Tuesday, January 4, 2011

Is free will nothing but an illusion?

By Steve Rensberry  

 It is commonly believed that upwards of 90 percent of the activity that goes on within the individual human brain stems from unconscious processes, whether for the purpose of interpreting visual or auditory stimuli or for the regulation of such basic things as breathing, eating and memory formation.   
   The observation raises a number of questions. Just how free are we if such a large part of our brain (or mind if you will) lies outside the realm of conscious control? Can a person rightfully be held responsible for behavior which is largely the result of unconscious brain activity? We feel as though the choices we make are done with some degree of conscious volition. But are they really?
   University of California researcher Benjamin Libet (1916-2007) is well know for his work in the early 1970s that was aimed at trying to answer this exact question.  In one instance, Libet's investigation involved an analysis of what are called sensation thresholds, and the accompanying neural activity that goes along with it. As the name suggests, a sensory or sensation threshold is defined on various levels as the precise spot at which any particular stimulus can be detected, recognized, perceived and ultimately  terminated.
   Libet's experiments lead him to an examination of the Bereitschaftspotential, or readiness potential (RP), a measurement of the unconscious neurological activity within the brain's motor cortex prior to conscious action. His experiments made use of a cathode ray oscilloscope, an electrocencephalogram (EEG) monitor, an electromyograph (EMG), and a great deal of meticulous scientific observation.
   The essence of the groundbreaking discovery by Libet and other researchers was that decisions supposedly made by a subject's conscious mind were, on a very fundamental level, preceded by a noticeable build up in unconscious brain activity--in effect nodding in the direction of the decision even before the subject himself became aware of it. The conscious mind appeared almost to play a secondary role in the process of exercising choice. It could veto or alter that choice, but it did not appear to be the primary source.
   Author Fred Alan Wolf writes in The Dreaming Universe:
   "What Libet has found can be said simply, but I doubt if it will be believed simply. It is that our minds operate mostly unconsciously. This means that we make decisions and respond to sensations from the outside world totally unconsciously. We only become conscious of the outside world much later (about half a second later -- a long time on the neural level), after the slings and arrows of our fate have already passed us by or struck us. But then there is an interesting twist: we refer the later moment of conscious awareness back in time to the moment of sensation and out in space to the location of a stimulus even if it is outside our bodies." (Fred Alan Wolf, The Dreaming Universe, Simon and Schuster, 1994).
   Although his experiments suggest a secondary role for the conscious mind in the decision making process, Libet defended the concept of free will.
   "The role of conscious free will would be, then, not to initiate a voluntary act, but rather to control whether the act takes place. We may view the unconscious initiative for voluntary actions as 'bubbling up' in the brain. The conscious-will then selects which of these initiative may go forward to an action or which one to veto and abort, with no act appearing," Libet says in an essay entitled Do We Have Free Will? published in the Journal of Consciousness Studies.
   Such an interpretation may be harmonious with some ethical and religious views about the primacy of free will and moral responsibility, but Libet has no such sympathy for those who would argue that someone should be held accountable merely for the "urge" to commit a reprehensible act.
   "The mere appearance of an intention to act could not be controlled consciously; only its final consummation in a motor act could be consciously controlled. Therefore, a religious system that castigates an individual for simply having a mental intention or impulse to do something unacceptable, even when this is not acted out, would create a physiologically insurmountable moral and psychological difficulty," Libet says. 
   Indeed, if thoughts alone are enough to render a conviction, then the religious thought police have all the ammunition they need to keep their followers at their knees, the evidence not withstanding.
   We won't solve the free will debate in one article, nor do I think we can get very far without first defining what it is we really mean by "free" and "will."
   You can read more about Benjamin Libet's views and work at Machines Like Us.

Carl Sagan on God, Faith and Religion