Theists - What is your favorite quote from an atheist, whether it pertains to religion or not?

There's more to atheists than non-belief. Some of the most notable have written and said many other things regarding all the myriad facets of life. Look up a notable atheist or two on Wikiquote, and find something you agree with.

Oh, and pantheists, deists, and agnostics count as well.
Update: Bastion - My avatar is of the late great Sigmund Freud, who is the source of one of my personal favorite quotes: "Sometimes, a cigar is just a cigar." Always helps to remind me to simplify, and make everything easier.
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