Author Information: Pascal Wagner-Egger, University of Fribourg, firstname.lastname@example.org.
Gérald Bronner, Laboratoire Interdisciplinaire des Énergies de Demain
Sylvain Delouvée, University of Rennes
Sebastien Dieguez, University of Fribourg
Nicolas Gauvrit, École Pratique des Hautes Études
Wagner-Egger, Pascal; Gérald Bronner, Sylvain Delouvée, Sebastian Dieguez, Nicolas Gauvrit. “Why ‘Healthy Conspiracy Theories’ Are (Oxy)morons: Statistical, Epistemological, and Psychological Reasons in Favor of the (Ir)Rational View.” Social Epistemology Review and Reply Collective 8, no. 3 (2019): 50-67.
Since 2016, Basham, Dentith and colleagues have, on several occasions, reacted in the Journal Social Epistemology to our call “Let’s fight conspiracy theories effectively”, published in a French daily. There, we worried about French governmental and local initiatives aimed at fighting the proliferation of conspiracy theories (CT) among youths, in a context of terrorist attacks, and subsequent ethnic and religious tensions . We once responded to their critics , and we would like here to add some additional arguments, in order to evaluate the relevance of the concept of “healthy conspiracy theories”.
From this discussion, and other debates about the nature and definition of conspiracy theories, it seems that the disagreement may be very simply put: It opposes the “healthy” view on conspiracy theories held by Basham and Dentith (and others; Basham cites Peter Knight, Gina Husting, Martin Orr, Kurtis Hagen, David Coady, Jack Bratich and Charles Pigden, plus some European social psychologists), and the “unhealthy” or “pathologizing” view held by the majority of psychologists (Viren Swami, Robert Brotherton, Jan-Willem, Van Prooijen, Karen Douglas, our team in France and Switzerland, etc.) and some sociologists (Jovan Byford, Joseph Uscinski, Véronique Campion-Vincent, Gérald Bronner, Pierre-André Taguieff, etc.) working in the field.
Healthy and Unhealthy Views on Conspiracy Theories
According to the “healthy” view, we should consider each conspiracy theory on its own merits (particularism), and not discard all of them as non-rational beliefs (generalism), given that some conspiracies have been uncovered in history (Watergate, MK-Ultra, Tuskegee experiments, etc.). Its main argument is that the conspiracy theory about US/UK Weapons of Mass Destruction (WMD) has finally been proven true. This conspiracy theory accused US and UK armies to have invaded Iraq in 2003, not as they claim because of the alleged presence of weapons of mass destruction — which were finally not found, and led the US and UK governments to recognize their “error” — but in reality, to gain control on a strategic region for oil industry.
For the “unhealthy” view, conspiracy theories are mainly false, often delusional, having negative social consequences, and favored by faulty reasoning (cognitive biases).
In this paper, we will evaluate these two positions at a (1) statistical, (2) epistemological, and (3) empirical (psychological) level. We will see how the three levels unambiguously advocate in favor of the “unhealthy” view.
The Statistical Argument
First, at the statistical level, most conspiracy theories are false. If we did not miss any other, Basham and Dentith cite only one (!) conspiracy theory that turned out to be true: the US/UK Weapons of Massive Destructions. Conspiracists and defenders of the healthy view also add some dozens of proved conspiracies (Basham & Dentith enumerate for example the beginnings of holocaust, Stalin, US army in Vietnam, the Watergate, or Litvinenko case ; We may add the MK-Ultra project, Tuskegee experiments, the Tobacco conspiracy, etc.). As Popper underlined, successful conspiracies are rare in history . Moreover, and this is a crucial point, all these proved conspiracies did not rely on preceding public conspiracy theories. They were discovered by genuine journalistic, police or judicial investigations. Thus, at best, we know very few conspiracy theories that became true.
