fate, with the divine fire that pervades and animates all things. The hymn closes with a line that Seneca preserved for Roman posterity by rendering it into Latin (after giving Cleanthes' Greek) at the end of Letter 107:
ducunt volentem fata, nolentem trahunt The fates lead the willing, and drag the unwilling.
The sentence is the Stoic doctrine of fate in eight words. Either you align your will with what happens — and walk with it — or you refuse, and are dragged. There is no third option. The choice is not whether to be subject to fate; it is whether to consent.
He is reported to have died around 230 BCE by deliberate starvation, after refusing to eat during an illness on the grounds that he had already lived long enough and had no further work to do. His successor was Chrysippus, who would systematize the entire Stoic philosophy and earn the saying: Had there been no Chrysippus, there would have been no Stoa.