This essay considers Charles Brockden Brown’s Ormond as an imaginative experiment with neurodiversity, considering, in particular, what it means to know, as we do now, that different brains are fundamentally, neurologically different and how neurological difference might have been narrated before there was a language for it. This is an investigation not of intelligence or mental health but of fundamental neurological difference and what it might have meant for the late eighteenth century United States, then a new nation politically organized through republicanism in which representative (white, propertied) men were expected to represent the needs of “the people” and trusted with governance. Ormond troubles the foundational formulation that American bodyminds simply required the right education and training to become, in Benjamin Rush’s words, “republican machines” able “to perform their parts properly, in the great machine of the government of the state.” If republicanism was structured by a presumption of neurotypicality, Ormond presents a fascinating example of a novel working to represent different bodyminds during a time when there were not yet adequate narrative means for doing so.