Defeating Egoism

I think Adams is right that egoists fail in arguing against an ideal involving human benevolence. But I think the argument that engagement with one's own good will be impoverished without altruistic motivation only shows that altruism is at least an instrumental good (on 75-76). If Adams has not already convinced us that there is intrinsic value in altruism by the part where he brings up the objection from egoism, then this is not an interesting reply. If he has convinced us of the intrinsic value in altruism, then the egoist would pose no threat. It is already a common sense view that sometimes acting altruistically helps us, and overall this is not what Adams is trying to establish. So I think Adams could do better in defeating the egoist.