"A Most Astonishing Genius for Calculations": Arithmetical Prodigies, the Science of the Mind, and Human Difference in the Early Republic

Abstract

In the early republic, two socially marginal, illiterate, and innumerate prodigies capable of astounding feats of mental arithmetic captivated audiences on both sides of the Atlantic: Thomas Fuller, an enslaved Virginian, and Zerah Colburn, the eight-year-old son of a poor Vermont farm family. To account for the remarkable performances of such humbly situated prodigies, learned observers like Benjamin Rush and Dugald Stewart mobilized the contemporary science of the ostensibly universal human mind to construct and legitimize hierarchies of human difference, most explicitly race, less obviously class. The prodigies' unfamiliarity with letters and numerals raised a fundamental question: how did they do it, or in the context of the reigning model of the mind, which faculty enabled them to do it? In reply, men of learning passed over the exalted faculties of reasoning and imagination to the appropriately humble faculty of memory. That choice made sense in light of how most people learned and applied arithmetic. Given that computational skill in this era functioned alongside literary, artistic, and scientific achievement as the mark of a group's potential for genius, it also averted the attribution of genius to Fuller and Colburn by establishing a congruence between a rank-ordered ladder of faculties and a hierarchy of human groups. In the riddle of the calculating prodigies, Enlightenment thinkers thus established an intellectual grounding for an explicitly racial science of the human body by covertly ranking the "universal" human mind.