When experts and laymen disagree, the rational default presumption is that the expert is probably right—a presumption we rely on for mechanics, doctors, and historians—though it is only a starting point that can be overridden by a specific, testable account of expert bias.

An individual vote is almost never decisive—with a hundred million voters the chance your vote breaks a tie is like being struck by lightning—so the personal incentive to vote wisely is essentially zero, just as a single Cairo driver's emissions barely affect air quality.

Anti-market bias is the public's tendency to infer that because market participants have self-interested (greedy) intentions, the social consequences must be bad—whereas economists argue that competition and the freedom of customers to go elsewhere channel self-interest into serving others.

Betting (prediction) markets would aggregate dispersed knowledge far better than surveys for questions like how much living standards have improved, because the uninformed self-select out and well-informed participants stake large sums whenever the odds drift from the truth.

Voters often treat the mere passage of legislation as a 'result' rather than the actual outcome (e.g. counting passing a gun-control bill as success regardless of whether the murder rate falls), so political accountability for genuine outcomes is weaker than it appears.

People exert more intellectual discipline and stay open-minded on questions where being wrong is personally costly (a drunk surgeon who believes he operates well will quickly ruin his career), but on questions where their belief has no personal cost—like how voting affects national policy—they indulge comforting irrationality.

Farm subsidies enjoy roughly equal support in farm states and non-farm states, contradicting the self-interest explanation, because non-farmers believe subsidies are necessary to ensure a stable food supply.

Anti-foreign bias has an evolutionary basis: in ancestral small-tribe conditions encountering another tribe was often genuinely zero-sum (competing over fixed game) or dangerous (violence), so wariness of foreigners was adaptive—but this instinct now misfires onto harmless modern trade (e.g. the Toyota dealership).

Most of the improvement in the living standards of the poorest members of society over a century or two comes from the growth and broad availability of production, not from forced redistribution; even equally dividing the entire output of the 19th-century economy (assuming no incentive effects) would leave everyone poor by modern standards.

Pessimistic bias is the public's tendency to underestimate how well the economy is doing and overestimate decline relative to economists; this bias has good US data but, unlike the other three, is less clearly cross-cultural or stable over time.

The two common theories of why economists are biased—self-serving bias (they are rich, white, male, tenured) and ideological bias (they are conservative Republicans)—both fail empirically: controlling for income, job security, gender, race and income growth closes only ~18% of the belief gap (often with signs in the wrong direction), and the typical economist is actually a moderate Democrat who nonetheless thinks downsizing helps the economy and supply-and-demand sets prices.

Because voters partly evaluate politicians on the policies they favor (not just on results), the more competitive the political race, the more reliably politicians deliver the policies voters want—so persistently mistaken voter beliefs persistently produce bad policies, since favoring those policies is what it takes to get elected.

Complexity of the world cannot by itself explain persistent biased beliefs, because complexity should rationally produce agnosticism (suspended judgment); instead people who haven't studied economics hold confident, vehement views that gravitate precisely toward the answers textbooks say are wrong.

Politics functions as the religion of modernity: the passion and dogmatism once reserved for religion are now transferred to political beliefs, so questioning someone's key political views provokes hostility rather than curiosity—and treating contrary evidence as an enemy ('killing the messenger') is a poor route to truth.

The standard public-choice explanation for bad policies—that concentrated special interests hijack the political process while diffuse losers stay rationally ignorant—is largely wrong, because policies like steel tariffs are extremely popular with the general public, not snuck past them.

Democracy works surprisingly well in that politicians genuinely deliver what voters want; the problem is that what voters want is often detrimental to their own welfare.

People resist economic arguments not because of lack of exposure but because holding mainstream beliefs provides psychological benefits—comfort, social belonging—so challenging a shared worldview is painful, illustrated by an economist whose picnic companions physically edged away after he questioned the minimum wage.

The same economic biases recur across centuries and countries (visible in Bastiat in 1840s France, Adam Smith in 1700s England, and Böhm-Bawerk on ancient Israelite attitudes toward interest), which suggests a biological or evolutionary-psychological origin rather than mere local culture.

Make-work bias is judging the economy by employment rather than production; by the employment standard 19th-century America (with grueling all-day labor) would rank above the modern economy, yet living standards were miserable—so trade and technology that reduce employment can still make society wealthier.

Voter irrationality functions as political pollution—a negative externality: one person's biased vote barely shifts the election, but when millions vote on their biases, society gets bad policy 'by popular demand,' with each individual gaining a private psychological benefit while imposing small costs on hundreds of millions of others.