Cleanthes died in -230.

Cleanthes was born in -330.

There were 7 successive leaders of the Stoic school, after which there seems only to have been prominent writers but no official leader.

1. Zeno of Citium

2. Cleanthes of Assos

3. Chrysippus of Soli

4. Zeno of Tarsus

5. Diogenes of Babylon

6. Antipater of Tarsus

7. Panaetius of Rhodes

Friedrich Solmsen has written:

'Kleine Schriften' -- subject(s): Ancient Philosophy, Greek philology, Philosophy, Ancient

'The Eleatic One in Melissus' -- subject(s): Melissus, Eleatics

'Hesiod and Aeschylus' -- subject(s): Criticism and interpretation, Gods, Greek, in literature, Greek Religious drama, Greek literature, History, History and criticism, Influence, Influence (Literary, artistic, etc.), Mythology, Greek, in literature, Religion, Religious drama, Greek, Tragedy

'Antiphonstudien' -- subject(s): Ancient Oratory, Ancient Rhetoric, Oratory, Ancient, Rhetoric, Ancient, Trial practice

'Two crucial decisions in Herodotus' -- subject(s): Ancient History, Historiography, History, History, Ancient

'Plato's theology' -- subject(s): God, Religion

'Cleanthes or Posidonius?'

'Electra and Orestes' -- subject(s): Orestes (Greek mythology), Electra (Greek mythology)

The ancient Greek astronomer Aristarchus is the earliest person known to have written about the heliocentric model of the solar system. Ideas like this do not emerge in a vacuum; there are other, earlier observers whose names have not survived the 23 centuries since, who shared or contributed to the concept.

Aristarchus' ideas were not without some controversy; the Stoic philosopher Cleanthes wanted Aristarchus tried on charges of heresy. And the math-heavy idea-driven concept of the heliocentric theory was considerably at odds with the "You can see it with your own eyes!" geocentric model argued by Aristotle.

Like modern politicians, Aristotle was a good debater, whose simple explanations persuaded people to adopt obviously-true ideas that would not be proven false for another 15 centuries. And yet in astronomy, in medicine, in physics, in chemistry, in everything Aristotle wrote about, his ideas were wrong-headed and blind.

After Aristotle, it took 1800 years for Copernicus to revive the heliocentric model of the solar system.