A closer look at moral dilemmas: Latent dimensions of morality and the difference between trolley and footbridge dilemmas

Although a distinction between moral-personal and moral-impersonal dilemmas (Greene, Sommerville, Nystrom, Darley, & Cohen, 2001 Greene, J. D., Sommerville, R. B., Nystrom, L. E., Darley, J. M. and Cohen, J. D. 2001. An fMRI investigation of emotional engagement in moral judgement. Science, 293: 2105–2108. doi:10.1126/science.1062872.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) has been widely accepted as an explanation for a difference between the trolley and footbridge dilemmas (Thomson, 1985 Thomson, J. J. 1985. “The trolley problem”. In Ethics: Problems and principles, Edited by: Fischer, J. M. and Ravizza, M. Fort Worth, TX: Harcourt Brace Jovanovich.  [Google Scholar]), its psychometric properties remain a mystery. In this study 219 participants completed 62 moral dilemma tasks used in Greene et al. (2001 Greene, J. D., Sommerville, R. B., Nystrom, L. E., Darley, J. M. and Cohen, J. D. 2001. An fMRI investigation of emotional engagement in moral judgement. Science, 293: 2105–2108. doi:10.1126/science.1062872.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]), and the correlation structure among the dilemmas was analysed through factor analysis and structural equation modelling. Findings suggest that, first, moral-personal dilemmas are composed of one factor, indicating that the assumption in Greene et al. (2001 Greene, J. D., Sommerville, R. B., Nystrom, L. E., Darley, J. M. and Cohen, J. D. 2001. An fMRI investigation of emotional engagement in moral judgement. Science, 293: 2105–2108. doi:10.1126/science.1062872.[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) was supported. Second, moral-impersonal dilemmas are explained by two factors that reflect procedural and consequential aspects of decision making. Third, the trolley and footbridge dilemmas fall under the same factor category; therefore the difference between the two dilemmas cannot be attributed to emotional involvement. Additionally, the results of the structural equation modelling suggest that they differ in the engagement of rational processing.