Reasons for Irrationality

Mike Oaksford and Simon Hall, ‘On the Source of Human Irrationality’, Trends in Cognitive Sciences, 20 (2016), 336-44.

OK, I’m back. September: do your worst!

One of my favourite things at the evolutionary end of Psychology is when the researchers look at some component of our mental lives, deem it inadequate or inefficient, and then work out a reason why evolution made it so, and why in the end it’s served us well.
Oaksford and Hall explore the ‘error-prone’ nature of reasoning and decision-making. They seek to overturn the idea that what’s known as ‘System 1’ thinking (fast, ‘phylogenetically old’, instinctive, unconscious) is responsible for error whereas ‘System 2’ thinking (slow, ‘later evolved’, involving language and working memory) moderates and corrects errors. Instead, they think System 1 is basically rational, and many of our shortcomings arise from System 2, but, very importantly, ‘language also sows the seeds of error correction by moving reasoning into the social domain’.
      The big problem, they argue, is that ‘people have only imperfect access to System 1. Errors arise from inadequate interrogation of System 1, working memory limitations, and mis-description of our records of these interrogations’. Social life offers mitigation and perhaps more: ‘reasoning in groups is perhaps better than individual reasoning because it provides the opportunity to transcend our individual laziness in interrogating our underlying, rational, System 1 models’.
      And then the twist that I think is most interesting: ‘The corrective role of communication and argumentation in social groups may also have removed any selective pressure to further improve language to better communicate the results of interrogating our continuous probabilistic models of the world’.


There’s a lot underlying the rather broad points I am drawing out, much of which has been, could be, and will be, debated, so (as usual, but maybe more) I urge you towards the original piece. It made me think that (curiously, perversely, brilliantly) evolution has left the individual in need of the group to a remarkable extent. Social interaction is so advantageous that error-prone inadequacy may have been a fitter strategy than individual competence. No one’s an island, etc.
      I’ve been thinking about the ‘we’ recently (as another post describes). There are literary cases where individuals merge into groups, and achieve more as a result. In some cases this could be a pertinent comparison for what’s at stake in this essay. Instead, I am thinking about Beckett – and I’ve said before that Beckett is frequently on my mind when I am writing for this blog. As usual the reason is because Beckett shows an uncanny, off-kilter versions of human cognition in uncanny, off-kilter social contexts. In Waiting for Godot or Happy Days individuals who struggle to dredge up any coherent sense of things are subjected to a social world with no corrective capacity. The results are, as you’d expect, tragicomic.

E-mail me at rtrl100[at]

Leave a Reply

Your email address will not be published.

This site uses Akismet to reduce spam. Learn how your comment data is processed.