I've excerpted parts of Cave's essay below and follow the excerpts with critical comments.
Cave observes that,
In recent decades, research on the inner workings of the brain has helped to resolve the nature-nurture debate—and has dealt a further blow to the idea of free will. Brain scanners have enabled us to peer inside a living person’s skull, revealing intricate networks of neurons and allowing scientists to reach broad agreement that these networks are shaped by both genes and environment. But there is also agreement in the scientific community that the firing of neurons determines not just some or most but all of our thoughts, hopes, memories, and dreams.It should be noted that the agreement to which he refers is a tacit consequence of a metaphysical assumption shared by many researchers - the assumption that there are no non-physical, non-material factors at play in the universe or in human beings. If physicalism or naturalism are true then determinism follows, but there's no good reason to think that either are true and lots of good reasons to think they're not.
He goes on to say that,
We know that changes to brain chemistry can alter behavior—otherwise neither alcohol nor antipsychotics would have their desired effects. The same holds true for brain structure: Cases of ordinary adults becoming murderers or pedophiles after developing a brain tumor demonstrate how dependent we are on the physical properties of our gray stuff.Quite so, but it doesn't follow from the fact that changes in the physical brain cause changes in behavior that therefore the physical brain is all that's involved in behavior. A viewer can change the physical settings on his television and thereby change the image on the screen, but it would be foolish to conclude that therefore the image can be completely explained in terms of the workings of the television set.
Many scientists say that the American physiologist Benjamin Libet demonstrated in the 1980s that we have no free will. It was already known that electrical activity builds up in a person’s brain before she, for example, moves her hand; Libet showed that this buildup occurs before the person consciously makes a decision to move. The conscious experience of deciding to act, which we usually associate with free will, appears to be an add-on, a post hoc reconstruction of events that occurs after the brain has already set the act in motion.This is a misreading of Libet's work, a clarification of which can be read here. Libet himself believed that human beings had free will. It would've been peculiar of him to hold this view after he had proven that the view was wrong.
The challenge posed by neuroscience is more radical: It describes the brain as a physical system like any other, and suggests that we no more will it to operate in a particular way than we will our heart to beat. The contemporary scientific image of human behavior is one of neurons firing, causing other neurons to fire, causing our thoughts and deeds, in an unbroken chain that stretches back to our birth and beyond. In principle, we are therefore completely predictable. If we could understand any individual’s brain architecture and chemistry well enough, we could, in theory, predict that individual’s response to any given stimulus with 100 percent accuracy.If the system which produces our choices is indeed "a physical system like any other" then determinism is very probably true, but the assumption that our choices are solely the product of physical causes is an unprovable metaphysical statement of faith. If we are also possessed of an immaterial, non-physical mind or soul, as many philosophers believe, that faculty could possibly function as a locus of free choice. The only reason for thinking that such minds don't exist is an apriori commitment to physicalism.
Cave next addresses the human and social consequences of a widespread belief in the truth of determinism. They're not good:
Determinism, to one degree or another, is gaining popular currency....This development raises uncomfortable—and increasingly nontheoretical—questions: If moral responsibility depends on faith in our own agency, then as belief in determinism spreads, will we become morally irresponsible? And if we increasingly see belief in free will as a delusion, what will happen to all those institutions that are based on it?Some philosophers have suggested that given the consequences of living consistently with an awareness of the truth of determinism that the philosophical elites ought (strange word in this context) to deceive the masses and just not tell them about it. The elites should foist upon the public a kind of Platonic Noble Lie. Cave, however, demurs:
Believing that free will is an illusion has been shown to make people less creative, more likely to conform, less willing to learn from their mistakes, and less grateful toward one another. In every regard, it seems, when we embrace determinism, we indulge our dark side.
[F]ew scholars are comfortable suggesting that people ought to believe an outright lie. Advocating the perpetuation of untruths would breach their integrity and violate a principle that philosophers have long held dear: the Platonic hope that the true and the good go hand in hand.This is a strange reaction, it seems, for if determinism is true, why should scholars be uncomfortable promoting a lie? What would make such a tactic morally wrong if they really had no choice in employing it?
Saul Smilansky, a philosophy professor at the University of Haifa, in Israel, has wrestled with this dilemma throughout his career and come to a painful conclusion: “We cannot afford for people to internalize the truth” about free will.There's something very odd about a metaphysical view - physicalism - the implications of which are so destructive that they can't be shared even among many of those who accept the view. If a belief is such that one cannot live with it consistently there's probably something deeply wrong with the belief.
Smilansky advocates a view he calls illusionism—the belief that free will is indeed an illusion, but one that society must defend. The idea of determinism, and the facts supporting it, must be kept confined within the ivory tower.
Physicalism, however, does entail determinism and as Cave points out in his essay, the consequences of determinism are bleak. For instance, if determinism is true then:
- Praise and blame, reward and punishment, are never deserved since these assume that the recipient could have acted otherwise than he or she did act.
- There are no moral obligations, no moral right and wrong, since morality is contingent upon uncompelled free choice.
- There's no human dignity since dignity is predicated on the ability to make significant choices.
Philosopher John Searle offers an antidote to the determinism described by Cave in this Closer to the Truth interview: