Karen Margrethe Nielsen

Fellow & Tutor in Philosophy; Associate Professor in Philosophy

I am an Associate Professor in the Faculty of Philosophy and a Tutorial Fellow of Somerville College, Oxford.

My research has centred on questions at the intersection of Aristotle’s ethics and moral psychology, and especially Aristotle’s theory of decision (prohairesis). I have published on the reception history of the Nicomachean Ethics and on Aristotle’s reproductive biology.

Last spring, CUP published a volume of papers I edited with Devin Henry, Bridging the Gap between Aristotle’s Science and Ethics (2015). The book consolidates emerging research on Aristotle’s science and ethics in order to explore the extent to which the concepts, methods, and practices he developed for scientific inquiry and explanation are used to investigate moral phenomena.

I received my PhD from the Sage School of Philosophy at Cornell University, where I wrote a dissertation titled “Aristotle’s Theory of Decision (prohairesis)” under the supervision of Terry Irwin (2006). My first academic appointment after Cornell was in Canada. I came to Western University as an Assistant Professor in the fall of 2005, and was tenured and promoted to Associate Professor in July 2012. I spent the 2012-13 academic year on sabbatical leave in Oxford, where I was Visiting Scholar at Corpus Christi College in Michaelmas term. I have also taught at St. Catherine’s College, Oxford. In the 2007/8 academic year, I held a Lectureship in the Faculty of Philosophy at Cambridge University and a Temporary Lectureship at Trinity College, Cambridge. Before arriving at Cornell on a Fulbright Fellowship in 2000, I was a lecturer in the Department of Philosophy at the Norwegian University of Science and Technology in my native city Trondheim, where I earned Cand. mag. (B.A.-equivalent) and Cand. philol. (M.A.- equivalent) degrees in the late 90’s.

A note on my name: I sign with both my first names (“Karen Margrethe”), and prefer that all three names appear in writing. Oxford email doesn’t recognise Scandinavian naming practices, so my email address leaves out my second first name. If you find the cluster of consonants in “Margrethe” hard to pronounce, I’m fine with “Karen”!

I have lectured on a wide range of topics in Ancient Philosophy over the past ten years; in Oxford, I have given lectures on Aristotle’s Ethics and Latin Philosophy (specifically, Cicero’s De Finibus), and I have also given graduate seminars on Aristotle’s Three Ethics with Prof. Terry Irwin. I tutor students for a number of papers, including Plato’s Republic (Greek and translation); Aristotle’s Nicomachean Ethics (Greek and translation); Aristotle’s Physics; Sextus Empiricus’ Outlines of Pyrrhonism; Ethics; Latin Philosophy; Plato’s Euthyphro & Meno; Early Greek Philosophy; Early Modern Philosophy; Moral Philosophy; and General Philosophy.

I have served as Graduate Officer for Women in the Faculty of Philosophy from 2013-2016, as well as on a range of committees in the Faculty and at Somerville College.


Bridging the Gap Between Aristotle’s Science and Ethics, D. Henry and K. M. Nielsen (eds.) (Cambridge University Press, 2015)

“The Definitions of Phronêsis and Euboulia in Nicomachean Ethics VI”, in Carlo Natali and Pierre-Marie Morel (eds.), ‘Definitions in Aristotle’s Practical Philosophy’, special issue of Revue de Philosophie Ancienne. Forthcoming 2020

“The Tyrant’s Vice: Pleonexia and Lawlessness in Plato’s Republic”, Philosophical Perspectives 33, 2019, pp. 146-169

“Why Self-Knowledge Matters for Virtue”, in Fiona Leigh (ed.), Self-Knowledge in Ancient Philosophy, volume based on 2009 Keeling Colloquium (Oxford: Oxford University Press, 2020), pp. 45-70

“Deliberation and Decision in the Magna Moralia and Eudemian Ethics”, in Brink, Sauvé-Meyer & Shields (eds.), Virtue, Happiness and Knowledge: Essays for Gail Fine and Terence Irwin (Oxford: Oxford University Press, 2018), pp. 197-215

“Spicy Food as Cause of Death: Coincidence and Necessity in Metaphysics E 2-3”, Oxford Studies in Ancient Philosophy vol. 52 (2017), pp. 303-42

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