An intellectual history of the "Libet experiment": embedding the neuroscience of free will

In 1983, Benjamin Libet and colleagues published a paper that profoundly changed psychological, philosophical and neuroscientific discussions about free will. Briefly, Libet showed that the subjective experience of conscious intention followed the readiness potential (a key neural marker preceding voluntary action), rather than preceding it, as an intuitive dualism might imagine. The experiment itself has been much debated, and often criticized, but its positioning and context within the general history of mind sciences has been neglected. This paper takes a history of ideas approach, and shows that the Libet experiment represents the convergence of two distinctively 19th century traditions: a philosophical interest in volition and conation, and a physiological tradition of measuring timing delays. A discussion of the afterlife of Libet's result identifies a number of crucial methodological controversies and concerns, to which Libet's arguments from temporal precedence may be particularly vulnerable. Experimental methods for studying volition are inevitably constrained by the fact that, by definition, the input signals for voluntary action are under the control of the participant, and not, as is usual, under the control of the experimenter. Understanding the broader embedding of the experiment within the scientific study of volition may be useful for guiding future research using the same methods, or indeed alternative methods.