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Bad Beliefs: Why They Happen to Good People
This is an open access title available under the terms of a CC BY-NC-ND 4.0 International licence. It is free to read at Oxford Scholarship Online and offered as a free PDF download from OUP and selected open access locations.
Bad beliefs - beliefs that blatantly conflict with easily available evidence - are common. Large minorities of people hold that vaccines are dangerous or accept bizarre conspiracy theories, for instance. The prevalence of bad beliefs may be politically and socially important, for instance blocking effective action on climate change. Explaining why people accept bad beliefs and what can be done to make them more responsive to evidence is therefore an important project.
A common view is that bad beliefs are largely explained by widespread irrationality. This book argues that ordinary people are rational agents, and their beliefs are the result of their rational response to the evidence they're presented with. We thought they were responding badly to evidence, because we focused on the first-order evidence the evidence that directly bears on the truth of claims. We neglected the higher-order evidence, in particular evidence about who can be trusted and
what sources are reliable. Once we recognize how ubiquitous higher-order evidence is, we can see that belief formation is by and large rational.
The book argues that we should tackle bad belief by focusing as much on the higher-order evidence as the first-order evidence. The epistemic environment gives us higher-order evidence for beliefs, and we need to carefully manage that environment. The book argues that such management need not be once we recognize that managing the epistemic environment consists in management of evidence, we should recognize that such management is respectful of epistemic autonomy.
Bad beliefs - beliefs that blatantly conflict with easily available evidence - are common. Large minorities of people hold that vaccines are dangerous or accept bizarre conspiracy theories, for instance. The prevalence of bad beliefs may be politically and socially important, for instance blocking effective action on climate change. Explaining why people accept bad beliefs and what can be done to make them more responsive to evidence is therefore an important project.
A common view is that bad beliefs are largely explained by widespread irrationality. This book argues that ordinary people are rational agents, and their beliefs are the result of their rational response to the evidence they're presented with. We thought they were responding badly to evidence, because we focused on the first-order evidence the evidence that directly bears on the truth of claims. We neglected the higher-order evidence, in particular evidence about who can be trusted and
what sources are reliable. Once we recognize how ubiquitous higher-order evidence is, we can see that belief formation is by and large rational.
The book argues that we should tackle bad belief by focusing as much on the higher-order evidence as the first-order evidence. The epistemic environment gives us higher-order evidence for beliefs, and we need to carefully manage that environment. The book argues that such management need not be once we recognize that managing the epistemic environment consists in management of evidence, we should recognize that such management is respectful of epistemic autonomy.
210 pages, Kindle Edition
Published December 17, 2021
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July 22, 2026
AI TLDR: In Bad Beliefs, Neil Levy argues that humans are not inherently irrational; rather, our reliance on cognitive biases and expert consensus is a deeply rational use of "higher-order evidence" to navigate a complex world. The root of bad beliefs like climate denial isn't flawed reasoning, but an "epistemically polluted" environment that feeds us unreliable social cues. Consequently, Levy argues we should stop trying to "de-bias" individuals—as behavioral economists suggest—and instead focus on sanitizing our institutions so that our natural deference leads to the truth. However, while this structural approach to misinformation is practical, in the review I point out that entirely discarding the concept of irrationality paints a false, overly optimistic picture of a human brain that remains fundamentally imperfect.
---
The book tries to reconcile a large body of scientific knowledge into a unified whole. The main premise is to show that people aren't as irrational as portrayed by psychologists and economists. Instead, people are, rationally, guided by evidence; by higher-order evidence of experts' beliefs and cues imbedded in the environment.
Levy presents a good case for thinking that many inaccurate beliefs aren't just a profession of team allegiance, but that they also significantly influence individual's behaviour. The book's prime exemplar of a bad belief is climate change denial. The author accedes that people's opinions shift depending on circumstances – from denial to futility – but they all have a common denominator of "climate change isn't a problem that needs to be addressed".
The next part delves into cultural evolution and how individual knowledge is crucial for surviving in unfamiliar environment. We look to elders and prestigious individuals. We constantly mimic people around us.
