A leading neuroscientist examines their relationship

Does neuroscience undermine free will and moral responsibility?  This question formed the basis of Walter Sinnott-Armstrong’s recent lecture to a packed auditorium in Geddes.  Armstrong is a member of the Kenan Institute for Ethics and professor of practical ethics at Duke University.

A commonly held view of neuroscience is that it either poses a threat to the existence of free will, or that its findings are irrelevant to the understanding of our will.  Armstrong stated that “many people fear neuroscience establishes determinism and (therefore) leads to absurdity (when we try to hold people responsible for their actions).”

In order to examine the accuracy of this view Armstrong outlined two key questions, whether anything causes our will and whether our wills are truly efficacious.

Through his examination of these questions, Armstrong argued that neuroscience does not, and cannot, undermine the existence of our free will. The work done in neuroscience finds only imperfect correlations between causes and effects, and therefore cannot be taken as proof for causation.  Furthermore, against the other side of common misconception, neuroscience is not irrelevant but rather helps to illuminate our understanding of free will.

Armstrong drew upon an example of a man who, with no previous history of involvement with child pornography, develops a tendency towards watching and collecting it.  At the same time this develops he also complains of intense headaches and admits to knowing that his actions are wrong and that he feels guilt.  After a while the man visits the doctor and is discovered to have a growing brain tumor.  The tumor is removed, and the tendencies vanish.  Years later the tumor returns, along with the tendencies.

Armstrong explained that today this man would legally be held criminally responsible.  He acted voluntarily (his tumor did not force him to act), he knew his actions were wrong, and he could have sought medical help sooner.  The found neurological evidence does not eliminate the reality of the exercise of his free will. It does, however, help illuminate our understanding of it.

Although the found neurological evidence does not technically entail a causal relationship between the tumor and the man’s tendencies, in similar cases causation is often assumed because of the extremely tight correlation.  This assumed causation, coupled with the fact that society typically identifies the tumor as something external to the man causes many to claim that his actions were not caused by himself but rather his tumor.

Armstrong explained that this example of the way in which neuroscience illuminates our investigation of free will and the role it plays in our attribution of moral responsibility.  He claimed that such evidence should prompt us, and more specifically our legal system, to widen the traditional list of ‘excuses’ that diminish or eliminate moral responsibility.

For example, adolescents and children under a certain age are not held responsible to the fullest degree for criminal actions, because of our knowledge that their brains will significantly develop.

Armstrong also discussed the concept of mechanism.  Frequently used to support the view that neuroscience eliminates free will, this view describes our thought processes in purely physical terms, devoid of reference to conscious mental states or goals.

Armstrong argued that this position is weak by discussing the concept of “multiple realizability.”  For example, a friend could give you a dollar in many different forms – four quarters, a one dollar bill, and so forth.  You would then thank them for giving you a dollar either way, not for the form in which they gave it to you.

According to Armstrong, “multiple realizability” parallels the distinction between the mental and the neural.  If a thought process can be completely described using only physical, neurological processes, this does not negate the possibility of mental processes having a true causal force in our thoughts and actions.

Armstrong concluded that we can see that “neuroscience does not undermine responsibility in general, but (rather) it does raise fascinating questions about particular cases (involving free will.)”

Katie Finley is a junior philosophy, theology, (pseudo) art major who collects bottle caps.  If you would like to make a donation (and earn her unending gratitude) please contact her at kfinley2@nd.edu.