The paradox, named after Cretan philosopher Epimenides (circa 600 BC) goes something like this: Epimenides announces that “all Cretans are liars” but, he is himself a Cretan, therefore he is a liar. And, since he is a liar, his assertion must be untrue, consequently all Cretans are truthful.
Social scientist often used the liar’s paradox to illustrate the problem of self-reference in which we process information according to our biases. We ought to be rational, but we fall short of rationality. We consume information, not to enhance the accuracy of our opinions, but to reinforce our beliefs. This phenomenon is in full display in the political opinions expressed by columnists and media commentators.
We are self-deceived, and quite wrong about the depth of our understanding of the world. If we were to ask a random sample of people if they understand how their wristwatch works, most would respond that they do. But if we ask them for a detailed explanation of how exactly a wristwatch tells time, we are unlikely to get a thorough answer. Social scientists call this bias the Illusion of Explanatory Depth. “Most people feel they understand the world with far greater detail, coherence, and depth than they usually do” (Rozenblit and Keil). In my Cuban slang, “se la saben todas” (they know it all).
Surveys confirm that most Americans limit their readings to distilled sources and headlines. When asked for detailed explanations of say, government spending, self-knowledge drops dramatically. Our consumption of knowledge is not deep. And the most overconfident pundits are often among the most ignorant, who never feel they have to inform themselves or justify their arguments. Social psychologist David Dunning has shown that; the lowest performers on tests of logical reasoning are the most likely to overestimate their test scores.
Dan Kahan, Professor of Law at Yale, and his colleagues have done fascinating work showing how our political views corrupt our reasoning. In one study, individuals were assessed in advance as to their political views and mathematical reasoning ability. The participants were then asked to solve a problem that required interpreting the results of a fake scientific study.
In reality, there were two fake studies with the same numerical data. One study was described as measuring the effectiveness of a new cream for treating skin rashes. The other study was described as a law banning carrying concealed weapons in public. Keep in mind, that both studies were identical in data and results. Both studies presented the same information; the only difference was the description of the subject matter of the study.
