Chrysippus of Soli (279 - 206 BC) was a Greek Stoic philosopher. He expanded the fundamental doctrines of Zeno of Citium which earned him the title of Second Founder of Stoicism. He excelled in logic, the theory of knowledge, ethics and physics. He created an original system of propositional logic in order to better understand the workings of the universe and role of humanity within it. He adhered to a deterministic view of fate, but sought a role for personal freedom in thought and action. Ethics, he taught, depended on understanding the nature of the universe, and a therapy of extirpating the unruly passions which depress and crush the soul. He initiated the success of Stoicism as one of the most influential philosophical movements for centuries in the Greek and Roman world. Of his written works, none have survived except as fragments embedded in the works of later authors like Cicero, Seneca, Galen, Plutarch. He died in 206 BC at the age of 73. Engraving by J.W. Cook, 1825.