ABSTRACT
The dichotomy of reason and passion is so deeply embedded in the construction of what is "legal' that it seems difficult even to imagine an international law that would not be entrenched in it. The very identity of international law seems based on its capacity to set itself on the side of reason, in opposition to the passionate, the irrational. The alignment of law with reason is under threat by the question of the legal status of the use or threat of use of nuclear weapons. This chapter examines the limits of (legal) reason and thereby, inevitably, looks beyond those limits, towards the 'subjective' element - passion - to which reason is, as Hume always insisted, but a humble slave. For it is in that realm that the issues of what people can know (faith) and who they are (identity) are settled and linked with how they understand and argue about the killing of the innocent.
