It is often assumed that current disability constructs exist in conceptual isolation from one another. This article explores the tangled historical relationship between "mental retardation" and learning disability in the writings and speeches of special education pioneer Samuel A. Kirk. Beginning in the 1950s, Kirk repeatedly told an educability narrative that described children with low IQ scores as capable students worthy of instruction. However, when he tried to clearly distinguish between the new learning disability construct and the older mental retardation, Kirk altered his standard tale. True intellectual potential then shifted to the learning disability, leaving mental retardation doubly stigmatized as the disorder of educational infertility.