November 8th to 11th, 2004

3rd DAY - Wednesday - November 10th, 2004 - 7 p.m.
3rd Session
2nd Lecture

Abduction in Normative Reasoning
Prof. Dr. Juliano Souza de A. Maranhão
University of São Paulo, Brazil

[Abstract]
The paper studies the inference by the legal interpreter of the best explanation for the intentions of the legislator from a basic set of norms. We claim that such inference is abductive, in the sense of Peirce. Such abduction, nevertheless, is not based on alternative causal explanations tested by a set of observations, but on alternative arguments of practical reason about the goals pursued by the legislator, which could have motivated him to issue an obligation or a permission.
The difficulty in this form of abductive inference lies in the possibility of conflict between the most plausible justification (intentions of the legislator) to the set of norms, and the attribution of meaning to norms in this set (interpretation). In such cases, the conflict is a reason to modify the normative set itself, through the specification of new conditions of application of its norms, according to the intentions of the legislator. That is, the intentions are inferred (abducted) from the set of norms, but cause modifications in that very set (or in the interpretation of its norms) until coherence is reached among them.
We propose an abstract model of revision of normative systems in order to represent such constructive process of legal interpretation.

Center for Pragmatism Studies
Philosophy Graduate Program
Departament of Philosophy
Pontifical Catholic University of São Paulo - Brazil