 This historical overview of scientific debates over nativism reveals a few general patterns. One is that there has never been an agreed scientific definition of an “instinctive” or “innate” trait. During the late 19th century C.L. Morgan noted the proliferation of different definitions of instinct and criticized his contemporaries for their sloppy use of language. The same criticisms are echoed in the work of Dunlap, Bernard, and Kuo, who all complained that imprecision in the definition of “instinct” led researchers to draw faulty inferences. Lehrman and other critics of the ethological revival of instinct likewise complained that this concept lacked scientific precision.