by Yohan J. John
Human decision-making routinely confounds our attempts at understanding. Right now, the western world is in a state of bafflement and anxiety brought on by unprecedented collective decisions. From the British public's vote to leave the European Union to Republican voters' selection of Donald Trump as their presidential candidate, the past month or so has been a vivid illustration of the unpredictability of human choice.
There is a temptation, particularly among elites who see themselves as well-educated, to see Brexit and the rise of Trump as a failure of intelligence. According to this perspective, disgruntled working class voters are stupid: willfully ignoring the “facts” offered to them by the experts. (Michael Gove has surely captured the spirit of the era with the statement: “People in this country have had enough of experts”.) There may be some truth in the Stupidity Hypothesis, but a far more interesting thing to think about is how statements come to be seen as relevant facts in the first place. And perhaps even more fundamentally, how exactly do facts influence our decisions?
What I would like to say about decision-making strikes me as both obvious and easy to miss. The process of arriving at a decision necessarily involves ignoring information. However much information is available beforehand, at the time a decision is made, much of it is effectively disregarded. And this is not just true of democratic decisions, for which the opinions of the losing side have little or no direct effect on subsequent events. Whenever a situation involves multiple facets, the process of deciding on a course of action involves a simplification that must abstract away from the initial complexity. From a mathematical perspective, decision-making is the process of collapsing a high-dimensional system into a one-dimensional system.
