Discourses, "To Those Who Are Desirous of Passing Life in Tranquillity" (§2)

“What then is the reason of this? The reason is that we have never read for this purpose, we have never written for this purpose, so that we may in our actions use in a way conformable to nature the appearances presented to us; but we terminate in this, in learning what is said, and in being able to expound it to another, in resolving a syllogism, and in handling the hypothetical syllogism.”