Paine's core argument against monarchy is simple: there is no rational basis for the claim that because a man was a good king, his son will be a good king. Hereditary succession confuses a political office with a piece of property. It is as if we proposed to fill the position of surgeon, or ship's captain, or head of any business enterprise by passing it automatically to the incumbent's eldest child. No one would accept this in any domain where actual competence was required. The reason we accept it in politics is custom, inertia, and the ideology of divine right — not reason. Examined by reason alone, it is manifestly absurd.
Paine traces the historical origin of monarchy in the Hebrew scriptures and finds it instructive. The Israelites demanded a king like other nations, and the prophet Samuel warned them what they were asking for: their sons would be taken for soldiers, their daughters for servants, their best fields for royal revenue, and they would cry out under the king's oppression. God granted their wish as a punishment for their faithlessness. This biblical argument — monarchy as fall from republican grace — was aimed squarely at Paine's audience of Protestant colonists, for whom scripture carried more authority than Locke or Montesquieu.
Beyond the theoretical argument, Paine marshals the historical record: how many wars have been started by kings pursuing personal glory? How much treasure has been spent on dynastic ambition? How often has a monarch's personal incapacity — madness, vice, incompetence, minority — produced political chaos? The record of hereditary government is, Paine argues, a record of continuous catastrophe punctuated by accidental periods of adequate rule when a competent monarch happened to be on the throne. Republican government, in which rulers are chosen for their merit and held accountable for their performance, has no need to rely on the lottery of birth.
Paine's critique of monarchy was not aimed only at the British crown but at the institution of hereditary rule as such — a point that became clearer when he later defended the French Revolution's abolition of the monarchy in Rights of Man. Common Sense is thus not merely a pro-independence pamphlet but the founding document of a consistent republican political philosophy.
