Stephen Morse on the Fundamental Psycho-Legal Error

Stephen Morse has long proclaimed there to be a “fundamental psycho-legal error” (FPLE) that is regularly made by legal and social/psychological/medical science academics alike. This is the error of thinking that causation of human choice by factors themselves outside the chooser’s control excuses that chooser from moral responsibility. In this paper, I examine Morse’s self-labelled “internalist” defense of his thesis that this is indeed an error, and finds such internalist defense incomplete; needed is the kind of externalist defense of Morse’s thesis that can only be provided by a worked-out compatibilist moral philosophy. The body of the paper outlines the kinds of compatibilisms that are plausible, contrasting them with two less plausible attempts to salvage responsibility in the face of an advancing neuroscientific determinism. These two less plausible rescue attempts, libertarianism and fictionalism, each seek to salvage responsibility even while not disavowing the FPLE.