By contrast, thousands of conspiracy theories flood books, and nowadays the internet. It would be impossible to build an exhaustive list, but let us only mention some categories: (a) from secret groups (the illuminati, the templars, the freemasons, the Jews, the communists, etc.), (b) about the death of celebrities (JFK, MLK, Lady Diana, John Lennon, Michael Jackson, etc.), and living celebrities (Barack Obama, Emmanuel Macron, Miley Cyrus, etc.), (c) after natural catastrophes (Tsunamis, earthquakes, etc.), (d) about plane crashes or disappearances, (e) after terrorist attacks, (f) about political organizations or meetings (UNO, WTO, IMF, Bilderberg group, etc.), (g) following disease outbreaks, (h) about vaccines, (i) about science and technology (moon landings, chemtrails, CERN, climate change, satellites, etc.), (j) following accidents (bridge collapse at Genoa, fires, etc.), (k) in sports, (l) about alien “visitations”, etc., etc.
Concerning for example the sole Barack Obama, Mother Jones, an independent magazine, identified more than 40 conspiracy theories organized in 5 clusters (about him being Muslim, pervert, dictator, radical leftist or Kenyan) . As another edifying example, Peter Knight’s Encyclopedia of “Conspiracy Theories in American History” is nearly two 1000 pages volumes long.
To be still more precise about the statistical argument, let us think about the numerous JFK’s assassination conspiracy theories. According to former Los Angeles District Attorney Vincent Bugliosi, no less than 42 groups, 82 assassins, and 214 people had been accused in the various conspiracy theories . For the sake of the argument, let us say that there are 50 different conspiracy theories, which is below reality. There are only two epistemic possibilities. Either the official version is true, and the fifty conspiracy theories are false, or one conspiracy is true, and the forty-nine others and the official version are false. In any case, the huge majority of conspiracy theories are false. In view of this statistical argument (one CT that turned to be true against thousands of false or at best unverified CTs), when considering all conspiracy theories to be false, we will be correct at a very close rate of 100%.
Second, at the epistemological level, the official version and the conspiracy theories are not equivalent hypotheses to consider, contrary to what conspiracist often claim. We will rely here on scientific reasoning. Such reasoning can be used to evaluate any kind of hypotheses and beliefs (paranormal beliefs, pseudo-scientific theories, etc.), including socio-historic hypotheses (such as Marxism, and thus, conspiracy theories) .
The Epistemological Arguments: Occam’s and Hanlon’s Razors, and the Burden of Proof
First, by virtue of the scientific principle of Occam’s razor, simpler hypotheses have always to be preferred to more complicated ones in order to explain any phenomenon. Considering that every conspiracy theory implies an interpretative extra step compared to their corresponding official versions, every conspiracy theory will be epistemologically more demanding than its official version counterpart. For example, to explain Diana’s death by an accident due to alcohol consumption is, whether true or false, far simpler than the explanation by a plot organized by the secret services. The assassination of a celebrity by a lone and mad person is a more parsimonious explanation than the same assassination by an alleged lone and mad person, in reality being part of a vast and covert plot including many other powerful people.
Even terrorist assaults, that Basham and Dentith describe as “official conspiracy theories”, are simpler than the “alternative conspiracy theories”: the 9/11 conspiracy theory involves an “extra” conspiracy, the (false) terrorist plot and the extra plot in order to conceal the “real” conspiracy (by Al Qaeda). It would engage far more people, and would entail far more organization than the action of a small terrorist cell. Then, the official versions are always simpler (i.e., more parsimonious) than conspiracy theories to explain any event .
Second, by virtue of the burden of proof principle, advocates of conspiracy theories must give strong reasons in order to abandon the official version. As conspiracy theories are epistemologically demanding hypotheses, they necessitate high levels of proof to be accepted (such as declassified documents, documents leaks, confessions of leaders, whistleblowers, etc.). This principle is summarized by skeptics as “extraordinary claims require extraordinary levels of proof”, a principle widely used for judging paranormal hypotheses. As they contradict the current view of science, they would be accepted only with a wide and compelling array of evidence.
Apparent incongruities in zoomed pictures, slow motion looped videos may not be taken as good reasons, or evidence, to abandon even a seemingly unsatisfying official version. These pseudo-proofs are overused by conspiracy theorists to dismiss official versions (as their only “empirical arguments”) but can often be explained by simpler causes than a conspiracy. They have been called errant data .
During the Charlie Hebdo terrorist attacks in Paris in 2015 for example, conspiracists pointed at the flak jackets worn by the people who were filming the assault from the rooftop of the building. For every spectators of the video, the presence of these flak jackets became very strange. The fact that those people wear these flak jackets was taken as a proof that the attack was planned by the authorities, and not a sudden attack from terrorists. It is well known in cognitive and social psychology that the presence of incongruities and coincidences trigger an appeal for explanations . Conspiracy hypotheses will readily fulfill this need.
