ABSTRACT
Reasoning with rules – both legal and/or moral – involves similar yet logically distinct ingredients. In both cases deliberation arises out of an actual set of events, which gives rise to a situation in which a choice or a decision is required. The problem of demarcation between legal and non-legal rules in no way impinges upon the other facets of this analysis. Legal, moral and other prescriptive rules maintain constant structural characteristics. In every legal decision a link is established between the actual events in the case and the protasis of the applicable rule. Complete rationality is preserved only when the actual events and the events which are contemplated in the rule or rules applied coincide. If they diverge, interpretation is at best partly rational. It then lies half way between trial by chance and rational choice.
