Deliberative Contractualism and the Conditional Fallacy

Dr Nicholas Southwood (Australian National University)

Abstract: In a classic paper, Robert K. Shope famously argued that a range of counterfactualist theories in epistemology and ethics are vulnerable to what he called the ‘conditional fallacy’. Roughly, a counterfactualist theory T commits the conditional fallacy when the respects in which the relevant counterfactual circumstances differ from the actual world make T give the wrong verdict in the actual world. Given their counterfactual structure, it is natural to wonder whether counterfactualist versions of contractualism are also vulnerable to the conditional fallacy. Surprisingly, however, contractualists and their critics have not engaged much with this question directly. The one notable exception is Jussi Suikkanen. In a forthcoming paper, Suikkanen explicitly considers the question and argues that a number of counterfactualist versions of contractualism are guilty of committing the conditional fallacy. Among these he includes the ‘deliberative’ version of contractualism that I developed and defended in my book, Contractualism and the Foundations of Morality (OUP: 2010). My aim in this paper is to consider whether deliberative contractualism is indeed vulnerable to the conditional fallacy. To do this, I consider three versions on the conditional fallacy (Suikkanen’s version and two others). In each case, I suggest that, appropriately understood, deliberative contractualism doesn’t commit the conditional fallacy. This requires delving much deeper into the counterfactual structure of deliberative contractualism than I did in Contractualism and the Foundations of Morality. It also requires saying much more about e.g.: what it means to ‘agree to live by a principle’, the character and function of principles; and certain norms of deliberative rationality.