The Second Mistake in Moral Mathematics is Not About the Worth of Mere Participation
"The Second Mistake" (TSM) is to think that if an act is right or wrong because of its effects, the only relevant effects are the effects of this particular act. This is not (as some think) a truism, since "the effects of this particular act" and "its effects" need not co-refer. Derek Parfit's rejection of TSM is based mainly on intuitions concerning sets of acts that over-determine certain harms.
