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In “Killing in Self-Defense” (119 Ethics 507 (2009)), Jonathan Quong claims that one may kill innocent aggressors and threats in self-defense, but he denies that it follows from his position that innocent bystanders may also be killed when one acts defensively. Quong argues that defenders have an agent-relative permission to favor their own lives over others’. However, there are moral constraints, including that one may not “use someone as a mere means,” and Quong claims that it is this constraint that prohibits the killing of innocent bystanders. To reach this conclusion, Quong construes the “means principle” quite broadly to include not only the using of a person but also the using of that person's space. Quong therefore maintains that it is impermissible to shove a bystander out of an alcove so that you can squeeze into it, causing a runaway trolley to hit him instead of you, because you are using the bystander as a mere means when you use his space in the alcove. This response raises a number of concerns with Quong’s argument. First, Quong overstates the relationship between an individual’s agency and the space he occupies. Second, and relatedly, Quong misconstrues the means principle – using an individual’s space is not using him. Third, there is an inherent tension between an agent-relative permission that looks to what morality can fairly ask of someone and the means principle’s constraint on behavior. That is, a person of reasonable firmness may yield to using others or their property now and then. Finally, this essay questions whether Quong’s claim can be cabined in a way that complies with our deep-seated moral commitments in other cases.


self-defense, means principle, Quong

Publication Title

Ohio State Journal of Criminal Law

Publication Citation

8 Ohio St. J. Crim. L. 503 (2011)