The Neuroscientific Challenge to Moral Realism

Abstract

During a hiking trip in Norway in the early 1970s, neurologist Oliver Sacks, a leading expert on neurological disorders, found himself dealing with his own strange ailment following a fall down a cliff that left his leg severely damaged. Recovering in a local hospital, Sacks found that he had lost his ability to move muscles in his damaged left leg. The psychic disconnect that he experienced between himself and his leg was so profound that he began viewing it as an alien object that was somehow attached to his body. Finding himself unable to cause any sort of muscle movement in his injured limb, he became deeply disturbed at having “forgotten” how to control his leg. It seemed to him that his leg was simply not responding to his efforts to move it as it had in the past. Two weeks after sustaining the injury, Sacks noticed involuntary twitching in his quadriceps muscle. According to him, such movements “did not go with any feeling of intention or volition” (1984, 118). What began as willing without action had now become a matter of action without willing. What happened next was described by Sacks as the “convulsive reunion of body and soul” (131). Here is how he described it:

When I awoke I had an odd impulse to flex my left leg, and in that selfsame moment immediately did so! Here was a movement previously impossible … And yet, in a trice, I had thought it and done it. There was no cogitation, no preparation, no deliberation; there was no trying; I had the impulse, flash-like—and flash-like I acted. The idea, the impulse, the actor, were all one—I could not say which came first, they all came together. (129)