Most neuroscientists today are materialists who believe that everything we do is determined. But this ignores our rationality and free will. There must be a better way.
In a recent issue of Scientific American, Christof Koch, a prominent neuroscientist based at the California Institute of Technology, gives free will a qualified thumbs-down. His approach demonstrates the uneasiness that his colleagues have about the prevailing materialistic interpretations of scientific data. It also shows the inability of neuroscience to grapple with the notion of human freedom.
Koch steps the reader through familiar arguments of reductionist psychology and neuroscience. Criminal choices reflect a mix of upbringing and brain chemicals. Chaos and quantum theory are harnessed to suggest that freewill is a material phenomenon. He says ‘we cannot rule out the possibility that quantum indeterminacy … leads to behavioural indeterminacy’. He cites Benjamin Libet’s demonstration in 1983 that the brain primes for movement prior to any conscious decision to move, Harvard psychologist Daniel Wegner’s 2003 demonstration that feelings of intentionality can be mistaken, and the work of neuroscientists Desmurget and Sirigu showing that electrical stimulation of areas of the cortex provokes desires to move one’s foot or roll one’s tongue. Surely free will is an illusion!
Koch seems to intuit that a philosophical solution is needed if a minimum of human freedom is to be preserved, but he rejects what Damasio called ‘Descartes’ Error’. He alludes to the unsustainable arguments of dualism, a position adopted in practice by Jeffrey Schwartz, co-author of The Mind and the Brain (2002), who insists that mental events can precede biological events in the brain. As a substitute for dualism, Koch proposes ‘compatibilism’, that man has the capacity to follow his desires.
But in effect he is saying that our chemical programming determines our desires and our actions.
Although he has described himself as a reductionist in his 2012 book Consciousness: Confessions of a Romantic Reductionist, Koch insists on a pragmatic approach that ascribes a limited freedom to man’s efforts at self-determination. He says, ‘Freedom is always a question of degree rather than an absolute good that we do or do not possess’, and he cites rare individuals, Gandhi and an immolating Buddhist monk, as evidence that determinism does not hold all of us in its clutches.
Koch is basically in a muddle. Belief in free will is irrational, but some free will exists. Surely it would be sounder for him to be a denialist like Larry Squire in Fundamental Neuroscience (2008). This author asserts baldly that all behaviour and all mental life have their origin in the structure and function of the nervous system. Similarly Eric Kandel, a Nobel laureate, wrote in Principles of Neural Science (2001): ‘All biological phenomena are properties of matter’. These are standard reference texts.
Some neuroscientists defend human freedom through ‘emergentism’. Emergentism holds that non-material realities can emerge from purely material origins. A prominent proponent of this position is the eminent neuroscientist Michael Gazzaniga who argues in Who’s in charge?: Free will and the science of the brain (2011) for a non-reductionist ‘strong emergent’ paradigm in which the emergent ‘is more than the sum of its parts’.
Yet it is hard to see how human freedom can exist in a being which is wholly material and therefore determined. At its basis emergentism, too, is a physicalist explanation and, for this reason, it is logically flawed.
So the attempts of neuroscientists to avert determinism appear doomed. Dualist approaches fail to explain how physical events (such as emotions) cause mental experiences and how intention can lead to action; physicalist explanations deny man’s freedom. Although experience and observation manifest an evident, albeit conditional, freedom enjoyed by man, if there are no philosophical grounds to hold this view and if the neuroscience is opposed to it, we must conclude that man is not free. We should stop pretending.
But before throwing up our hands, let’s review our options. There are only five possible explanations for the presence of rationality, and hence free will, in human beings.
(1) Human beings are puppets of a rational principle beyond themselves. This is manifest nonsense as it removes agency from mature human beings.
(2) Reductive materialism defines matter as the functioning agent, and argues that all human behaviour has its explanation in cells, currents, neurotransmitters, etc. This is a deterministic position and is ultimately a denial of rationality; an assertion that rationality and human freedom are essentially illusory.
(3) Substance dualism defines the soul as the functioning agent. This is the position of Schwartz, but it leads to insuperable contradictions in accounting for causation and for interaction between human beings and physical experience.
(4) Non-reductive materialism argues that rationality emerges from matter itself. This is the position of Gazzaniga. Yet an emergent rationality must be tied to the determinism inherent in matter; it cannot explain the capacity to grasp universals or human freedom. As both of these are evident realities, non-reductive materialism is ultimately a self-contradictory position. Furthermore, to propose chaos and quantum physics, or subjective ‘qualia’ (ie feelings), as emergent explanations of personhood and freedom is illogical or mystical.
(5) The hylomorphic solution, originating in Aristotle and reproposed by contemporary philosophers such as John Haldane and Martha Nussbaum, is far more subtle and satisfying. The word hylomorphism means ‘matter and form’ understood as the underpinning constituents of substance. The hylomorphic understanding of human nature is founded on the observation that human nature is essentially of a different order from that of a living animal or a non-living thing.
Hylomorphic metaphysics contends that, to account for freedom and rationality, there must be a principle for human activity, a form transcending the physical and having a non-material source. As only the acting person is the agent, this principle does not constitute a separate substance; it is therefore a functional principle of being and acting, bestowing unity and of personhood in which the mental and the physical are perfectly integrated.
Aristotle named this principle of activity as ‘the rational principle’ or ‘the soul’.
Such a functional understanding of the soul appears remarkably consistent with the teachings of the philosophers Plato and Aquinas about ‘participation’. Aquinas taught that the human soul is none other than participation in perfect ‘act’, participation in the being of God himself. This line of argument leads to the conclusion that the soul, a gift of functional participation in the divine act of being, empowers us to act with freedom.
Back to basics
Hylomorphism grates in a world that prefers to separate religion and science. Not all ages have had this difficulty. Aristotle, held by many to be the world’s first systematic scientist, argued for the immortality of the soul 350 years before Christ. Physics is, he argued, the study of physical causes; metaphysics, the study of causes that transcend the physical.
Yet, the prevailing position in neuroscience in 2012 is materialism, either reductive or non-reductive. But materialism cannot account for our free will. It is time to rediscover the hylomorphic understanding of man.
Aristotle’s solution is logically consistent. It accounts for what we experience every day: rationality and freedom within certain constraints of genetics and upbringing. Without an acceptance of hylomorphism, the neurobiology of abstraction, of human freedom, of personal agency and interpersonal relationships will remain undervalued. Unless neuroscientists acknowledge the rich complexity of the human person, the role of truth, freedom and love in human fulfilment will remain phenomena which they see and hear, but which they will never understand.
Andrew Mullins is headmaster of Wollemi College in Sydney.