Contemporary atheism marches behind the banner of science. It is perhaps no surprise that several leading atheists—from biologist Richard Dawkins to cognitive psychologist Steven Pinker to physicist Victor Stenger—are also leading scientists. The central argument of these scientific atheists is that modern science has refuted traditional religious conceptions of a divine creator. But of late atheism seems to be losing its scientific confidence. One sign of this is the public advertisements that are appearing in billboards from London to Washington DC. Dawkins helped pay for a London campaign to put signs on city buses saying, “There’s probably no God. Now...