Photo of D. Gregory MacIsaac

D. Gregory MacIsaac

Associate Professor; Bachelor of Humanities

Degrees:B.A. (University of King's College/Dalhousie), M.A., Ph.D. (Notre Dame)
Phone:613-520-2600 x 1803
Office:2A40 Paterson Hall.
Office Hours: Thursday 1:00-2:30
Website:Academic Home Page


D. Gregory MacIsaac is Associate Professor of Humanities at Carleton University. He has taught in the B.Hum program since 1998.  He grew up in Antigonish County, Nova Scotia, entering the Foundation Year Programme at the University of King’s College – Dalhousie (Halifax) in 1988. He took his B.A. degree in 1992 from the Dalhousie Department of Classics, in Ancient Languages and Ancient and Mediaeval Philosophy, and his M.A. (1994) and Ph.D. (2001) at the Department of Philosophy, University of Notre Dame (Indiana). He spent the academic year 1994-95 visiting the Hoger Instituut voor Wijsbegeerte (Higher Institute of Philosophy) at the Katholieke Universiteit Leuven, Belgium, studying Neoplatonism and Contemporary Continental Philosophy. In 2005-06 he was a Chercheur Étranger at the École Pratique des Hautes Études and C.N.R.S., Paris, and in 2011-12 he was a visiting research at the Plato Centre, Trinity College Dublin, and at the Institute of Classical Studies, University of London.

In the Bachelor of Humanities, Professor MacIsaac’s main duty is HUMS 2000, the second-year Core-Humanities Seminar, Reason and Revelation. This is an intensive course on Ancient and Medieval Philosophy, covering authors from Plato to Dante. Professor MacIsaac has also taught HUMS 3205, Platonism and Idealism, and a number of fourth-year Research Seminars on topics such as Plato, Aristotle, Plotinus, Eriugena, Hegel, and Heidegger. Prof. MacIsaac currently teaches HUMS 1200, Humanities and Classical Civilization, the required first-year Humanities writing course, and co-ordinates HUMS 1500, Five Books that Changed the World, a Great-Books course for non-Humanities students.

Prof. MacIsaac is an award-winning teacher. At Carleton he has won:

  • Provost’s Teaching Fellowship
  • Teaching With Technology Award
  • Faculty of Arts and Social Sciences Teaching Award
  • Teaching Achievement Award

Research Interests

  • Neoplatonism, especially Proclus and Neoplatonic epistemology
  • Plato and the history of Platonism
  • German Idealism, Contemporary Continental Philosophy
  • Dante, philosophical literature

2018-2019  Courses

HUMS 2000 Reason and Revelation (F/W)

HUMS 1200A Humanities and Classical Civilisation (F)

HUMS 3500 Ancient and Medieval Intellectual History (W)


Geometrical First Principles in Proclus’ Commentary on the First Book of Euclid’s Elements,” Phronesis 59 (2014) pp.44-98.

Non enim ab hiis que sensus est iudicare sensum. Sensation and Thought in Theaetetus, Plotinus and Proclus,” International Journal of the Platonic Tradition 8 (2014) pp.192-230.

Philosophy as the Exegesis of ‘Sacred’ Texts,” in Philosophy and the Abrahamic Religions: Scriptural Hermeneutics and Epistemology, ed. T. Kirby, R. Acar and B. Bas (Cambridge Scholars Publishing, 2013) pp.95-134.

The Nous of the Partial Soul in Proclus’ Commentary on the First Alcibiades of Plato,” Dionysius 29 (2011) pp.29-60.

Νόησις, Dialectique et Mathématiques dans le Commentaire aux Éléments d’Euclide de Proclus,” in Études sur le Commentaire de Proclus au premier livre des Éléments d’Euclide, ed. A. Lernould (Presses Universitaires du Septentrion, 2010) pp.125-138.

Platonic Deconstruction:  A Review-article of Neoplatonism after Derrida.  Parallelograms.  By Stephen Gersh,” Dionysius, 27 (2009) pp.199-232.

The Soul and the Virtues in Proclus’ Commentary on the Republic of Plato,” Philosophie Antique, 9 (2009) pp.115-143.

The origin of determination in the Neoplatonism of Proclus,” in  Divine Creation in Ancient, Medieval, and Early Modern Thought.  Essays presented to the Rev’d Doctor Robert D. Crouse , ed. Willemien Otten, Walter Hannam, Michael Treschow (Leiden: E.J. Brill, 2007) pp.141-172.

Neoplatonism and the Hegelianism of James Doull,” Animus, 10 (2005) pp. 30-43.  Online philosophy journal, Memorial University of Newfoundland.

Projection and Time in Proclus,” in Medieval Philosophy and the Classical Tradition in Islam , Judaism, and Christianity, ed. John Inglis (London: Curzon Press, 2002) pp.83-105.

Phantasia between Soul and Body in Proclus,” Dionysius , 19 (2001) pp.125-136.

The Final Section of Proclus’ Commentary on the Parmenides: A Greek retroversion of the Latin translation, by Carlos STEEL and Friedrich RUMBACH, with an English translation by D.Gregory MACISAAC,” Documenti e studi sulla tradizione filosofica medievale (Brepols, 1997) pp.211-267.

Work in Progress:

Politeia: An Introduction to the Study of Plato’s Republic. This is an extended commentary on the argument of the Republic .

Plato’s Metaphysical Dialogues. This is an extended commentary on a number of so-called Later Dialogues, including TheaetetusParmenidesSophist, and Statesman.