I agree that it sound as though Twain cribbed from Paine, though I can't pull the exact quote. It seemed odd and interesting that the edition Wes was using had been edited by Moncure Daniel Conway. Is this the same Moncure Conway who served as SLC's British representative in th 1870's and beyond? His son? Was SLC's friend Conway an expert on Paine? Seems Wes might have tumbled to the genesis of SLC's anti-religious rhetoric, and simultaneously to how the ideas got to SLC in the first place.