EXPERIMENTAL MORAL PSYCHOLOGY AND ITS NORMATIVE IMPLICATIONS

This thesis explores the relationships between experimental moral psychology and normative ethics. It specifically examines neuromoral theories, according to which a deeper understanding of the machinery for moral judgments could lead humans to make better moral judgments. In this thesis I use the widely discussed neuromoral theory by Joshua Greene as a case study. I first examine Greene’s descriptive claims in experimental moral psychology (Ch. 2). Then I review descriptive hypotheses concerning human moral cognition that are alternative to Greene’s and I conclude that the data available so far are not sufficient to rule all alternatives out. Theories in experimental moral psychology are presently underdetermined by the data. In Ch. 4 I critically delve into Greene’s neuromoral theory, highlighting its problematic points. Greene derives normative consequences from empirical results through the Argument from Morally Irrelevant Factors. This argument is not persuasive because it is not backed by an analysis of judgments about moral relevance of factors, such as “Spatial distance is a moral irrelevant factor”, which are key premises in Greene’s argument. I argue that these judgments cannot be taken for granted because they are often deeply controversial. Greene also falls in a recurring problem, i.e. the so-called ‘meta-normativity problem’. It is not clear what kind of normativity neuromoral theorists are referring to when they say that empirical science could help humans make better moral judgments. These shortcomings make Greene’s neuromoral theory unconvincing. However, Greene’s descriptive work has greatly contributed to further the understanding of the machinery for moral judgments.