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On free will, the brain, society and Michael Gazzaniga: one is not like the others

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Michael Gazzaniga recently stopped by UBC for the Quinn Memorial Lecture and I had a chance to listen in on his talk about free will, which I assume is taken from his most recent book on the topic. Past Quinn lectures are available on Youtube, so I imagine the Gazzaniga talk will uploaded at some time in the future.

Briefly, Gazzaniga takes a fairly simple perspective that I share: free will is nonsensical.

The main problem with the concept is the impossibility of defining what there is to be free from. If we live in a world where the rules of causality apply, then free will implies action that is dis-engaged from this causal system. This either means that we need to evoke some external force or soul that guides our mindless bodies, or it suggests a paradox, wherein all events are caused by other events, except for the inexplicable human mind which somehow eludes this core feature of reality. (In the former case, we might ask what causes this soul to act, or what exactly this external reality looks like, but then we would be getting ahead of ourselves…).

On the other hand, if this universe does not obey rules of causality at the macro level, then even a “freely acting will” is going to have difficulty influencing events, as the will must, therefore, influence a non-responsive system. I like to think about this as being analogous to an astronaut swimming in space: there’s no appreciable matter to push against, so the forces which allow humans to swim in the ocean don’t provide any leverage for altering the astronaut’s motion in space. A free will (or soul) with no causal system to act on similarly cannot influence the motion of the body it inhabits: actions become uncoupled desires and all of a sudden this will is not “free” but “stranded”.

One thing which I did not appreciate especially much was how Gazzaniga rationalizes this failure of free will. He takes a strong deterministic approach, describing the brain as an automatic or mechanistic system. This is not strictly true, as Gazzaniga implicitly appears to accept, as external or “environmental” events can influence this system so over the long run its internal mechanisms cannot be described without studying how the brain (and the person) interacts with the external world. But as I point out above, this is irrelevant: free will can only plausibly exist in a causal universe so we don’t need to adopt a strict view of determinism to support free will.

Gazzaniga skips over much of the evidence to suggest that the mind and brain cannot be dissociated (e.g. people with brain damage, stimulation experiments) and jumps right into how he thinks the brain creates the mind. His approach wasn’t discussed with much clarity in the talk, but if I understand it correctly it is pretty typical. Gazzaniga calls it “layered modularity”. In effect, he treats distinct units of the brain as isolated modules (e.g. visual cortex is a module, the amygdala is a different module) which perform different computations. These modules somehow interact within a deep or “layered” neural network that is distributed across the brain and can integrate these inputs to produce psychological states. Gazzaniga believes we can understand which networks correspond to which states within a decade, though it appears he trusts the BRAIN project to solve this major technical challenge. (I actually thought this section was a little misleading: are the modules whole brain regions, or sub-regions? Are these modules functionally distinct, or do they perform computations in tandem, sending and receiving information between each other to fine-tune their “modular” operations? Gazzaniga doesn’t say.)

Gazzaniga also doesn’t get into any of the really meaty issues. He argues that whereas the brain is deterministic, people are free–which is a bit of a mind-bender. Essentially, he’s saying that it is social constructs which assign responsibility and so we ought to focus on the social world to figure out who deserves blame and reward. While this is essentially true (if a little obvious), it’s also a bit of a cop-out. It is meaningless to argue free will does not exist if we don’t derive some useful wisdom from this point. Gazzaniga explicitly declares his unwillingness to state exactly what this point is.

So, I will tell you.

If free will does not exist then blame cannot be assigned objectively or a priori. There is no absolute or undeniable basis by which we make our judgments: instead we must rely upon fuzzy, malleable concepts like social and individual good, neither of which can be defined objectively. We have to rely upon subjective measures of harm like wealth, happiness, quality of life and a variety of others. But none of these can be measured easily, and their “goodness” may change over time and thus must be re-evaluated. This situation immediately suggests that social and legal policies must be evidence-based. By this I mean: there can be no prior judgment about who should be punished or rewarded and for what. We can still build starting points like “murder is bad because it harms many people and benefits virtually no one”, which is about as empirically obvious as it gets. But when it comes to dealing with these issues, we need to accept that there may be some unexpected or disagreeable conclusions which arise from the reality.

A second point worth noting is the one certain and objective claim which can be made from this position. If there is no free will and the responsibility of those who do wrong is socially and subjectively derived, then the injury to these people–the wrongdoers–must be included in evaluating the best way to deal with criminal behavior. Is a murderer truly better off in his position? Probably not. If this is the case, then we are simply adding harms on top of harms by needlessly punishing those who break the law. (Keep in mind, the corollary of this is that if punishment actually works to cut back on harms, then we should keep it up, no matter how unsettling this might be to liberals.)

A final point I would like to make deals with how the individual ought to assign personal responsibility. The discussion above focuses mostly on socially-defined responsibilities. But what can the individual do for him or herself?

While Gazzaniga argues that the brain is powerfully deterministic, he ignores the fact that once a person has reached adulthood, a significant proportion of the constraints on the mind and action are already in place. Certainly, people can evolve and external events can have a big influence on the individual, but the basic (neural) groundwork has largely been laid and should remain fairly consistent over time for most people. Therefore, even though we don’t control what gets us to this point (e.g. adulthood), once we have reached some level of development the mechanistic events which control our actions are most certainly not arbitrary or random (e.g. development is a structured process, but the differences in how people develop are arbitrarily assigned) but are highly consistent with “who I am”. In this sense, a belief in personal responsibility is less illusory than we might imagine and if this belief may potently influence how individuals act in the future, then it’s worth considering.

A sense of agency may be illusory on some level, but this isn’t just something we do to “rationalize” our uncontrolled actions, as Gazzaniga argues his Split-Brain patients attempt to do. In reality, if there is a close correlation between how I believe I would act in specific situations and how I do act in these situations, then my beliefs are not bizarre rationalizations–they are the most accurate predictions I can make about myself, given what I can consciously access. Therefore, when my actions do not match my beliefs, it makes perfect sense to try and update my beliefs to explain the situation. In one-off situations this takes the form of rationalization. But if this discrepancy is consistent, then something has to shift. There is a whole literature on this, it’s called cognitive dissonance.

So where are we at on free will? Well, it’s still dead. Very, very dead. But as we can see, even without this objective basis for morality or right action we can still address questions of responsibility and moral laws from a more subjective point of view without washing away all of our legitimacy. To work though, this subjective view needs to be grounded in empiricism: there needs to be some way of accessing what is good and what is not and to update these norms as things change. I don’t see this as a way to totally upend the moral prescriptions we have relied upon for centuries: simply a way to open up those prescriptions which are based on misunderstanding rather than reality.


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