A few years ago, there was an article in New Scientist by Dan Jones,entitled, Grand delusions: Why we’re determined to be free.  It began:

IT IS the year 2500. Physicists have long had a Grand Unified Theory of Everything and neuroscientists now know precisely how the hardware of the brain runs the software of the mind and dictates behaviour. Lately, reports have begun to emerge that computer engineers at the Institute for Advanced Behavioural Prediction have built a quantum supercomputer that draws on these advances to predict the future, including what people will do and when. Trusted sources say that IABP researchers have secretly run thousands of predictions about citizens’ behaviour – and they have never been wrong.

Suddenly, deep philosophical questions are making headlines as commentators sound the death knell for free will. On the face of it, the consequences of proving all our actions are predetermined look bleak. Psychological experiments have shown that undermining people’s sense of free will leads them to behave more dishonestly, more selfishly and more aggressively. But perhaps there is no need to panic. Some philosophers have found that our sense of free will is less threatened by determinism than the commentators suppose – so even faced with incontrovertible evidence that behaviour is predetermined, we still see ourselves as free and responsible for our own actions. Nothing will change.

Who is correct? Will the public buy this reassuring message? Or will the manifest truth of determinism kill off belief in free will, taking down notions of moral culpability and punishment with it? Will nihilism, moral disintegration and anarchy follow?

I composed a response, which I ended up not sending, but sent to Daniel Dennett instead, from whom I received a very nice reply, in which he attached a relevant article he’d recently written, Some Observations on the Psychology of Thinking About Free Will.  Here is the draft of my own response to New Scientist:

Dear New Scientist

Your cover story for 16^th April 2011, “Free will: the illusion we can’t live without”, perpetuates the illusion that free will is an illusion. Fortunately, by the end of the article, Dan Jones introduces some much-needed nuance, citing the philosopher Eddy Nahmias as making the argument “that instead of rendering conscious thoughts and decision-making irrelevant fictions, neuroscience could actually illuminate the biological basis of free will”.

Yes, it could, and indeed it does. It is a gross misrepresentation of neuroscience to portray it as describing our behaviour “as the result of a chain of cause and effect, in which one physical brain state or pattern of neural activity inexorably leads to the next”. Firstly, there is nothing inexorable about the way that “one physical brain state…leads to the next” – it may hinge, like weather, on something as finely poised as the proverbial butterfly in Peking – a spot of rain, a passing car, a familiar face in a crowd, as well as internal stochastic processes which may well include quantum effects. But secondly, even if we lived in a completely deterministic universe, for which we had a complete description, it would tell us nothing about “free will”.

Dan Jones reports a study by Nahmias himself, in which he apparently posed a futuristic scenario to a group of participants in which “the computer predicts the birth of a boy, Jeremy, and also that he grows up to rob a particular bank at a given time and day when he is 30” and asks the participants whether Jeremy acted “of his own free will”.

Most of the participants, thankfully, answered “yes”. Dan Jones’ article treats this phenomenon as evidence that we are naturally resistant to the concept that we do not have free will. I suggest that we are naturally resistant to the concept of idiotic scenarios. No computer will ever predict that a child will “rob a particular bank at a given time and day when he is 30”, because the reason that we regard brain-bearing creatures as decision-makers – choosers, will-ers – is that that’s exactly what they do. For any computer to predict Jeremy’s decision to rob a given bank on a given day, that computer would not only have to emulate Jeremy’s brain, but also model every single life event, from the molecules he ingests to the ideas he engages with, in order to predict the outcome of any decision faced by Jeremy. In other words, any infallibly predictive model of Jeremy’s life would be as large as Jeremy’s life itself.

Science is about making models of reality, i.e. incomplete representations of the real thing. A complete model of the universe would not only be the size of the universe, it would have to include the model itself, rendering it intrinsically Incomplete. What we do instead, in science, is to try to infer general principles, identify causal factors, compute probabilities – in other words make model that have useful predictive power. But all models must necessarily leave countless degrees of freedom within which events can take, literally, unpredictable turns. That is why despite our sophisticated technology, weather-forecasts remain unreliable beyond a few days, or even hours.

And our brains themselves are predictive model makers; we choose our actions by weighing up simulated outcomes. Freedom rightly, is the name we give this ability, and it is powerfully advantageous, in a Darwinian sense; it’s what makes us able to navigate our environment flexibly and productively.

Neuroscience is no threat to the concept of free will; neuroscience is the science of how we exercise our freedom to choose, and how factors that affect those choices are weighed in the decision-making process. We know now that there is no inner homunculus, pulling the levers of our brains. Nonetheless, the idea persists that there is an inner subjective “consciousness” that has no access to the levers (“has no free will”) but is nonetheless is a necessary postulate to account for our experience of existing. We have shorn the homunculus of all executive power, but retain it as titular head of self-government.

But no such postulate is necessary. “I” am a not helpless passenger borne by a mechanistic decision-maker whose decisions “I” am unable, Cassandra-like to influence but doomed, regardless, to observe. I am that decision-maker, and, as a member of the species homo sapiens, I have evolved not only to take what will bring immediate benefit to myself into account, in terms of sensory reward or evasion of risk, but also long-term benefit, as learned from previous experience of links between our actions and effects. Furthermore, I can also take advantage of the huge modelling capacity our possession of language endows us with to set abstract goals that also factor into my decision-making process – moral principles, for instance, such as “the greatest good for the greatest number”, or even the well-being of members of other species. Most of all, our language capacity allows us to reify the decision-making agents that populate our world, including ourselves – and the word we give to the decision-making agent that drives our own actions is “I”.

As Daniel Dennett repeats like a Greek chorus throughout his book Freedom Evolves: If you make yourself really small, you can externalize virtually everything. Conversely, it is by the very act of accepting responsibility for my decisions that I create what I call my self – a first person subject to which I attribute moral agency. There’s nothing illusory about that. It’s what I am.