DE LA INTERPRETACIóN DE LA LEY A LA ARGUMENTACIóN DESDE LA CONSTITUCIóN: REALIDAD, TEORíAS Y VALORACIóN

this article offers a comparative study of the theory of legal interpretation particular to legal positivism, which is the dominant legal theory associated with the rule of law, and the vision of the interpretive theory of the constitutional state. the central features of the positivist view of interpretation are: an understanding of legal science as a theoretical-descriptive science, the absence of assessments, and adherence to the letter of the law and legal certainty as the sole criteria to guide the work of interpreter. in constitutionalism, legal interpretation is re-assessed as a task involving practical reason, which implies the presence of substantial values in the law, and requires the interpreter to use argumentative techniques that go beyond mechanical application of the law. all these assertions are contrasted, in the end, with the interpretive theory of classical legal realism, which is presented as the best way to understand the work of the interpreter, and in whose thesis it is possible to assume many of the contemporary theories on interpretation.