 Augustine, moreover, is adapting and developing earlier Greek views. In Book XII of his Literal Commentary on Genesis, he offers an extensive analysis of vision that relies heavily on Stoic theory. In both theories, vision depends on the active role of the perceiver’s pneuma (Greek) or spiritus (Latin), “breath” in its original meaning and for the Stoics a kind of hot gaseous body, but for Augustine something immaterial. (The same words, not insignificantly, are used in the Christian scriptures for the Holy Spirit). Vision occurs when the pneuma extends through the optic nerve and the eye to the object, either by reaching out through the pupil to make contact with the object directly (as on Augustine’s theory) or by pricking and tensing the intervening air beginning at the pupil into a cone with its base at the object (as on the Stoic theory). The words that the Stoic Chrysippus uses for the extension of the visual cone to the object are the Greek verb enteinein and noun entasis (Diogenes Laertius VII 157), which are cognate with the Latin intendere and intentio. So if our goal was to find not just a continuous transmission of technical terminology for intentionality, but cognates of intentio, we could trace it back at least to Greek theories of vision in the third century bce, if not still earlier extromission theories of vision. (For further discussion of Augustine’s theory, as well as the history of the terminology, see Caston 2001.)