Three Ambiguities in the Knobe Effect

Volume 15
Issue 1
John Michael McGuire
The Knobe effect is widely regarded as one of the first and most important findings in the field of experimental philosophy. A good deal of research in this field over the past decade has been concerned with explaining the Knobe effect. However, much of this research has been vitiated by neglect for the more fundamental matter of defining “the Knobe effect.” In this article I address the definitional question and argue that the Knobe effect is in fact plagued by three ambiguities which have received insufficient attention. In the first place, I show that the term has both a narrow and a broad interpretation. In its narrow sense, the term refers to an effect that moral considerations allegedly have on ascriptions of intentional action; in its broad sense, it refers to an effect that evaluative considerations allegedly have on all folk psychological ascriptions. Secondly, I show that the narrow reading of “the Knobe effect” is itself ambiguous between one interpretation on which the moral considerations in question refer to conscious moral judgments and another interpretation on which they refer to non-conscious reactions to norm violations. Thirdly, I argue that the Knobe effect can be interpreted either as a hypothesis concerning how people ordinarily use certain folk psychological concepts or as a hypothesis concerning how people use those concepts only in the context of hypothetical thought-experiments. While the vast majority of researchers have assumed the former view, recent experimental research supports the latter view, suggesting that the Knobe effect is in fact an experimental artifact.

Key words: Joshua Knobe, the Knobe ef fect, the side-ef fect ef fect, intentional action, folk-psychological ascriptions