Can we draw substantive conclusions about the reasons for action agents have from premisses about the desires of their idealized counterparts? The answer is that we can. The argument for this conclusion is Rawlsian in spirit, focusing on the choices that our idealized counterparts must make simply in virtue of being ideal, and inferring from these choices the contents of the desires that they must have. It turns out that our idealized counterparts must have desires in which we ourselves figure as both agents and patients, and in which others must figure too, though only as patients.