Socrates and Euthyphro agreed that there are many types of acts that are considered to be pious. Socrates claimed that this commonality had to be accounted for by some basis for unity. There must be something "the same and alike in every [pious] action." He called this unifying factor a "form" or "appearance." The form plays the special role as that which "makes all pious acts pious." It is pretty clear from the rest of the dialogue that Socrates sought the form of piety in the justice or goodness of an action. But for now, it is sufficient to say that an account of what piety is must reveal this form. And Euthyphro never manages to do this.
