 Perhaps the real challenge that the Euthyphro poses concerns the normative authority of the responses of any kind of subject defined in non-evaluative terms. One way to develop this challenge may be called the Missing Normativity Problem. Many believe that moral rightness or wrongness are categorically reason-giving features of actions. Everyone, regardless of their interests and desires, has a reason to refrain from morally wrong behaviour. Suppose, then, that to be wrong is to be such as to be disapproved of by any ideal observer. On a reductivist view, this is a natural property of the action, specified in non-normative terms. The challenge is: why would such a natural property be categorically reason-giving? Why should people care about doing only things that would not be disapproved of by a hypothetical spectator?