What Can One Expect from Logic in the Law?(Not Everything, But More than Something: A Reply to Susan Haack)

After examining Holmes’ criticisms of Langdell’s conception of legal science as being constructed only by means of axioms and their corollaries, not unlike what one finds in a book of mathematics, and taking into account that both Langdell and Holmes had a rather rudimentary idea of logic, Susan Haack, an outstanding logician, poses a question about the perspectives of applying to the law the far more powerful techniques of modern logic. Her answer to this question strikes one as rather pessimistic: she believes that a Langdellian program, updated by means of different logical techniques, can only provide a modest contribution to legal science: something but not everything. One of the targets of her criticism is Normative Systems by Carlos Alchourrón and Eugenio Bulygin (1971), an approach that she takes to be a typical case of the new logical theology. If by “logical theology” she understands the axiomatization of a legal system, deriving answers to specific legal questions from a priori logical considerations, and choosing best interpretations of legal texts on logical ground alone, then her criticism is misdirected. Normative Systems has nothing to do with such logical