Does morality need God? The classic dilemma is expressed by Socrates in Plato’s Euthyphro. Is something good because God commands it, or does God command it because it is good?

When you first read this you might wonder what the fuss is all about. But what the dilemma is setting is a kind of trap. If we say something is good because God commands it, what happens if God commands us to do what he told Joshua to do (Joshua 1-8): go and wipe out every living thing in the city of Jericho: men, women, children, cattle, donkeys, pet dogs, everything?

And (taking the other horn of the dilemma), if God commands it because it is good, then why do we need God to work out what is moral, because goodness is clearly something independent of God, which we can work out using (for example) our reason alone?

There are people who still believe in the divine command theory of ethics, which roughly speaking means that something is good because God commands it. They tend to be people, like evangelical Christians, who take the authority of the Bible seriously, or philosophers, like Robert Adams (a modern divine command theorist) who don’t think Euthyphro’s dilemma is fatal to their position. So how do we escape it?

One way is to argue that the dilemma sets up a false contrast. This is an either/or position which closes off further options (a classic false move in the logic of arguments: the world is either flat or square, it’s not flat, so it must be square! Actually it’s round, but you haven’t left me with that option!).

So suppose we argue that morality depends on divine revelation, rather than command, and specify the character of God as the key, rather than what he is supposed to say. We could use this (a sort of virtue ethics way out), for example, by taking a key verse of epiphany or revelation like Exodus 34 verse 6. God appears to Moses and reveals first his name (a rather strange name, as it happens, as Yahweh means “I am who I am” or “I will be who I will be”) and then his character, “I am the Lord, overflowing with steadfast love and faithfulness” and other key characteristics: compassion, mercy, and (interestingly, for the Joshua example) jealousy, as God will not tolerate false gods leading people astray, or those, like the golden calf, which we construct for ourselves.

Leaving the problem of God’s anger and jealousy to one side, we might argue then that anything which violates the virtue of love or steadfast loyalty is wrong, and anything in line with God’s compassion and mercy is right. We might then say that abhorrent commands (such as go and commit genocide) must be rejected as violating the primary characteristics of love and mercy, and that Joshua has made some kind of mistake.

Of course, we could also take the other prong of the dilemma and say; we don’t need God at all. We could be a natural law atheist appealing to what we can observe about the natural tendencies of human beings, a Kantian appealing to a priori reasoning, or a utilitarian arguing from some empirical, measurable good (such as the balance of happiness over misery). You can be a naturalist and an objectivist (Mill), a naturalist, objectivist and absolutist (Kant) or a naturalist and intuitionist (Ross) or various combinations between (you can have fun working out what they are as you study different moral philosophies).

What is clearly unacceptable is to argue, as Ivan Karamazov did in Dostoyevsky’s novel bearing his name, that “if God doesn’t exist, everything is permissible”. This is to insult the heroic atheist and denigrate human reason, as well as to deny the possibility of universal values. It is to make another logically invalid move, that of reductionism: to reduce morality to godlikeness, which itself depends on the picture of God we have in our minds.

Moreover, the sheer variety of gods on offer suggests that we need some way of arbitrating between them and avoiding the sort of arrogance that says: “what I believe must always be right”. This belief closes off conversation and rational debate, and encourages bigotry, judgmentalism and even (in history) murder and war.

Take reason away and we can’t do ethics at all.