In reality, the bureau of an investigative journalists’ agency was in front of Charlie Hebdo’s office. The journalists wore flak jackets used in the war zones they regularly cover. Most if not all errant data have been similarly explained, for example by the NASA about Moon landing, or in the numerous debunking arguments about the 9/11 case. Reliance on errant data, sometimes on blurred pictures or videos, or isolated testimony, is reminiscent of paranormal videos and pictures of ghosts or other strange phenomena (such as the Loch Ness pictures of the “monster”) and is of course far from a rational mode of reasoning.
Errant data must be first kept unexplained, and corroborated by other sources, in order to become a clue (but still not a proof) against the official version. A second razor has to be passed through: Hanlon’s razor, which states: “Never attribute to malice that which is adequately explained by stupidity”. This may be seen as a kind of “psychosocial” version of Occam’s razor.
Potential inconsistencies (i.e., clues, that are errant data kept unexplained) in the official version must be first explained by stupidity (error), which is more parsimonious than malice (plan). In the case of conspiracy theories, stupidity would refer to incompetence, expediency (and some add defense secrets). But even when incompetence, expediency and defense secrets may be ruled out, the presence of unexplained errant data is still insufficient to refute the official version. Let us see why.
Where Burdens of Proof Must Achieve
In science indeed, even recognized elements of disconfirming evidence (what errant data are often not, as we mentioned above) have never been sufficient to disprove a theory. As philosophers of science such as Irme Lakatos  and Thomas Kuhn  argued, contrary to a strict Popperian view, any theory or hypothesis will not be refuted by a conflicting result. The latter may be explained by ad hoc hypotheses (measurement errors, etc.), unexplained results (“anomalies”), or even ignored.
In Lakatos’ terms, every theory is always surrounded by an “ocean of anomalies”. Purely epistemic refutation of a theory by contradicting elements never happens. Contradicting results must increase and be replicated by independent researchers, but even in that case, no refutation occurs. In Thomas Kuhn’s terms, the scientific field enters in a “revolutionary” state, where original ideas are requested (scientists will turn to philosophical ideas, old theories, etc.). Revolution (i.e., refutation of the old theory) will only occur when a new paradigm is proposed, in replacement of the ancient.
In Kuhn’s relativistic account, the new paradigm is incommensurable with the ancient, and thus there is no scientific growth. But in Lakatos’ model, the new research program must explain what explains the ancient, and bring some new hypotheses, some of which having been corroborated in Popper’s sense (i.e., not having been refuted through some experimental tests). In simple terms, to be considered as false, or being disconfirmed, an old theory or hypothesis must be replaced by a new and better one.
Then, in order to refute the official version, a conspiracy theory cannot only raise (even legitimate) doubts on the official version; it must specify how and why and when the conspiracy occurred. Conspiracy theorists should not only try to find negative clues or “proofs” against the official version, but positive clues or “proofs” in favor of the conspiracy hypothesis.
In order to ascertain the less parsimonious claim of a conspiracy, conspiracists must give strong arguments (confessions, papers leaks, etc.) proving the conspiracy, and not only apparent incongruities in the official version (errant data), because once again, extraordinary claims require extraordinary level of proof. Concerning the 9/11 case, Chomsky noted that a fully covered plot had to include thousands of people in the head of various domains of administration (aviation, army, secret services, etc.), and thus was simply nearly impossible. In a nutshell, conspiracy theories, which are more exactly suspicions about the official version, must be replaced by conspiracy inquiries, as was done for example in the Watergate affair.
Note that until the day that the inquiry has reported its results, the conspiracy hypothesis has to be considered as false, and not potentially true, because everything may be considered as potentially true. In science, what is not currently proved has to be considered as false, until strong evidence leads to consider it as (temporarily) true.
The same epistemological argument has been raised by Michael Shermer against creationism and revisionism . Both creationists and revisionists repeatedly point at seemingly inconsistent or unexplained facts or details, in order to dismiss the whole theory/official history. Even if these highlighted errant data were real inconsistencies (which as for conspiracies are very often not), this would not prove that the “official version” is false (and it should first be explained by error before malice).
