If you knew everything about how the human brain works, would you know everything about humanity? A growing number of scientists nowadays say Yes, including Susan Greenfield in her recent book, ID: The Quest for Identity in the 21st Century. However, I find her attempt to prove that we are our brains less than convincing.

The author is no scientific lightweight. As director of the Royal Institution and professor of pharmacology at Oxford University, Baroness Susan Greenfield is one of the world’s best-known scientists. She is even known in the Antipodes as an honorary Australian of the year.

Greenfield writes with mastery about the history and breadth of brain exploration. Her explanations of recent breakthroughs such as the interplay of multiple brain regions in every brain function and of the key role that lower, sub-cortical, regions of the brain exercise in higher brain function, are superb. She is also refreshingly frank about the current limitations of research and the daunting complexity of the task that scientists face.

She is particularly good when she describes how experience changes our brains and about the impact of powerful sensory experiences. Her warnings about how the brain changes because of contemporary teenage lifestyles are sobering: an inability for reflective thought, attention and learning problems caused by a screen culture, addictions, cultures of passivity and hedonism "obliterating the individual", and the virtually irreversible modifications wrought by cannabis usage.

The discussion is grounded squarely on recent research and is aligned with landmark texts of popular sociology like Neil Postman’s Amusing Ourselves to Death and Oliver James’s Affluenza.

But ultimately ID is disappointing. Greenfield thinks that neuroscience is on track to answer the big questions of How can I be happy? and What is the meaning of life? But instead of simplistic analogies and rambling ruminations on the effects of environment on personality there is a need for a reasoned understanding of personhood and human nature. Although many philosophies are arcane constructions of the mind, lack common sense, seem out of date, or are just bluntly contradictory there is at least one philosophy which she could have relied upon, one which fulfils the five requisites for being compatible with science.

> Both must be concerned with existent reality.
> Both must seek truth and subscribe to the objectivity of that truth. Philosophical and scientific truth cannot be in contradiction.
> Both must uphold the reliability of sense evidence and admit no other forms of data.
> Both must use reason to explore sense evidence.
> Both must accept the causality evident in the world around us.

These common sense tests effectively rule out many philosophies -- but not all. Aristotle laid the foundations for the development of modern science with his insistence on factual knowledge and empirical investigation. It is to Aristotle, too, that we must turn for a compatible philosophy.

Let us examine three key areas in which contemporary neuroscience could make good use of Aristotle’s insights.

That reality transcends the material was evident to Aristotle. He grappled with proofs of the non-material dimensions of human nature, and even demonstrated the immortality of the soul. He held that the rational, non-material, dimension of being transcends matter. Hence it can neither provide direct data on it, nor explain its origins.

Modern neuroscience rightly spurns dualism, the notion that the mind directs the body "like a pilot in a boat" or like a "ghost in a machine". The evidence is that the machine drives itself. Greenfield contends that every thought has "a physical correlate" and despite lip service draws the conclusion that there is only a clever machine.

But Aristotle, who also believed that every psychological event has physical correlate, came up with a completely different explanation that wholly fits the evidence. He concluded that matter and non-material rationality are fully integrated principles of human nature. Reality cannot be reduced to merely what scientists can weigh and measure. This simply does not match our experience. Human wisdom peaks well after the principal processes of brain building have already stopped. Loving dedication can provide a fundamental meaning for existence. None of these processes can be measured.

Aristotle said that man’s freedom resides in his rationality, a non-material power of his nature. Radical materialism always leads to determinism. Rocks cannot be free agents. But when neuroscientists reduce rationality to firing neurons, they end by asserting that man is like a rock.

Determinism is not new. The early Einstein claimed, "Man’s illusion is that he acts according to his own free will". Carl Rogers in the 1960s and B.F. Skinner in the 1970s taught that behaviour is a conditioned response to stimuli. A leading text, Fundamental Neuroscience, proclaims in its 2008 edition: "Neuroscience is a large field founded on the premise that all of behaviour and all of mental life have their origin in the structure and function of the nervous system." In other words, man is just a puppet of his circumstances.

Freedom is a touchy subject for many neuroscientists. A 2004 anthology, The New Brain Sciences, observed that neuroscientists use the word "freedom" as little as possible and usually in the last pages of their books. And on cue, Greenfield’s discussion of freedom takes half of the third last page of I.D. Basically, she suggests, apparently free thoughts are electrochemically determined.

What evidence is there that man is free?

Granted, our actions are often the result of conditioning, which has predisposed us to think or act in certain ways. For example we may try to open the front door by clicking the unlock button on the car keys. Nonetheless rationality, free choice, and personal responsibility are matters of experience.

Here are three human qualities which are evidence that we are not completely determined. Each is based on an examination of our reaction to the real world, to external and perhaps unexpected stimuli. This approach allows us to escape the accusation that actions are based on genes or our own experience or environment.

Altruism is a powerful argument. Mothers are capable of offering their lives for children yet unborn. Man is the only animal capable of making choices against the instinctive desire for self-preservation; it must be freedom of choice that gives him this capacity.

Obedience also suggests that we are self-determined. Ironically, submitting one’s will to another is a proof of human freedom. And if neuroscientists counter that obedience is itself conditioned, how can they also say that wilfulness, the exercise of one’s will, is not free either?

Self-discipline clearly shows that we are free. Man has an amazing capacity to regulate his feelings. The sudden loss of a job or the death of a child can be accepted with equanimity and nobility. Neurons do not give a transcendent meaning to experience. The Austrian psychologist Viktor Frankl spent years in Auschwitz and afterwards wrote that men can choose meaning for their lives.

The underlying theme of ID is the perfectibility of human nature. Neuroscience "explains why we are as we are and allows us to explore how we might change and be changed". But changed to what? Surely change makes sense only if man exists in a moral framework which allows him to see which choices perfect and which degrade.

In the Nichomachean Ethics Aristotle tabled the template for the moral development of a free human being through the development of good habits, or virtues. This understanding has underpinned moral education in Western civilisation for over two millennia.

Greenfield seems unaware of this – and of the dramatic growth of virtue ethics over the past 30 years. Instead, she talks about the importance of "unambiguous, uncontested input" and of the role of repetition in "strengthening neuronal connections". All this sounds remarkably like a latter-day Aristotle. As Plutarch, another ancient Greek who knew a thing or two about education, wrote, "Character is simply strongly established habit".

But Aristotle would never have been so one-dimensional about humanity. "Sense of self is based on neuronal mappings in the brain of bodily experiences as we interact with the outside world," Greenfield writes. "Subsecond assemblies of 10s or 100s of millions of neurons lasting a fraction of a second determine depth of consciousness". Ultimately she reduces humanity to the "physico-chemical context of the brain itself".

It looks as though educators will be waiting a little longer for a synthesis of virtue ethics and neuroscience. To more effectively guide children to maturity, parents and teachers would appreciate a more accurate understanding of how young brains work. The discoveries of people like Susan Greenfield have much to offer. But a science which rejects free will is flawed. Every parent knows that their most important and most difficult job is to teach their children how to use their freedom properly.