Explaining the Knobe Effect

Abstract

Joshua Knobe famously conducted several case studies in which he confronted survey subjects with a chairman who decides to start a new program in order to increase profits and by doing so brings about certain foreseen side effects. Depending on what the side effect is in the respective case, either harming or helping the environment, people gave asymmetric answers to the question as to whether or not the chairman brought about the side effect intentionally. Eighty-two percent of those subjects confronted with the harm scenario judged the chairman to have harmed the environment intentionally, but only 23 percent of the subjects confronted with the help scenario judged the chairman to have helped the environment intentionally (Knobe, 2003). This at first sight surprising asymmetry is called the ‘Knobe effect’, and together with the explanation Knobe provided for his findings it gave rise to a great amount of responses in the literature. Many follow-up studies were conducted that were meant either to confirm or to reject the Knobe effect, and many comments were written on how to interpret the data correctly. Most of these very different responses share the view that the asymmetry is surprising and has to be explained: the chairman went through the same reasoning and decision process, both side effects are equally foreseen by the chairman, his motivation (which is making profit) is both times the very same, and there is no external influence that could explain why people judge his harming the environment to be brought about intentionally, but helping the environment not to be.