Metaphorical Use of Algorithm in Legal Reasoning

The current use of big data in the legal framework suggests the idea of algorithm as a new topos of the legal rhetoric. Indeed, in addition to the “rhetoric of algorithm”, an “algorithm of rhetoric” may also exist, in strict connection with an anthropological structure. Even leaving aside its epistemic value, the algorithm is in fact always experienced by the jurist through a metaphorical process, in a very similar way, for instance, to the metaphorical use of graphs in economics (McCloskey). That said, the reasoning about big data is metaphorical as well, and this allows us to believe that there is still a role for pathos and ethos within the legal reasoning. Moreover, and most importantly, the ideal to which the data-based knowledge (the so called dataism) aims—that is, the pretension of being able to map all that there is to know—is metaphorical, too. In this paper I will discuss algorithms and big data in the guise of new topoi. The aim of this paper is therefore to imagine a philosophical-juridical semiotic by means of which it is possible to highlight the persistent difference between reasonableness and reason in the judge’s work. Vis-à-vis algorithms and big data, as well as the rules of law, the judge does not act as bouche de la loi, but rather practices a reason which is irreducibly rhetoric and related to the humanities.