“ He took the doctrines of Zeno and Cleanthes and crystallized them into a definite system; he further defended them against the attacks of the Academy. His polemic skill earned for him the title of the “Column of the Portico.” Diogenes Laertius says, “If the gods use dialectic, they can use none other than that of Chrysippus”; εἰ μὴ γὰρ ᾐν Χρύσιππὄς, οὐκ ἂν ἠν Στοά (“Without Chrysippus, there had been no Porch”) . He excelled in logic, the theory of knowledge, ethics and physics. His relations with Cleanthes, contemporaneously criticized by Antipater, are considered under Stoics. ”