Ima Utilitarian uses a consistency argument against egoism.
Ima Utilitarian uses a consistency argument against egoism.
Egoism says "Everyone ought to do whatever maximizes their own self-interest, regardless of how this affects others." To hold this consistently, we'd have to want other people to live that way toward us. So we'd have to desire that X harm us greatly (even paralyze us for life) if this would maximize X's self-interest. But we can't desire this. So we can't consistently accept the principle.
So egoism, even though it may remain a temptation, can't be accepted as a rational view about how we ought to live.
Ima Utilitarian uses a consistency argument against egoism.
Egoism says "Everyone ought to do whatever maximizes their own self-interest, regardless of how this affects others." To hold this consistently, we'd have to want other people to live that way toward us. So we'd have to desire that X harm us greatly (even paralyze us for life) if this would maximize X's self-interest. But we can't desire this. So we can't consistently accept the principle.
So egoism, even though it may remain a temptation, can't be accepted as a rational view about how we ought to live.