In his most recent column, David Brooks argues that the new discoveries of neuroscience and biology have confirmed the conservative view of human nature.
Sometimes a big idea fades so imperceptibly from public consciousness you don’t even notice until it has almost disappeared. Such is the fate of the belief in natural human goodness.
This belief, most often associated with Jean-Jacques Rousseau, begins with the notion that “everything is good as it leaves the hands of the Author of things; everything degenerates in the hands of man.” Human beings are virtuous and free in their natural state. It is only corrupt institutions that make them venal. They are happy in their simplicity, but social conventions make them unwell.
Brooks then goes on to list the delusional policies based on this optimistic view of human nature, from progressive education to the advent of hippies and revolutionary bohemians.
He then points out that “the new science of human nature” (I always find this phrase rather scary; the old science of human nature has led us to some rather disastrous places) reveal that Rousseau was wrong and Hobbes was right. Life is nasty, brutish and short because we are naturally nasty and brutish:
From the content of our genes, the nature of our neurons and the lessons of evolutionary biology, it has become clear that nature is filled with competition and conflicts of interest. Humanity did not come before status contests. Status contests came before humanity, and are embedded deep in human relations. People in hunter-gatherer societies were deadly warriors, not sexually liberated pacifists. As Steven Pinker has put it, Hobbes was more right than Rousseau.
Moreover, human beings are not as pliable as the social engineers imagined. Human beings operate according to preset epigenetic rules, which dispose people to act in certain ways. We strive for dominance and undermine radical egalitarian dreams. We’re tribal and divide the world into in-groups and out-groups.
In general, I think Brooks is correct about the Rousseau/Hobbes divide.* But this isn’t exactly news. Freud, following Darwin, revealed a human mind that was much darker than the Enlightenment liked to believe. (We were evolved primates, not fallen angels.) At our center was a devious id, which needed to be repressed by a conscientious super-ego. Totems and taboos, which we got from society, kept our innate evil in check. Brooks makes it sound like we need modern neuroscience and evolutionary psychology to tell us that invading Iraq was a tragically terrible idea. But that’s nonsense: it doesn’t take an fMRI machine to realize that, as Brooks puts it, people “need a strong order-imposing state.”
So to the extent the psychological sciences reveal man as a Darwinian animal, full of the same devious instincts and desires as your typical warm-blooded creature, Brooks is right: Rousseau was wrong. But I think Brooks overlooks a much more important discovery made by modern neuroscience that has large socio-political implications: our neural plasticity. (Needless to say, plasticity is less amenable to the conservative world view.)
How is plasticity relevant to political discourse? While people do operate according “to preset epigenetic rules,” these rules are vague in their instructions. Although our genes are responsible for the gross anatomy of the brain, our plastic neurons are designed to adapt to our experiences. Like the immune system, which alters itself in response to the pathogens it actually encounters (we do not have the B-cells of our parents), the brain is constantly adapting to the particular conditions of our own life.
On the one hand, this neuroplasticity research is cause for optimism. It presents new treatments for all sorts of medical maladies, from strokes to Parkinson’s. But it also tells us something very disturbing about our society. While conservatives tend to regard poverty as primarily a cultural issue, solvable by increasing marriage rates and transitioning people to minimum wage jobs, this research suggests that the symptoms of poverty are not simply states of mind; they actually warp the mind. The truth of the matter is that our neurons are designed to reflect their circumstances, not to rise above them. As a result, the monotonous stress of living in a slum literally limits the brain. Our societal inequality leads to very real neural inequalities.
Here’s the abstract of a paper published last year by the lab of Martha Farah:
Growing up in poverty is associated with reduced cognitive achievement as measured by standardized intelligence tests, but little is known about the underlying neurocognitive systems responsible for this effect. We administered a battery of tasks designed to tax-specific neurocognitive systems to healthy low and middle SES children screened for medical history and matched for age, gender and ethnicity. Higher SES was associated with better performance on the tasks, as expected, but the SES disparity was significantly nonuniform across neurocognitive systems. Pronounced differences were found in Left perisylvian/Language and Medial temporal/Memory systems, along with significant differences in Lateral/Prefrontal/Working memory and Anterior cingulate/Cognitive control and smaller, nonsignificant differences in Occipitotemporal/Pattern vision and Parietal/Spatial cognition.
And there’s a large body of evidence from other primates to support this depressing, but not surprising, conclusion. For example, if a pregnant rhesus monkey is forced to endure stressful conditions – and poverty is stressful, especially in the ghetto – her children are born with reduced neurogenesis (the birth of new neurons), even if they never actually experience stress once born. This pre-natal trauma, just like trauma endured in infancy, has life-long implications. The offspring of monkeys stressed during pregnancy have smaller hippocampi, suffer from elevated levels of glucocorticoids and display all the classical symptoms of anxiety. Being low in a dominance hierarchy also suppresses neurogenesis. So does living in a bare environment. As a general rule of thumb, a rough life – especially a rough start to life – strongly correlates with lower levels of fresh cells and reduced dendritic connections.
So if you wanted to base your politics on neuroscience, then I think you’d have to start by funding Head Start, and investing in better inner-city education, and reforming our prisons, and doing all sorts of typically “liberal” things. You’d also probably realize that war is the most stressful thing in the world, and has lasting neural consequences, for both soldiers and civilians.
I think it’s pretty clear that modern neuroscience does not confirm the conservative world view. People aren’t perfect, but then we knew Rousseau was wrong after the French Revolution. The politically relevant discoveries of neuroscience should instead focus our attention on the biological reality of poverty and inequality. These problems don’t have easy answers – and neuroscience can’t tell us how to fix them – but recent scientific research does illuminate both the enormity and the reality of our problems.
*Before we get too depressed, it also worth noting that neuroscience has also discovered the myriad ways in which humans naturally relate to each other. From mirror neurons to our theory of mind, we are designed to sympathize with our fellow man. So the news isn’t all bleak.