Another piece of the puzzle that Levy presents is that most of our knowledge isn't stored in our heads. Instead, we utilize physical storage to retrieve information, and often, we just know who to ask for or which expert to trust when in doubt. We place a lot of faith into scientists for the accuracy of our beliefs, because we cannot make meaningful progress of understanding complex topic first-hand.
When we can't judge the validity of information for ourselves, we defer to others. The problem is when it's difficulty to know who is trustworthy and who isn't. The environment is "epistemically polluted": the markers of prestige are unreliable, and truth is easily lost in the sea of misinformation.
All this builds up to the end of the book, which asserts that deferring to others is rational. What's more, so-called biases like "framing" or "anchoring" are, according to Levy, rational. In an unknown environment where the first-order evidence is scarce or inaccessible, relying on higher-order evidence – like the default saving rate or positive v. negative framing – is itself another piece of evidence to take into account. Of course, it doesn't override the primary evidence, but relying on it isn't a judgement error as it's usually proclaimed.
I think the book is really valuable and I changed my view on some topics. I still, however, think that there's some merit to the idea that people are imperfect, and we shouldn't say, from now on, that we process information rationally. That would give a false impression of the real state of the world.
In the end, whether you call humans irrational or rational is just a label that doesn't change the reality much, except for different behaviour based on the inferences of this very label.
Surprisingly, it wasn't until the very last page of the book that rationality was defined: "Rationality, in its fullest sense, is, roughly, the deployment of cognition in the effective service of truth by appropriate response to the evidential content of information."
I think that the economists and psychologists who promote the idea of a limited individual cognition are comparing the human brain to a perfectly capable machine, which can process information quickly and correctly. In consequence of the brain's limitations, humans develop shortcuts and heuristics that lead to correct answers most of the time. These heuristics aren't perfect, but they were adaptive in the ancestral environment.
Levy seems to be coming from the same direction, but reaches a different conclusion. He argues that most of human behaviour can be explained as rational processing of higher-order evidence. That is, a single human brain isn't able to access and understand first-order evidence, but they can defer to experts and cues in the environment. For example, if something can be framed in positive and negative way, there's usually a reason why a particular piece of evidence is presented in such a light; it's a second-order evidence and it's rational to pay attention to it. So it's not a quirk of human reasoning, it's the core of it.
So although the semantic dispute over the nature of human reasoning may be superficial, these two approaches to human reasoning offer different pathways to solve the problem. The original proponents of biases argued for individual "de-biasing": trying to foster epistemic virtues like critical thinking and open-mindedness. Levy, on the other hand, wants to sanitise the environment: so that people can believe in scientific and government institutions. He argues nudges aren't limiting autonomy; in an epistemically unpolluted environment they serve as a higher-order evidence of the accurate belief. Not providing this information is taking away from people's autonomy, as they'll lack the full picture of the situation and get them farther from the truth.
---
The book tries to reconcile a large body of scientific knowledge into a unified whole. The main premise is to show that people aren't as irrational as portrayed by psychologists and economists. Instead, people are, rationally, guided by evidence; by higher-order evidence of experts' beliefs and cues imbedded in the environment.
Levy presents a good case for thinking that many inaccurate beliefs aren't just a profession of team allegiance, but that they also significantly influence individual's behaviour. The book's prime exemplar of a bad belief is climate change denial. The author accedes that people's opinions shift depending on circumstances – from denial to futility – but they all have a common denominator of "climate change isn't a problem that needs to be addressed".
The next part delves into cultural evolution and how individual knowledge is crucial for surviving in unfamiliar environment. We look to elders and prestigious individuals. We constantly mimic people around us.
Another piece of the puzzle that Levy presents is that most of our knowledge isn't stored in our heads. Instead, we utilize physical storage to retrieve information, and often, we just know who to ask for or which expert to trust when in doubt. We place a lot of faith into scientists for the accuracy of our beliefs, because we cannot make meaningful progress of understanding complex topic first-hand.
When we can't judge the validity of information for ourselves, we defer to others. The problem is when it's difficulty to know who is trustworthy and who isn't. The environment is "epistemically polluted": the markers of prestige are unreliable, and truth is easily lost in the sea of misinformation.