The opponents would have to build a new theory that explains all the known facts AND the purported inconsistencies, thus bring positive clues or proofs of their claims, what would necessitate a massive level of proof. Instead, creationists and revisionists gesticulate about (often only apparent) errant data. They have nothing more to offer, as conspiracy theorists.
The Inversion of the Burden of Proof
Note that conspiracy theorists, just as revisionists and creationists, regularly use the fallacy of the inversion of the burden of proof. Creationists and revisionists sometimes ask scientists and historians to give “proofs” of evolution and the Holocaust, whereas such “proofs” cannot exist (so refutation is always possible). In Shermer’s terms, there are a huge number of converging evidences — positive clues, and not errant data about a rival hypothesis — in favor of evolution and Holocaust, such as experimental tests, predictions with respect to evolution, and numerous official documents, confessions, testimonies with respect to the Holocaust.
Similarly, members of Reopen 9/11 associations ask defenders of the official version to prove this version, which they consider as extraordinary, with extraordinary proofs. But this is not how science works: the official version already explains a lot of (if not all) events, is supported by a considerable amount of converging evidence, but as any theory, it can never be considered as definitively true.
It may be considered as temporarily and plausibly “true”, until a more parsimonious theory explains the same data, or until a new theory is consensually viewed as explaining the same amount of data, plus some new data (thus being supported by new converging evidence) . No defender of any theory can be asked to prove that his/her theory is definitely true  . The burden of proof is obviously on the shoulders of the defenders of the new, less parsimonious, potentially revolutionary theory, and the higher the novelty — or non-parsimony —, the higher the level of proof needed.
Moreover, defenders of the official version cannot prove the absence of a given conspiracy, contrary to the defenders of the conspiracy who can — and have to — prove its presence. This is what posits the ad ignorantiam fallacy, according to which we can never prove the absence of something (such as a unicorn or extraterrestrials), contrary to its presence. For example, it is impossible to definitively prove that Lee Harvey Oswald was acting alone (as nearly every known event in his life could be related to a conspiracy), but it is in principle possible under investigation to prove that he was related to a conspiracy, with recordings or documents. Thus, the burden of proof becomes still heavier for the conspiracy theory, as it is less parsimonious and more “provable” than the official version.
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 e.g. , but note that in their other papers, they do not argue for the “healthy” view . They empirically showed that conspiracy mentality predicts a preference for alternative over biomedical therapies, which is clearly not rational ; see also , .
 Byford notes that a number of social scientists are indeed somewhere in between the “healthy” and “unhealthy” views, by considering conspiracy theories as not rational per se, but as reasonable answers to the uncertainties of the modern world, or as an interpretative and non political framework, with a playful and ironic side (e.g., Jane Parish, Martin Parker, Daniel Pipes, Timothy Melley, Marc Fenster, etc.) .
 They have empirically been shown to increase risky behaviors about AIDS , and about vaccination , , to increase skepticism about global warming and thus leading to care less about environment , , to discourage political engagement , , to diminish confidence in science and to decrease pro-social behavior . Moreover, the conspiracy theories are used in the radicalization process of terrorists . Finally, at the ideological level, “conspiracism has been the staple ingredient of discriminatory, anti-democratic and populist politics, a trademark of the rhetoric of oppressive regimes, and a faithful companion to antisemitism” (p. 144) .
 Following Keeley , we define here conspiracy theories as explanations of some historical event (or events) in terms of the significant causal agency of a relatively small group of people of persons acting in secret.
 This is what the famous social psychologist Daryl Bem  tried to produce in order to show that a human anticipation of random future events, a paranormal phenomenon, could exist. He published a study which showed the effect, and after failed replications by others, conducted a multi-laboratories replication study, whose meta-analysis confirmed the effect. But the statistical tools used has been under harsh criticism and has not yet convinced the majority of the scientific community. Proofs (or mathematical tools used) must really be indisputable in order to win acceptance.
 See Mr. Sam, French skeptical Youtuber, on the following link: https://www.youtube.com/watch?v=P97hfmIvxxQ&t=669s.
 Keeley states a similar argument for every large-scale conspiracy theory . See also .