Euthyphro dilemma

The Euthyphro dilemma is found in Plato's dialogue Euthyphro, in which Socrates asks Euthyphro, "Is the pious () loved by the gods because it is pious, or is it pious because it is loved by the gods?" (10a)

The dilemma has had a major effect on the philosophical theism of the monotheistic religions, but in a modified form: "Is what is morally good commanded by God because it is morally good, or is it morally good because it is commanded by God?" Ever since Plato's original discussion, this question has presented a problem for some theists, though others have thought it a false dilemma, and it continues to be an object of theological and philosophical discussion today.

Socrates and Euthyphro discuss the nature of piety in Plato's Euthyphro. Euthyphro proposes (6e) that the pious () is the same thing as that which is loved by the gods (), but Socrates finds a problem with this proposal: the gods may disagree among themselves (7e). Euthyphro then revises his definition, so that piety is only that which is loved by all of the gods unanimously (9e).

At this point the dilemma surfaces. Socrates asks whether the gods love the pious because it is the pious, or whether the pious is pious only because it is loved by the gods (10a). Socrates and Euthyphro both contemplate the first option: surely the gods love the pious because it is the pious. But this means, Socrates argues, that we are forced to reject the second option: the fact that the gods love something cannot explain why the pious is the pious (10d). Socrates points out that if both options were true, they together would yield a vicious circle, with the gods loving the pious because it is the pious, and the pious being the pious because the gods love it. And this in turn means, Socrates argues, that the pious is not the same as the god-beloved, for what makes the pious the pious is not what makes the god-beloved the god-beloved. After all, what makes the god-beloved the god-beloved is the fact that the gods love it, whereas what makes the pious the pious is something else (9d-11a). Thus Euthyphro's theory does not give us the very nature of the pious, but at most a quality of the pious (11ab).

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