Email: jeff.mcmahan@philosophy.ox.ac.uk

Personal Biography

My first degree was in English literature, after which I read PPE for two years at Corpus, then began the DPhil under the supervision first of Jonathan Glover and then of Derek Parfit.  I completed my PhD at Cambridge under the supervision of Bernard Williams.  Before returning to Oxford in 2014, I taught at the University of Illinois and at Rutgers University in New Jersey. I held the position of Sekyra and White's Professor of Moral Philosophy until October 2024.

Research 

I have written about a range of issues involving or related to harming, killing, and saving.  These issues include war, self- and other-defense, abortion, infanticide, euthanasia, the metaphysics of personal identity, the metaphysics of death, the evaluation of death, brain death, the moral status of animals, causing people to exist, obligations to future people, disability, torture, philanthropy, gun control, the distinction between doing harm and allowing harm to occur, and the distinction between harming as a means and harming as a side effect.  I am currently writing a book called The Ethics of Creating, Preserving, and Ending Lives (OUP), which is concerned with a range of issues in ‘population ethics’, such as whether a person can be harmed or benefited by being caused to exist, whether the expectation that a person would have a life worth living provides a moral reason to cause that person to exist, and whether it is wrong to cause a well-off person to exist if one could cause a different, better-off person to exist instead. These and related issues are, surprisingly, the source of some of the most intractable problems and paradoxes in moral theory. One of the aims of the book is to explain why understanding these issues is essential to understanding a range of practical ethical issues as diverse as abortion, prenatal injury, meat eating, climate change, war, reparations for historical injustice, and the threat of human extinction.

Representative Publications

The Ethics of Killing: Problems at the Margins of Life (Oxford University Press, 2002)

Killing in War (Oxford University Press, 2009)

“Cognitive Disability, Misfortune, and Justice,” Philosophy and Public Affairs 25 (1996): 3-34.

“Paradoxes of Abortion and Prenatal Injury,” Ethics 116 (July 2006): 625-55.

“Nonresponsible Killers,” Journal of Moral Philosophy 15 (2018): 651-682.

“Necessity and Proportionality in Morality and Law,” in Claus Kreß and Robert Lawless, eds., Necessity and Proportionality in International Peace and Security Law (New York: Oxford University Press, 2021).

“Climate Change, War, and the Non-Identity Problem,” Journal of Moral Philosophy  18 (2021): 211-238.

“Defence Against Parfit’s Torturers,” in McMahan et al., eds., Principles and Persons: The Legacy of Derek Parfit (Oxford: Oxford University Press, 2021).

“Creating People and Saving People,” in Gustaf Arrhenius, et al. eds., The Oxford Handbook of Population Ethics (Oxford University Press, 2022).

Most of my essays can be downloaded from my website:

https://www.philosophy.ox.ac.uk/people/jeff-mcmahan#tab-2391051