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The Evolution of the Soul$

Richard Swinburne

Print publication date: 1997

Print ISBN-13: 9780198236986

Published to British Academy Scholarship Online: November 2003

DOI: 10.1093/0198236980.001.0001

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(p.354) New Appendix G

(p.354) New Appendix G

Source:
The Evolution of the Soul
Publisher:
Oxford University Press

Libet's Experiments

[to Ch. 13 n. 11]

This point is the crucial consideration ignored in assessing the relevance of certain recent experimental work to the issue of human free will. In the 1970s H. H. Kornhuler and his associates did some experiments, which were repeated in the 1990s with refinements by Benjamin Libet and his associates. These consisted in asking subjects to flex an index‐finger suddenly at various times of their own choosing, while their EEGs were being measured. It was found that the recorded electrical potential appeared to build up a second before the moment at which, the subject claimed, he had decided to flex the finger.1 This appeared to show that the ‘decision’ was not, as it appeared to the subject, free but caused by the prior brain state.

But given that there were no issues of believed worth involved—subjects did not believe that it would be better in some way to flex the finger at 10.31 rather than at 10.32, desire alone would have determined their actions and free choice would enter only when desires were of equal strength. So one would expect subjects to flex their fingers when on balance they ‘felt like it’ and not when they did not. And desire being determined, one would expect the finger flexing to be determined. Only on rare occasions when desires were evenly balanced, would a free choice be required to determine the outcome. Free choice, I have argued, finds its paradigmatic expression in the situation of serious choices between alternatives which matter and for which reasons can be given, and it will therefore take time, during all of which there will presumably be an increase of electric potential, whichever way the choice goes.

Notes:

(1) See B. Libet, ‘The Neural Time‐Factor in Perception, Volition, and Free‐Will’, Revue de Metaphysique et Morale, 1992, 97, 255–72. For some discussions of these experiments, see Penrose, Shadows of the Mind, pp. 385–8.

(11) For a survey of recent psychological work on the effects of making people feel that they have a significant choice between alternatives, on their exercise of that choice, see H. M. Lefcourt, Locus of Control, Lawrence Erlbaum, Hillsdale, NJ, 1976.