All this builds up to the end of the book, which asserts that deferring to others is rational. What's more, so-called biases like "framing" or "anchoring" are, according to Levy, rational. In an unknown environment where the first-order evidence is scarce or inaccessible, relying on higher-order evidence – like the default saving rate or positive v. negative framing – is itself another piece of evidence to take into account. Of course, it doesn't override the primary evidence, but relying on it isn't a judgement error as it's usually proclaimed.
I think the book is really valuable and I changed my view on some topics. I still, however, think that there's some merit to the idea that people are imperfect, and we shouldn't say, from now on, that we process information rationally. That would give a false impression of the real state of the world.
In the end, whether you call humans irrational or rational is just a label that doesn't change the reality much, except for different behaviour based on the inferences of this very label.
Surprisingly, it wasn't until the very last page of the book that rationality was defined: "Rationality, in its fullest sense, is, roughly, the deployment of cognition in the effective service of truth by appropriate response to the evidential content of information."
I think that the economists and psychologists who promote the idea of a limited individual cognition are comparing the human brain to a perfectly capable machine, which can process information quickly and correctly. In consequence of the brain's limitations, humans develop shortcuts and heuristics that lead to correct answers most of the time. These heuristics aren't perfect, but they were adaptive in the ancestral environment.
Levy seems to be coming from the same direction, but reaches a different conclusion. He argues that most of human behaviour can be explained as rational processing of higher-order evidence. That is, a single human brain isn't able to access and understand first-order evidence, but they can defer to experts and cues in the environment. For example, if something can be framed in positive and negative way, there's usually a reason why a particular piece of evidence is presented in such a light; it's a second-order evidence and it's rational to pay attention to it. So it's not a quirk of human reasoning, it's the core of it.
So although the semantic dispute over the nature of human reasoning may be superficial, these two approaches to human reasoning offer different pathways to solve the problem. The original proponents of biases argued for individual "de-biasing": trying to foster epistemic virtues like critical thinking and open-mindedness. Levy, on the other hand, wants to sanitise the environment: so that people can believe in scientific and government institutions. He argues nudges aren't limiting autonomy; in an epistemically unpolluted environment they serve as a higher-order evidence of the accurate belief. Not providing this information is taking away from people's autonomy, as they'll lack the full picture of the situation and get them farther from the truth.
April 4, 2025
I read briefly about Levy's perspective in the book Religion as Make-Believe. Here, Leeuwen opposed Levy's emphasis on trust and his claim that our epistemic facilities are working as they should be, and it is polluted and distorted signals that result in bad beliefs. Since Leeuwen's critique did not persuade me, I was curious to read Levy's book. Interestingly, Levy interacts with Religion as Make-Believe (which was forthcoming when Bad Beliefs was written). Anyhow, there was plenty I liked in Bad Beliefs--I do wish I had written a review closer to my finishing the book, for now, several of the details have faded from my mind. I still can recall the primary reaction and the mental wrestling that followed from certain portions of the book. I will share these here.
Almost every book of this sort (I have gone through a LOT of them) uses climate deniers as the primary test case. As I am skeptical that human activity is the primary driver of climate change, I am the epitome of someone who has bad beliefs according to Levy and practically every other author who has written on the topic in modern times. I am a threat and people like me may just be the doom of the human race.
I do like how this is a book of philosophy and that he comes at the issue in a charitable manner. His point (as I took it) is the scientific consensus strongly asserts humans are the primary cause, and we as non-experts have no justification at all to disagree on the matter--in this area, we should not doubt and not question, but instead, we are to trust and obey, as we are out of our depth. He points out how oil companies took note of Big Tabacco—who attempted to sow doubt—to show the complexities and thus keep people from taking action against smoking. When the airways are so polluted, decent people will have a harder time trusting the experts and will more likely form bad beliefs. The view hints at the necessity of censorship, like what we witnessed during COVID-19, when even a Congressmen who read a scientific paper from the floor (saying cloth masks were ineffective) was banned from YouTube for mentioning something that went against the supposed "consensus" and google sought to purge all "misinformation", much of which was later learned to be true.
I do wish Levy would acknowledge one of the major reasons people like me (who trust science in most other regards) are skeptical that humans are the primary cause of global warming. Yes, why do we who go with the “consensus” in most scientific matters fail to in this case? Might we be justified?
