O estado atual do legado de Benjamin Libet, sua coerência e seu impacto na filosofia da mente e no estudo do livre arbítrio

Abstract

Benjamin Libet’s legacy and the current status of his findings were analysed. Libets’ works on neurophisiology of voluntary act prompted a huge discussion on philosophy of mind in general and specifically on free will. The evidence from his main studies shows that the brain process that is responsible for the so called voluntary act begins preconsciously. The beginning of this neural process would be defined as the appearance of a readiness potential in eletroencephalographics recordings. This defies the common notion that a person can counsciously and freely choose how and when to act. The scientist holds the idea of consciously vetoing the act that has unconsciously begun and thus enable the exercise of free will. One would have about 200 milliseconds to use this veto power before the concrete onset of the respective action. Libet has tried to figure out a philosophic mind-brain interaction theory to compound with his empiric findings and so to shape what he understood as a human action and free will characterization. The reactions to these works were substantial. It seems to be a noticeable example of close interaction between philosophic and scientific knowledge, with a prospect of both enrichment and misunderstandings. A comprehensive review of Libet’s work and the main thinkers who commented on it shows that the discussion was quite rich and still has a great ammount at the present days. New methods of assessing brain activities and the recent replications of Libet’s experimental model emphasize the importance of his work. Some of his conclusions are now strengthened, in spite of the weakening of other points in his argumentations. His legacy can be ultimately regarded as an unavoidable reference to every person who investigates the free will issue.