Effect is sure, but explanation is unsure: Closer investigation of the foreign language effect with Japanese participants

The foreign language effect (Costa et al., 2014) refers to a phenomenon in which the response to a moral dilemma depends on whether it is asked in a native or second language. This study explored this effect with Japanese participants using various types of moral dilemmas. Study 1 adopted twelve variations of trolley dilemmas from Mikhail (2007). Study 2 used seven types of moral dilemmas from Greene et al. (2001). The dilemmas required permissibility and understandability judgments. Results of the two studies demonstrated the following two points. (1) Interactions between types of dilemmas (switch/footbridge) and language (native/foreign) were significant in both studies, indicating that the foreign language effects were replicated consistent with Costa et al. (2014). (2) Evidence that contradicts the theoretical explanation of the foreign language effect was also found.