Superforecasting: The Art and Science of Prediction

In the sixth century BCE (before the Common Era), the Greek lyric poet Archilochus wrote, “The fox knows many things but the hedgehog knows one big thing” (69). Archilochus remained silent on whether hedgehogs or foxes fared better, but in the 1953 essay “The Hedgehog and the Fox,” 20th-century philosopher Isaiah Berlin preferred foxes. While hedgehogs regard life through a singular big idea, foxes draw upon a multiplicity of experiences to deliver their life’s work. A typical hedgehog from history might be the ancient Greek philosopher Plato, with his world of ideals, while a fox would be the 16th-century British playwright William Shakespeare. While Tetlock claims to have no preference between hedgehogs and foxes, he enjoys the metaphor because “it captured something deep in my data” when he found that big-idea experts were more like hedgehogs, while more open-minded equivocal thinkers with an interest in many topics were foxes (69).

Tetlock’s view is that the media prefers to feature hedgehogs rather than foxes. The former, with their controversial views and consistent opinions, become like beloved, if stereotypical, sitcom characters. Even if they keep spouting a “truth” that is inconsistent with current reality, their constancy of opinion has a lulling effect on the audience. Tetlock shows how “prototypic hedgehog” Larry Kudlow, a Republican political commentator and financial analyst, was able to recover from maintaining that his big idea (supply-side economics) was triumphing during George W. Bush’s presidency despite growing evidence to the contrary (69). According to Tetlock, Kudlow was able to peddle this delusion (perhaps even to himself) because supply-side economics was “the Big Idea he uses over and over when trying to figure out what will happen next” and is akin to green-tinted glasses that cause the wearer to perceive the world with a verdant hue (71). People with Kudlow’s predilection for seeing the world through the distorted lens of their main idea do not make good forecasters, regardless of political persuasion. This is because the more they know on a topic, the less they are willing to test their hypotheses against counterarguments and new information. However, while they would never make it as a GJP superforecaster, hedgehogs in the media often recover quickly from their misleading predictions given “the inverse correlation between fame and accuracy”; Tetlock’s research found that the “the more famous an expert was, the less accurate he was” (72). Hedgehogs’ less accurate predictions often make better stories because they omit the troubling, contradictory nuance of reality. Hedgehogs can be very persuasive, adding on logical-seeming reasons about why they are right without considering other perspectives. This panders to the human evolutionary fear of uncertainty and the System 1 thinking that favors snap judgments to quickly identify predators in the shadows.

Foxes, in contrast, with their multiple perspectives and ambivalence, are less compelling media personalities. Their stories are layered, complex, and often contradictory in a way that is unsatisfying and even unsettling to audiences. However, while “the aggregation of many perspectives is bad TV […] it’s good forecasting” (72). In his book, Tetlock aims to overcome the media’s negativity toward foxes by painting attractive portraits of these mavericks, who have overcome difficulties, have many interests, and remain youthfully curious and open-minded. For example, Tetlock describes fox-natured superforecaster Devyn Duffy as “a fantastic updater,” implying that his main intellectual attribute is versatility and growth (153). For example, Duffy became a superforecaster with the GJP after being laid off from his Pittsburgh factory job, and he adapted quickly. He exhibits Carol Dweck’s notion of the growth mindset—a characteristic that, the authors claim, is more typical of foxes than hedgehogs, chiefly because foxes believe intelligence is mutable rather than fixed. This gives them an advantage in making predictions about a changing world. However, foxes also need to be humble and aware that they may stumble into the illusion of unassailable expertise. Superforecaster Jean-Pierre Beugoms, for example, who is knowledgeable about military matters, knows that he must exercise extra caution on this topic so that he does not fall into hubris. To keep forecasting accurately, he must be open-minded about the world and his own limitations.

Throughout the book, the authors argue that as we learn to appreciate uncertainty and consider views that oppose our own, we will come to revere the fox as much as the hedgehog. During this journey, we will learn the value of complexity, curiosity, and humility rather than big personalities and easy answers. However, at the end, the authors acknowledge that hedgehogs have their role in being superquestioners, as their propensity for confidently tackling big ideas can set the agenda for superforecasters’ investigations. Thus, the dream team would be made up of both foxes and hedgehogs.