Rebutting the Theist Rebuttal

Theists often accuse atheists of being just as dogmatic in their beliefs as religious fundamentalists are in theirs. But Richard Dawkins, in his review of Christopher Hitchens' book God is not Great, makes the following argument:

The answer to the familiar accusation of atheist fundamentalism is plain enough. The onus is not on the atheist to demonstrate the non-existence of the invisible unicorn in the room, and we cannot be accused of undue confidence in our disbelief. The devout churchgoer recites the Nicene Creed weekly, enumerating a detailed and precise list of things he positively believes, with no more evidence than supports the unicorn. Now that’s overconfidence. By contrast, the atheist says the humble thing: of all the millions of possible entities that one might imagine, I believe only in those for which there is evidence – trombones, pelicans and electrons, say, but not unicorns or leprechauns, not Thor with his hammer, not Ganesh the elephant god, not the Holy Ghost.