The Christmas issue of the New Statesman (you can buy a copy here), guest-edited by Richard Dawkins, includes a brilliant essay by the neuroscientist and atheist author Sam Harris on the illusion of free will. Here, for Staggers readers, is a sneak preview.

Even though we can find no room for it in the causal order, the notion of free will is still accorded a remarkable deference in the scientific and philosophical literature, even by those who believe that the mind is entirely dependent on the workings of the brain. However, the truth is that free will doesn't even correspond to any subjective fact about us, for introspection soon grows as hostile to the idea as the equations of physics have. Apparent acts of volition merely arise, spontaneously (whether caused, uncaused or probabilistically inclined, it makes no difference), and cannot be traced to a point of origin in the stream of consciousness. A moment or two of serious self-scrutiny, and you might observe that you decide the next thought you think no more than you decide the next thought I write.

All of our behaviour can be traced to biological events about which we have no conscious knowledge. In the 1980s the neurophysiologist Benjamin Libet demonstrated that activity in the brain's motor regions can be detected some 300 milliseconds before a person feels that he has decided to move. Another lab recently used functional magnetic resonance imaging data to show that some "conscious" decisions can be predicted up to ten seconds before they enter awareness (long before the preparatory motor activity detected by Libet). Clearly, findings of this kind are difficult to reconcile with the sense that one is the conscious source of one's thoughts and actions.

For better or worse, these truths about human psychology have political implications, because liberals and conservatives are not equally confused about them. Liberals usually understand that every person represents a confluence of forces that he did not will into being - and we can be lucky or very unlucky in this respect. Conservatives, however, have made a religious fetish of individualism.

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