If one believes that God is an abstract and unknowable concept, then what alternatives are there for guiding a person or society's moral values?

Atheism and agnosticism are only two reasons not settle moral perplexity by trying to ascertain God's will (see below). Atheists and agnostics will try to find reflectively acceptable principles and rules to guide their actions. It makes sense to start with widely shared rules about nonmaleficence, beneficence, honesty, fidelity, and fair play. Different ethical systems justify and sometimes interpret these rules in different ways. Finding the right moral theory is a matter of finding an ethical system that interprets and justifies these rules in a reflectively acceptable way. In the meantime, most of us will try to regulate our affairs as best we can byapplying these secondary rules.

The interesting question is not so much how is morality possible independently of religion, but how is religion possible independently of morality. Even if we are theists, there's a strong case for thinking that morality is independent of religion. Socrates long ago asked whether something was right because God commanded it or whether God commanded it because it was right (the famous question asked in Plato's dialogue Euthyprho). Socrates reasoned that God's will could not make something valuable, because that would make his preferences arbitrary. Instead, Socrates concluded, the theist should say that God commands what he does, because he himself is good. On this view, God's commands are principled and track what is independently valuable. This also explains why thesists often feel compelled to resolve debates about what God has willed, and how we can ascertain his will, by appeal our moral ideas about what a morally good God could have willed.

But then there should be no deep puzzle about how there could be an objective morality without God, because plausible versions of theism must themselves recognize an objective morality -- that is, one independent of God's will.

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