This is the the twenty-fifth post in my Theories of Knowledge and Reality series. Follow the link for more on the series and for links to other entries as they appear. In the last post, I looked at why some people think theism serves as the best non-naturalistic foundation for ethics. This post now looks at an objection to seeing God as the basis of morality.
In Plato's dialogue Euthyphro, he has the character of Socrates raise an objection to the idea that morality has something to do with the gods. If something is good just because the gods view it as good, the gods could command anything, and it would automatically be right. You don't have to be a polytheist for that consequence. How could God's mere choice be the basis of morality? Are good things good because God says they're good, or does God just declare them good based on seeing their goodness? If they are already good, then doesn't that mean God's choice didn't make them good?
Many theists are attracted to the thesis that God simply decides what is morally good. But that seems arbitrary. God could have declared murder to be good, and that would have made it good, on this view. Most theists don't want to say that once they consider it. Also, this view also doesn't explain why it's meaningful to praise God. If anything God does, no matter what it is, is automatically good, then why is it saying anything if we praise God for being good? Third, this view doesn't explain why God would say certain things are good and not others. If all that makes it good is the fact that God chose it, then God isn't choosing it for any reasons. Do we want to say that God acts without rationally compelling reasons? Do we want to say that there is no explanation at all for why God chose these things to be good? If we say that, then we really haven't explained morality at all, have we? If any choice at all would be good just because God says so, that leads to these unwelcome consequences. So it must be that what makes them good is not God's mere choice.
So maybe God just declares things to be right and wrong out of seeing that those truths are true in a way independent of God. If so, it seems to be an external limitation on God, who isn't supposed to have such limitations. Morality would give God obligations, and thus would be external to God. Many theists would be uncomfortable with that. Also, this doesn't allow the moral argument to get going to begin with, since the moral truths would have to be independent from God. God's nature doesn't explain them after all. This second option is not the way to go to defend the moral argument against the Euthyphro objection.
Most contemporary philosophers stop there and just conclude that God cannot be the basis of morality. The moral argument suddenly becomes a ridiculous non-starter in the eyes of most philosophers I know, pretty much entirely because of this objection. But anyone presenting the objection and stopping there betrays a severe ignorance of how this question was treated by one of the most well-known and influential of all theistic philosophers. Thomas Aquinas gives a response to Plato's objection that avoids both of the above problems, and unfortunately very few philosophers nowadays even seem to know about his response.
Aquinas' suggestion is to give a third option: God's perfect nature explains morality. If so, then moral truths aren't external to God after all, so there's no external limitation. Also, the moral argument isn't immediately defeated, since God’s nature does the explaining. Third, it's not as if God just chooses out of lots of options what is good or evil, so it's not arbitrary. Its foundation is God's nature, something essential to being a perfect being. Aquinas' view avoids the problems of the two options of the dilemma while still providing a foundation for morality. So it seems the Euthyphro objection does not undermine the conclusion of the moral argument.