This paper examines Gustave de Beaumont’s often neglected political thought as expressed in his 1835 novel Marie, ou de l’esclavage aux États-Unis. Despite being most commonly seen as a sort of “addendum” to Alexis de Tocqueville’s thought, Marie entails original and stimulating social and political views. I argue that these views can be read as fragments of a consistent theoretical pattern, a dizygotic twin of Tocqueville’s better-known “liberalisme d’espece nouvelle”. In order to test this hypothesis I focus my analysis on three of Marie’s main themes: slavery, race, and political democracy. I argue that, through the novel’s narrative form, Beaumont both displays a keen analysis of slavery (rejecting its understanding as a negative condition – that is, as something flourishing within legal voids – and highlighting instead the deliberate political efforts which allow its perpetration) and a constructivist conception of race belonging. Nonetheless, by intertwining Pascal’s dualism between coeur and raison and Montesquieu’s dialectic between moeurs and lois, Beaumont proposes a distinctly conservative declination of the “tyranny of the majority” theory, suggesting that only a monarchic political power is strong enough to protect minorities from popular hate. As a whole, Marie’s liberalism seems at the same time more socially progressive and more politically conservative