The first thing that strikes me when I visit Alex in her supported accommodation is the huge lock on the kitchen door. The accessible rooms are devoid of any food or drink, the exception being two dispensers of sugar-free squash in the living room. Even the food-waste bin outside the back door is padlocked. Packages delivered to the home’s residents are opened in front of staff and searched for surreptitiously ordered food. These extraordinary efforts are crucial to prevent the housemates from eating too much.
For Alex and her fellow residents, their perpetual and insatiable hunger is not a matter of gluttony. It is not a marker of immorality, or depravity of the soul. It is a function of their biology. All those living in that house have a rare genetic disorder, Prader-Willi syndrome, which affects the region of the brain that controls appetite and hunger. For them, the signal to stop eating never materialises. People with this condition are destined never to feel full, sometimes even eating non-food items in the search for satiety. So extreme is their hunger that occasionally they will overeat to the point that they die of a perforated stomach, or choke on regurgitated food.
In fact, for each of the behaviours defined as the seven deadly sins by Pope Gregory I in AD590, and immortalised in the public mind in Dante’s Divine Comedy, there are countless examples where the cause is obviously overwhelmingly biological. Medications for Parkinson’s disease inducing extreme sexual desire, for instance, or even a change in sexual preference. Brain tumours or degenerative neurological diseases generating sloth or pride. For wrath, there are families with a mutation in a gene sometimes termed the “warrior gene”, where males are extremely prone to aggression and violence.
For these individuals, it is clear that their “sinful” behaviour is not entirely within their control. A determinable medical condition largely explains why they are the way they are. These cases clearly illustrate that a change in the structure or function of our brains can result in a change in our actions or personalities. And, by extension, that these aspects of humanity are determined by the neurological machinery within.
The seven deadly sins are woven into the tapestry of what it is to be human, and for good reason. Each of these tendencies, at least in moderation or in specific circumstances, can be seen as a tool for survival. They are propelled by evolutionary imperatives. Without lust, we are destined not to reproduce, to become extinct. Greed and gluttony promote the accumulation of physical possessions or calories, a safeguard against less plentiful times. Sloth balances energy expenditure against potential reward. But it is when these behaviours are excessive or inappropriate that they result in harm.
We are all somewhere on the spectrum of every one of these traits. Even for those of us with healthy brains, however, untouched by disease or disorder, there are factors beyond our control that influence that nature of who and what we are.
Many of these determinants are present from conception: genes inherited from our parents that will influence our appetite and adult bodyweight. Common variants in the so-called warrior gene that affect our levels of aggression in later life have even been used in sentence mitigation for violent crimes such as murder.
Other factors can affect our brain’s development while we are still in the womb. Exposure to testosterone while our brains grow affects aggression levels in later life; comparing the length of your index finger to your ring finger provides a measure of testosterone exposure in utero. Studies of people born after the famine in the Netherlands of 1944-45 demonstrated that those exposed to starvation in the early part of pregnancy were more likely to be obese adults, with the associated medical complications.
Even after birth, our brains are rendered pliable by our environment. Exposure to a stressful or traumatic upbringing can alter the development of those structures of the brain that regulate the generation and reining in of emotions such as anger and fear. Our parenting style can fuel our children’s self-esteem, but also their levels of narcissism, a form of pride.
It might be argued that there is a clear distinction between those who are not “normal” or “healthy” and the rest of us. For those with clear neurological disease, they have little or limited control over their nature, while the rest of us have free will – the ability to choose, to act in one way or another – despite the many factors outside our own control. But the dividing line between what constitutes disorders of the body or brain and disorders of the “soul” is not static. In the past, many of those behaviours I describe would have not been deemed to have medical causes. With advances in medical technology, more people have a demonstrable physical cause.
So, at what point does normal end and pathological begin? When do all these intrinsic and environmental factors that shape the structure and function of our brains constitute a sufficiently heavy burden to rob us of the capacity to exert free will?
There remains no consensus among scientists or philosophers on the nature of free will, whether we all have it or if it is illusory. In all likelihood, as with the essence of the seven sins, our degree of free will sits on a spectrum, too. For the moment, however, who should be the arbiter of the lines between the normal and the pathological, the biological and the moral? Is it the physician, the scientist, the judge, the philosopher or the priest?
