This volume is a revised translation of the complete text of Book Seven about Zeno of Citium and the Stoics, taken from The Lives and Opinions of Eminent Philosophers written around AD 230 by the Graeco-Roman author Diogenes Laertius. The Life of Zeno is accompanied by a complete summary of Stoic philosophy, addressing the three branches of Logic, Ethics, and Physics. Alongside the Life of Zeno are accounts of other Stoics in the Lives of Aristo, Herillus, Dionysius, Cleanthes, Sphaerus, and Chrysippus. The books by the early Stoics have all been lost, and this text by Diogenes Laertius thankfully preserves an important range of quotations and references. It is an invaluable resource for those who adopt Stoic philosophy as their way of life. The translation is supported by an Introduction, Glossary of Names, Notes and Index.