Euthyphro dilemma
Etymology
From Plato’s dialogue “Euthyphro” (c. 399 BCE), in which Socrates asks whether the pious is loved by the gods because it is pious, or pious because it is loved. “Dilemma” is Greek for “two premises.” Either horn is awkward for divine-command ethics: one makes goodness arbitrary, the other makes it independent of the gods.
noun phrase · /YOO-thi-froh dih-LEM-uh/
The question of whether something is good because a god commands it, or a god commands it because it is already good.
What it names
A fork that challenges any attempt to ground morality purely in divine authority.
Example
A student pressing whether murder is wrong simply because God forbids it, or forbidden because it is wrong, has stumbled onto the Euthyphro dilemma.
Related idea
The Euthyphro dilemma probes the source of moral authority; the is–ought problem raises a different gap, asking how any set of facts can justify a claim about what we ought to do.