I trust the "consensus" except when there is a religious-like, fanatical dogma, and an inquisition of sorts against anyone who is not in lockstep. If scientists can only get funding to support the "correct" narrative, and even though causation is astronomically complex, only a limited set of explanations can even asserted, I began to have my doubts. If a heretical scientist is to critically evaluate the dogmas or to research causal explanations outside of orthodoxy, means they will be labeled and lose reputation, credibility, and funding, is it any surprise that we have a consensus? When your career depends upon agreeing with the group OR ELSE, it is human nature to agree, and it is my right to question the consensus of the experts.
When things become politicized and ideological, that is when I become cautious. Levy seems to think we MUST agree with the consensus of the experts, regardless. So, if we were living during the height of Eugenics, and the scientific consensus was that racism was real--documented and well-established FACT, then our job is to unquestionably believe that and support eugenics and racist policy. Levy also seems to be in favor of censorship against science deniers who would want to question and sow doubt. Interestingly, it was the elite Progressives who loathed all the science deniers who denied the scientific consensus before the rise of Hitler. The scientific community, many politicians, and the progressive elite wholeheartedly agreed with the racist scientific consensus and believed in eugenics. It was the conservative Christians who were science deniers, they all had "bad beliefs". Interestingly, the experts believed that racial mixing was leading to catastrophe and that eugenics was necessary to SAVE civilization; without radical action, we'd see the ruin of the human species. At this time, it was only a few loan scientists who dared to go against the consensus. Anthropologists could only get funding to prove the key tenets of racism (is it any surprise they found what they were looking for?!)
So yes, think about it, Levy seems to think ordinary people should always unquestionably believe the scientific consensus, and failure to do so is to have bad beliefs, yet at the height of Lysenkoism in Russia, the scientific consensus in the USSR rejected Mendelian genetics and enacted ludicrous notions that led to the starvation of millions. The USSR made sure anyone who spoke out against Lysenko’s science went to the Gulag (it is likely a wet dream of the Progressives today, oh how they’d love to ship off all the climate deniers to concentration camps so they can save the planet). Anyhow, if the USSR allowed for freedom of speech, some people would have likely spoken out against the scientific consensus, they would be Lysenko deniers, and would thus have BAD BELIEFS, daring to disagree with the expert consensus that was killing millions.
But honestly, would it be bad beliefs?! When science becomes ideological and politicized, and the consensus is mere groupthink, then scientists must conform to the group identity beliefs OR ELSE. In Russia, it was this or execution or the gulag, in the USA it is the inability to publish, the loss of reputation, and the ruin of your career. Anyhow, THAT is the problem. Like it or not, climate science has become politicized, it is ideological—scientists are not free to disagree or explore alternative explanations. So the left is just furious, here we have almighty science, the chief authority, yet conservatives are skeptics! Well, maybe they have a reason for skepticism!
While I do not dispute that climate change is occurring, when I investigated it, I found that even global warming alarmists (when forced to act as apologists) acknowledge that human activity is almost null compared to nature, however, their talking point is to assert (without any evidence) that humans are the spark that causes natural run-away feedback loops. I learned the entire theory rests upon this premise, and yet I tried and researched this and I learned experts don't know diddly yet, it is all speculation and they acknowledge there is a lot they do not know on the feedback loops.
So we have an extremely complex system and we humans contribute something like 0.03% to the greenhouse effect. Yet dogmatically, this 0.03 is asserted to be the absolute cause of all climate change, and not only that but it is implied that we must undermine the entirety of civilization and install draconian laws to prevent imminent human extinction. This global problem is in need of global solutions, and it is impossible to make the developed world to return to our pre-industrial past without incredible power from the Elites. Talking about a politician's dream! What is horrible, is if unexplored natural factors are causing global warming, then eliminating our 0.03 contribution (at the cost of the complete ruin of all moderation) would do nothing. Climate change would continue, but we humans in taking drastic measures could lead to the death of billions, all for nothing. Getting the cause right on this IS IMPORTANT. Dogma does not help anyone. In this case, it is extremely dangerous.
Almost every book of this sort (I have gone through a LOT of them) uses climate deniers as the primary test case. As I am skeptical that human activity is the primary driver of climate change, I am the epitome of someone who has bad beliefs according to Levy and practically every other author who has written on the topic in modern times. I am a threat and people like me may just be the doom of the human race.
