Philosophical Studies

, Volume 175, Issue 4, pp 859–883 | Cite as

In dubious battle: uncertainty and the ethics of killing

  • Seth LazarEmail author


How should deontologists concerned with the ethics of killing apply their moral theory when we don’t know all the facts relevant to the permissibility of our action? Though the stakes couldn’t be higher, and uncertainty is endemic where killing is concerned, few deontologists have an answer to this question. In this paper I canvass two possibilities: that we should apply a threshold standard, equivalent to the ‘beyond a reasonable doubt’ standard applied for criminal punishment; and that we should fit our deontological ethical theory into the apparatus of decision theory. I show that the first approach faces insurmountable obstacles, while the second holds much more promise for deontologists than they (and their critics) might first have assumed.


Self-defence Uncertainty Deontological ethics Normative ethics Killing Harm Liability Decision theory 



This paper was inspired by discussions with Kim Ferzan, Jeff McMahan, Mike Otsuka, Jon Quong and Alec Walen in Princeton in 2013. Thanks to each of them, and to the Centre for Human Values, at Princeton, for hosting us. Since writing it up I have presented versions at: the Wallenberg Foundation’s Stockholm Centre for the Ethics of War and Peace conference in May 2014; the ANU’s Departmental Seminar; the University of Toronto Philosophy Departmental Seminar; and the Program in Ethics and Public Affairs Seminar at Princeton (all also in 2014). Thanks to Helen Frowe, Hanti Lin, Andrew Sepielli, Charles Beitz, and the audiences at these talks for their comments. For particularly helpful discussions, and for reading drafts of the paper, thanks to Christian Barry, Ed Elliot, Johann Frick, Anne Gelling, Alan Hájek, Adil Haque, Tom Hurka, Frank Jackson, Melissa Lane, Leon Leontyev, Jeff McMahan, Philip Pettit, Jon Quong, Andreas Schmidt, Wolfgang Schwartz, Annie Stilz, Brian Talbot, Sergio Tenenbaum, and Bas van der Vossen. Work on this paper was supported by Australian Research Council DECRA Grant DE130100811 and Discovery Grant DP170101394.


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© Springer Science+Business Media Dordrecht 2017

Authors and Affiliations

  1. 1.School of PhilosophyAustralian National UniversityCanberraAustralia

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