Iamblichus: On the Mysteries · 147 of 218 · tr. Thomas Taylor
Chapter IV
If, however, it be necessary, dismissing these particulars, to speak what appears to me to be the truth, you do not rightly infer “ that a knowledge of this mathematical science [143] cannot be obtained, because there is much dissonance concerning it, or because Chæremon, or some other, has written against it .” For if this reason were admitted, all things will be incomprehensible. For all sciences have ten thousand controvertists, and the doubts with which they are attended are innumerable. As, therefore, we are accustomed to say in opposition to the contentious, that contraries in things that are true are naturally discordant, and that it is not falsities alone that are hostile to each other; thus, also, we say respecting this mathematical science, that it is indeed true; but that those who wander from the scope of it, being ignorant of the truth, contradict it. This, however 318 happens not in this science alone, but likewise in all the sciences, which are imparted by the Gods to men. For time always proceeding the divine mode of knowledge becomes evanescent, through being frequently mingled and contaminated with much of what is mortal. This divine mode is indeed [in astrology also], and a certain clear indication of truth, though it is but small, is at the same time preserved in it. For it places before our eyes manifest signs of the mensuration of the divine periods, when it predicts the eclipses of the sun and moon, and the concursions [144] of the moon with the fixed stars, and when the experience of the sight is seen to accord with the prediction. Moreover, the observations of the celestial bodies through the whole of time, [145] both by the Chaldeans and by us, testify that this science is true. Indications, also, more known than these might be adduced, if the present discussion was precedaneously about these particulars. But 319 as they are superfluous, and do not pertain to the knowledge of the peculiar dæmon, I shall, as it is fit so to do, omit them, and pass on to things more appropriate than these.
Themes
◆Apophatic Theologytheology
Describing the divine only by negation—God transcends all positive categories and concepts; the via negativa.
The text uses negation to describe the divine mode of knowledge as evanescent and contaminated by mortality.
Augustinian and Plotinian doctrine that evil has no positive being of its own but is a lack, distortion, or absence of the good — denying ontological dualism while preserving moral seriousness.
Doubts and ignorance are described as hostile forces that contradict the truth rather than positive entities.