I do like how this is a book of philosophy and that he comes at the issue in a charitable manner. His point (as I took it) is the scientific consensus strongly asserts humans are the primary cause, and we as non-experts have no justification at all to disagree on the matter--in this area, we should not doubt and not question, but instead, we are to trust and obey, as we are out of our depth. He points out how oil companies took note of Big Tabacco—who attempted to sow doubt—to show the complexities and thus keep people from taking action against smoking. When the airways are so polluted, decent people will have a harder time trusting the experts and will more likely form bad beliefs. The view hints at the necessity of censorship, like what we witnessed during COVID-19, when even a Congressmen who read a scientific paper from the floor (saying cloth masks were ineffective) was banned from YouTube for mentioning something that went against the supposed "consensus" and google sought to purge all "misinformation", much of which was later learned to be true.
I do wish Levy would acknowledge one of the major reasons people like me (who trust science in most other regards) are skeptical that humans are the primary cause of global warming. Yes, why do we who go with the “consensus” in most scientific matters fail to in this case? Might we be justified?
I trust the "consensus" except when there is a religious-like, fanatical dogma, and an inquisition of sorts against anyone who is not in lockstep. If scientists can only get funding to support the "correct" narrative, and even though causation is astronomically complex, only a limited set of explanations can even asserted, I began to have my doubts. If a heretical scientist is to critically evaluate the dogmas or to research causal explanations outside of orthodoxy, means they will be labeled and lose reputation, credibility, and funding, is it any surprise that we have a consensus? When your career depends upon agreeing with the group OR ELSE, it is human nature to agree, and it is my right to question the consensus of the experts.
When things become politicized and ideological, that is when I become cautious. Levy seems to think we MUST agree with the consensus of the experts, regardless. So, if we were living during the height of Eugenics, and the scientific consensus was that racism was real--documented and well-established FACT, then our job is to unquestionably believe that and support eugenics and racist policy. Levy also seems to be in favor of censorship against science deniers who would want to question and sow doubt. Interestingly, it was the elite Progressives who loathed all the science deniers who denied the scientific consensus before the rise of Hitler. The scientific community, many politicians, and the progressive elite wholeheartedly agreed with the racist scientific consensus and believed in eugenics. It was the conservative Christians who were science deniers, they all had "bad beliefs". Interestingly, the experts believed that racial mixing was leading to catastrophe and that eugenics was necessary to SAVE civilization; without radical action, we'd see the ruin of the human species. At this time, it was only a few loan scientists who dared to go against the consensus. Anthropologists could only get funding to prove the key tenets of racism (is it any surprise they found what they were looking for?!)
So yes, think about it, Levy seems to think ordinary people should always unquestionably believe the scientific consensus, and failure to do so is to have bad beliefs, yet at the height of Lysenkoism in Russia, the scientific consensus in the USSR rejected Mendelian genetics and enacted ludicrous notions that led to the starvation of millions. The USSR made sure anyone who spoke out against Lysenko’s science went to the Gulag (it is likely a wet dream of the Progressives today, oh how they’d love to ship off all the climate deniers to concentration camps so they can save the planet). Anyhow, if the USSR allowed for freedom of speech, some people would have likely spoken out against the scientific consensus, they would be Lysenko deniers, and would thus have BAD BELIEFS, daring to disagree with the expert consensus that was killing millions.
But honestly, would it be bad beliefs?! When science becomes ideological and politicized, and the consensus is mere groupthink, then scientists must conform to the group identity beliefs OR ELSE. In Russia, it was this or execution or the gulag, in the USA it is the inability to publish, the loss of reputation, and the ruin of your career. Anyhow, THAT is the problem. Like it or not, climate science has become politicized, it is ideological—scientists are not free to disagree or explore alternative explanations. So the left is just furious, here we have almighty science, the chief authority, yet conservatives are skeptics! Well, maybe they have a reason for skepticism!
While I do not dispute that climate change is occurring, when I investigated it, I found that even global warming alarmists (when forced to act as apologists) acknowledge that human activity is almost null compared to nature, however, their talking point is to assert (without any evidence) that humans are the spark that causes natural run-away feedback loops. I learned the entire theory rests upon this premise, and yet I tried and researched this and I learned experts don't know diddly yet, it is all speculation and they acknowledge there is a lot they do not know on the feedback loops.
