In this paper I explicate and defend the concept of a morally relevant harm. This concept figures prominently in common-sense and contractualist moral reasoning concerning cases where an agent can prevent harm to members of a large group or a small one, but not both. When the two harms to which members of these groups are exposed are morally relevant to one another, an agent is permitted (or perhaps required) to take into account the number of people he can save. When the harms are irrelevant, an agent should not even consider preventing the lesser harm, regardless of how many people will suffer it.

I argue for what I label the orbital conception of morally relevant harm, according to which harms that fall within the “orbit” of a given harm are relevant to it, while all other harms are not. In addition, I contend that the possibility of preventing a harm provides both a first-order reason to prevent that harm, and a second-order reason not to consider preventing irrelevant harms. I then demonstrate how this understanding of the concept of a morally relevant harm avoids two objections raised by Alastair Norcross: first, identifying a point along a continuous scale of harms at which the divide between relevant and irrelevant harms occurs, and second, the entailment that the mere possibility of being able to prevent harm that one is morally forbidden from preventing can determine which of two other actions morality requires.

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Post-print Article

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Copyright © 2008, Cambridge University Press. The definitive version is available at:

DOI: 10.1017/S0953820808003245

Full Citation: Lefkowitz, David. "On the Concept of a Morally Relevant Harm." Utilitas 20, no. 4 (December 2008): 409-23. doi:10.1017/S0953820808003245.