Starting in the 1870s, American jurists deciding cases of trademark infringement began advancing arguments that the ordinary purchaser was an unwary one, easily deceived by imitations. Embedded within their legal decisions was a vision of the typical consumers' habitual behavior and cognitive ability. In response to legal critics who argued that the presumed psychology of the consumer was unevenly deployed, applied psychologists developed laboratory-based experiments and scales for determining the likelihood that the “average” purchaser would be confused. Although these psychologists failed in their goal of securing regular legal patronage, this commercial context and the resulting experiments were constitutive of the delineation of “recognition” as a distinct mental process. Furthermore, this case study complicates the scholarly consensus about the role of standardization and personal responsibility in the liberal administration of mass society. © 2007 Wiley Periodicals, Inc.