to have written a treatise on the astrolabe. Writings Of his reputedly numerous writings, only his commentary on Aristotle's De Interpretatione survives intact. A commentary on Porphyry's Isagoge may also be his, but it is somewhat corrupt and contains later interpolations. In De Interpretatione, Ammonius contends that divine foreknowledge makes void the contingent. Like Boethius in his second Commentary and in The Consolation of Philosophy, this argument maintains the effectiveness of prayer. Ammonius cites Iamblichus, who said "knowledge is intermediate between the knower and the known, since it is the activity of the knower concerning the known." In addition, there are some notes of Ammonius' lectures written by various students which also survive: On Aristotle's Categories (anonymous writer) On Aristotle's Prior Analytics I (anonymous writer) On Aristotle's Metaphysics 1–7 (written by Asclepius) On Nicomachus' Introduction to Arithmetic (written by Asclepius) On Aristotle's Prior Analytics (written by John Philoponus) On Aristotle's Posterior Analytics (written by John Philoponus) On Aristotle's On Generation and Corruption (written by John Philoponus) On Aristotle's On the Soul (written by John Philoponus) There is Greek-language work called Life of Aristotle, which is usually ascribed to Ammonius, but "is more probable that it is the work of Joannes Philoponus, the pupil of Ammonius, to whom it is ascribed in some MSS." English translations Ammonius: On Aristotle Categories, translated by S. M. Cohen and G. B. Matthews. London and Ithaca 1992. Ammonius: On Aristotle's On Interpretation 1–8, translated by D. Blank. London and Ithaca 1996. Ammonius: On Aristotle's On Interpretation 9, with Boethius: On Aristotle's On Interpretation 9, translated by D. Blank (Ammonius) and N. Kretzmann (Boethius). London and Ithaca 1998 John Philoponus: On Aristotle On Coming-to-be and Perishing 1.1–5, translated by C. J. F. Williams. London and Ithaca 1999 John Philoponus: On Aristotle On Coming-to-be and Perishing 1.6–2.4, translated by C. J. F. Williams. London and Ithaca 1999. John Philoponus: On Aristotle On the Soul 2.1–6, translated by W. Charlton. London and Ithaca 2005 John Philoponus: On Aristotle On the Soul 2.7–12, translated by W. Charlton. London and Ithaca 2005 John Philoponus: On Aristotle On the Soul 3.1–8, translated by W. Charlton. London and Ithaca 2000 John Philoponus: On Aristotle On the Intellect (de Anima 3.4–8), translated by W. Charlton. London and Ithaca 1991. Notes References Andron, Cosmin. "Ammonios of Alexandria",The Routledge Encyclopedia of Ancient Natural Scientists, eds. Georgia Irby-Massie and Paul T. Keyser, New York: Routledge, 2008.