Logic as a whole being divided into rhetoric and dialectic: rhetoric was defined to be the knowledge of how to speak well in expository discourses and dialectic as the knowledge of how to argue rightly in matters of question and answer. Both rhetoric and dialectic were spoken of by the Stoics as virtues for they divided virtue in its most generic sense in the same way as they divided philosophy into physical, ethical, and logical. Rhetoric and dialectic were thus the two species of logical virtue. Zeno expressed their difference by comparing rhetoric to the palm and dialectic to the fist.