Aggregation of Claims and Illogic

Abstract:     
Classical logic and probability theory produce in law the troublesome paradox of aggregation: On the one hand, logic seems to tell us that the aggregated likelihood of alternative claims elevates in response to probability’s rules; thus, if the plaintiff almost proves claim A and almost proves an alternative but independent claim B, then the plaintiff should win one. On the other hand, because the law requires each claim to meet the standard of proof, and thus refuses to apply the proof standard to the aggregation, the plaintiff loses in actuality; legal scholars despair in consequence — including Ariel Porat and Eric Posner in their new article Aggregation and Law.

Fuzzy logic, however, eradicates the aggregation paradox, by showing that the theories’ aggregated likelihood equals the most likely theory’s likelihood. The law is correct in applying this approach.

Number of Pages in PDF File: 11

Keywords: Evidence, standard of proof, fuzzy logic, procedure

JEL Classification: K41

working papers series