Against the Epistle of Manichæus, Called Fundamental 18
18 The Understanding Judges of the Truth of Things, and of Its Own Action PL 42, 183
What, then, must be said of the power of perceiving truth, and of making a vigorous resistance against these very images which take their shape from impressions on the bodily senses, when they are opposed to the truth? This power discerns the difference between, to take a particular example, the true Carthage and its own imaginary one, which it changes as it pleases with perfect ease. It shows that the countless worlds of Epicurus, in which his fancy roamed without restraint, are due to the same power of imagination, and, not to multiply examples, that we get from the same source that land of light, with its boundless extent, and the five dens of the race of darkness, with their inmates, in which the fancies of Manichæus have dared to usurp for themselves the name of truth. What then is this power which discerns these things? Clearly, whatever its extent may be, it is greater than all these things, and is conceived of without any such material images. Find, if you can, space for this power; give it a material extension; provide it with a body of huge size. Assuredly if you think well, you cannot. For of everything of this corporeal nature your mind forms an opinion as to its divisibility, and you make of such things one part greater and another less, as much as you like; while that by which you form a judgment of these things you perceive to be above them, not in local loftiness of place, but in dignity of power.
Et quoniam quaesivi unde mihi probet, nunc quaero unde ipse cognoverit. Si dicit sibi esse revelatum a Spiritu sancto, suamque mentem divinitus illustratam, ut ea quae dicit, certa et manifesta cognosceret; ipse significat quid intersit inter cognoscere et credere. Ipse enim cognoscit, cui apertissime ista monstrantur: eis autem quibus haec narrat, non cognitionem insinuat, sed credulitatem suadet. Cui quisquis temere consenserit, Manichaeus efficitur; non certa cognoscendo, sed incerta credendo; quales nos imperitos adolescentulos aliquando decepit. Debuit ergo non nobis polliceri scientiam, neque manifestam cognitionem, neque ad id quod quaeritur, sine ulla ambiguitate perventionem; sed dicere potius sibi ista esse monstrata, illos autem quibus narrantur credere sibi debere quae nesciunt. Sed si hoc diceret, quis non ei responderet, Si ergo incognita crediturus sum, cur non ea potius credam, quae jam consensione doctorum indoctorumque celebrantur, et per omnes populos gravissima auctoritate firmata sunt? Hoc ille metuens ne sibi diceretur, offundit nebulas imperitis; primum pollicens rerum certarum cognitionem, et postea incertarum imperans fidem. Cui tamen si hoc dicatur, ut saltem vel sibi haec doceat esse monstrata, similiter deficit, et hoc quoque ut credamus jubet. Quis ferat tantam fallaciam tantamque superbiam?