One
of the other most important things we’ve learned in the past 20-30 years about
humans as political thinkers is just how much the left and right are
genetically predisposed to their beliefs. In other words, when someone annoys
you with their dodgy, ill-conceived political opinions, seek solace in the fact
that they often can’t help it, because a significant part of what they think is
likely to be ingrained in their mental hardware.
Our moral judgments arise from a set of psychological foundations shaped by evolution to help us thrive in social settings – and there is strong evidence that left and right wing adherents tend to prioritise these moral foundations differently. I said in a recent blog post that leftists tend to more strongly emphasise values like care/harm and fairness/reciprocity, while conservatives consider a broader array of moral considerations - adding loyalty, authority, and sanctity to their core concerns. And personality traits, such as openness to experience and conscientiousness, are partly heritable, and they also correlate with political orientation. Openness to experience is associated with liberal or left-leaning views, and conscientiousness is associated with conservative or right-leaning views. This is especially backed up by twin studies, which have shown that identical twins (who share the same genes, of course) are more likely to have similar political views compared to fraternal twins, who share only about half their genes (I say ‘around half” because the specific combination of DNA inherited by each sibling is random, which leads to slight variations around the 50% average). These findings suggest that genetics potentially accounts for around 30-40% of the variation in political attitudes, with environmental and cultural factors (like upbringing, life experiences, and social influences) making up the majority of the rest of the percentage.
Don’t get me wrong, political beliefs are not fixed and unchangeable – there is a complex interplay between genes and environment – and all dubious political views have the potential to be revised with better reasoning and stronger empirical analysis. But, given that we know that these differences in moral priorities appear to have a heritable component, where genetics predisposes people to certain orientations and beliefs, it ought to make us wiser in how we discuss politics – and also encourage us to take the political rants we see with a huge dose of salt. In fact, when we see our friends waxing lyrical about politics and social justice online, perhaps we can amuse ourselves with the thought that they may have a degree of limited control over these views like they do limited control over preferences for spicy food or their fear of heights.
