Mark Twain is one of my favorite writers and for all intents and purposes, an atheist. He has numerous writings that detail some of his theological musings. This one is among my favorites.http://www.ratbags.com/rsoles/comment/twain02.htm
How often we are moved to admit the intelligence exhibited in both the designing and the execution of some of His works. Take the fly, for instance. The planning of the fly was an application of pure intelligence, morals not being concerned. Not one of us could have planned the fly, not one of us could have constructed him; and no one would have considered it wise to try, except under an assumed name. It is believed by some that the fly was introduced to meet a long-felt want. In the course of ages, for some reason or other, there have been millions of these persons, but out of this vast multitude there has not been one who has been willing to explain what the want was. At least satisfactorily. A few have explained that there was need of a creature to remove disease-breeding garbage; but these being then asked to explain what long-felt want the disease-breeding garbage was introduced to supply, they have not been willing to undertake the contract.
There is much inconsistency concerning the fly. In all the ages he has not had a friend, there has never been a person in the earth who could have been persuaded to intervene between him and extermination; yet billions of persons have excused the Hand that made him - and this without a blush. Would they have excused a Man in the same circumstances, a man positively known to have invented the fly?