So we have an extremely complex system and we humans contribute something like 0.03% to the greenhouse effect. Yet dogmatically, this 0.03 is asserted to be the absolute cause of all climate change, and not only that but it is implied that we must undermine the entirety of civilization and install draconian laws to prevent imminent human extinction. This global problem is in need of global solutions, and it is impossible to make the developed world to return to our pre-industrial past without incredible power from the Elites. Talking about a politician's dream! What is horrible, is if unexplored natural factors are causing global warming, then eliminating our 0.03 contribution (at the cost of the complete ruin of all moderation) would do nothing. Climate change would continue, but we humans in taking drastic measures could lead to the death of billions, all for nothing. Getting the cause right on this IS IMPORTANT. Dogma does not help anyone. In this case, it is extremely dangerous.
July 26, 2026
Bad Beliefs is an ambitious attempt to explain why otherwise reasonable—and often morally decent—people can end up holding false and sometimes harmful beliefs. One of the book's greatest strengths is that Levy resists reducing the problem to stupidity or malice. Instead, he takes seriously our cognitive dependence on others and the role that a polluted epistemic environment plays in shaping what we believe.
That said, I was not fully persuaded by one of the book's central claims. In my view, Levy does not draw a sufficiently clear distinction between instrumental rationality and epistemic rationality. The fact that relying on other people and on socially distributed knowledge is often efficient, practical, or even unavoidable does not by itself show that these practices are epistemically justified or truth-conducive. A strategy can be highly useful for navigating everyday life without necessarily being a reliable route to the truth.
I was also unconvinced by the arguments for some of Levy's proposed remedies—particularly epistemic environmental engineering, nudging, and limiting the platforms available to certain views. Rather than resolving the problem, these proposals raise difficult questions about epistemic paternalism and who gets to decide which ideas deserve to be heard.
Overall, this is an important, thought-provoking, and highly worthwhile book. Even if one remains unconvinced by some of its conclusions and recommendations, it succeeds in provoking serious reflection on how beliefs are formed and sustained.
That said, I was not fully persuaded by one of the book's central claims. In my view, Levy does not draw a sufficiently clear distinction between instrumental rationality and epistemic rationality. The fact that relying on other people and on socially distributed knowledge is often efficient, practical, or even unavoidable does not by itself show that these practices are epistemically justified or truth-conducive. A strategy can be highly useful for navigating everyday life without necessarily being a reliable route to the truth.
I was also unconvinced by the arguments for some of Levy's proposed remedies—particularly epistemic environmental engineering, nudging, and limiting the platforms available to certain views. Rather than resolving the problem, these proposals raise difficult questions about epistemic paternalism and who gets to decide which ideas deserve to be heard.
Overall, this is an important, thought-provoking, and highly worthwhile book. Even if one remains unconvinced by some of its conclusions and recommendations, it succeeds in provoking serious reflection on how beliefs are formed and sustained.
July 27, 2023
A riveting view on the importance of distributed epistemic labor.
Humans as social and cultural agents rely heavily on the peers, experts, and in general higher-order evidence as a means to scaffold cognition.
This comes as an evolutionary advantage while the caveats remain as made more noticeable in modern parlance as various forms of epistemic pollution. The book in parts downplays these downsides albeit presenting some solutions to decontaminate these aberrant takes and misinformation. Nevertheless, I agree with the overall idea.
Humans as social and cultural agents rely heavily on the peers, experts, and in general higher-order evidence as a means to scaffold cognition.
This comes as an evolutionary advantage while the caveats remain as made more noticeable in modern parlance as various forms of epistemic pollution. The book in parts downplays these downsides albeit presenting some solutions to decontaminate these aberrant takes and misinformation. Nevertheless, I agree with the overall idea.
October 18, 2025
It reads pleasantly for a philosophy book, with interesting ideas, but that is partially due to it all remaining somewhat superficial. Some of the proposals, outsourcing beliefs in particular, lead to much more complications than is pretended here. They need more detail and argument. It occasionally read more like public rather than academic philosophy.
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