Can we model politics as exclusively based on self-interest, leaving virtue aside? How much romance is there in the study of politics? We show that James Buchanan, a founder of public choice and constitutional political economy, reintroduces a modicum of romance into politics, despite claiming that his work is the study of "politics without romance." Buchanan's model needs an ethical attitude to defend rules against rent-seeking.
We claim that Adam Smith, more than David Hume, should be considered one of the primary intellectual influences on Buchanan's public choice and constitutional political economy. It is commonly believed that Hume assumes in politics every man ought to be considered a knave, making him an influence on Buchanan's idea of politics without romance. Yet, it is Smith who, like Buchanan, describes rent-seeking and suggests that public virtues may be the remedy through which good rules maintaining liberty and prosperity can be generated and enforced. Smith, like Buchanan, rejects sole reliance on economic incentives: the study of politics needs some romance.