Last week I mentioned three philosophical arguments that concern very different subjects (and have very different advocates) but that have this in common: their critics think them tautological. Under the prodding of a commenter, I'd like to be more specific about one of them today. Some people argue that belief in God is necessary, and thus that God's existence must be postulated even if His existence cannot be proven, because He serves as the foundation of moral behavior. Let us call this argument FFM (faith for morals). The critics say this is tautological. Does God tell us not to commit adultery because it is a bad thing, or is it bad because He tells us not to do it? According to the critics of FFM, the FFM argument must say "both." Thus, it falls into circularity and tautology. Now particular advocates of FFM might well have expressed themselves in ways that sound like this. But that isn't a very interesting inquiry. A much more important inquiry ...