Paine's argument throughout Common Sense relies heavily upon a logical fallacy: he consistently appeals to God as the definitive moral authority. In making this appeal to authority a core part of his argument, Paine assumes that his readership is composed entirely of Christians; for any person who is not a Christian, however, the argument would immediately fall to pieces. Take this passage, for instance, wherein Paine references a Bible passage condemning monarchy:
When a man seriously reflects on the idolatrous homage which is paid to the persons of Kings, he need not wonder, that the Almighty ever jealous of his honor, should disapprove of a form of government which so impiously invades the prerogative of heaven. Monarchy is ranked in scripture as one of the sins of the Jews, for which a curse in reserve is denounced against them. The history of that transaction is worth attending to.
Though Paine might have been warranted, at the time of his writing this, in assuming that most of his readership were Christians, the appeal to authority in this passage represents a fallacy nonetheless. If a person does not believe in sin as a concept, the language condemning monarchy as such would have no effect.
Paine's appeal to divine authority, while a fallacy, also represents the crux of his moral argument: his ethos, or means of establishing credibility with his audience as he argues against the monarchy, hinges on his ability to refer to a moral authority higher than himself or any other earthly being.
