Goal-based theory evaluation

In his paper ‘Some arguments about legal arguments’, Thorne McCarty [1] pleads for a theory construction approach in AI and Law research. Legal materials should not be taken at face value, but are amenable to reconstruction. This line of argument is well in line with a teleological tradition in legal theory that has historical roots in the * > around 1900 [2, 3] and which is more recently exemplified by the work of, amongst others, Dworkin [4, 5, 6], MacCormick [7], Alexy and Peczenik [8], which emphasises that the law should be constructed as a coherent whole. In this paper I follow McCarty’s suggestion and contribute to a theory construction approach of legal reasoning. In particular I propose a formalisation of one part of Dworkin’s version of a coherence theory of the law. In section 2 this version is described as ‘The Model of Principles’. In section 3 of this paper I describe part of Dworkin’s model informally. Section 4 provides a formal characterisation of this same part, while section 5 puts the formalisation to use in an example.