Not sure I follow Brendan. I know people who say "Because of my belief in the free-market etc etc we should..." or "because I believe the free-market need to be managed etc etc we need to..." or "I believe Jesus/Allah/whoever would want me/us to...." But I've not heard "my atheist belief dictates that we should...." Saying something doesn't exist doesn't mean it doesn't. But until it's shown to exist, then, as with my bovril tin, not believing it is surely the only sensible choice. But not believing in it doesn't inform any moral opinions