Myth: Science Denialism is as Rampant Among Liberals as Among Conservatives

The outline for this post is as follows:

1. The Myth and Its Flaw
2. Context and Analysis (divided into multiple sections)
3. Posts Providing Further Information and Analysis
4. References

This is the "main version" version of this post, which means that this post lacks most of my references and citations. If you would like a more comprehensive version with all the references and citations, then please go to the "+References" version of this post.

References are cited as follows: "[#]", with "#" corresponding to the reference number given in the References section at the end of this post.

1.  The Myth and Its Flaw

Political conservatives in the United States, in comparison to liberals, remain less likely to accept the science on man-made climate change and evolution. They also trust scientists less on these topics. But left-leaning science denialism on vaccination, genetically-modified organisms (GMOs), and nuclear power balances out this right-leaning science denialism. So science denialism remains as prominent among liberals as among conservatives.

Proponents of the above myth include John Stossel, WattsUpWithThat, ClimateDepot, the Daily Show, Michael Shermer, Jared Celniker of The Decision Lab, the climate scientist Patrick T. Brown, and Chris Mooney (though Mooney no longer holds this position), among others. Ezra Klein offers a sensible rebuttal to the myth.

The myth's flaw: Liberals accept scientific claims and trust scientists at about the same, or greater, rate than conservatives on the topics of vaccination, GMOs, and nuclear power. So these examples undermine the myth's false equivalence between liberals and conservatives on science denialism.


(Section 2.1 below explains the myth further, while section 2.2 rebuts the myth. So if you want to check the myth's veracity, then reading sections 2.1 and 2.2 suffices. Supplemental sections 2.3 and 2.4 discuss the political context surrounding the myth and why many people defend the myth.)

2. Context and Analysis

Section 2.1: The myth's resorts false equivalence in response to science denialism


"Denialist" and "denier" are fairly well-defined terms in science, history, and philosophy, with AIDS denialists being one of the standard examples of a science denialist group. Science denialism involves not accepting scientific claims supported by overwhelming evidence. Even some non-technical sources note this point, though one should not rely on non-technical sources for a term's meaning within a technical discipline. But these non-technical sources show that common usage of the term "denialist" largely matches what that term means in science, history, and philosophy. For example, the Oxford Lexico dictionary defines a "denialist" as:

"A person who refuses to admit the truth of a concept or proposition that is supported by the majority of scientific or historical evidence.
‘the small minority of very vocal climate change denialists’
[as modifier] ‘the denialist view’ [1]"

Holocaust denialism is an example of denialism from the field of history. However, it represents only one type of denialism. For example, denialism occurs in fields outside of history, such as AIDS denialism being one type of science denialism. So calling someone a denialist/denier does not imply that they are a Holocaust denialist/denier, anymore than calling something a car implies that it is also a red car (ironically, a number of denialists on the field of climate science directly link their opponents to the Nazis, the Holocaust, or pedophiles). 

Thus, if one feels offended at being called a denialist/denier because it reminds one of Holocaust denialists, then one should stop being a denialist, learn to live with being a denialist, or explain why one does not meet the definition of a denialist/denier. It is not enough to simply whine about being reminded of Holocaust deniers. Terms such as "denier", "denial", etc. preceded Holocaust denialism and their meaning extends beyond it. Nor are these terms inherently religious just because some religions use them, anymore than terms such as "true," "evidence," and "reason" are inherently religious just because some religions use them. 

Denialism differs from scientific skepticism, though many denialists portray themselves as being skeptics; others readily call themselves deniers. Skeptics change their position to match the evidence, while denialists do not. Many denialists employ a number of tactics in order to avoid accepting particular evidence-based conclusions. These tactics include evading an evidence-based scientific consensus, and inventing pernicious, paranoid conspiracy theories about the scientific community in order to sow distrust of scientists. 

A conspiracist mindset, contrarianism, financial incentives, ideological commitments, and other factors can each motivate denialism. People's ideological commitments in particular can shape their beliefs about science. So, for instance, many (but not all) religious/social conservatives object to climate science on the grounds that humans cannot detrimentally affect the climate God created, or on the grounds that climate science may be associated with nature worship. This leads to a negative correlation between certain religious positions vs. environmental concern and accepting various climate science points. Figure 1 depicts this correlation, along with negative correlations between religiosity and acceptance of claims in other branches of science:

Figure 1: Results of a 2014 survey on the relationship between Americans' religiosity vs. acceptance and perception of an evidence-based scientific consensus. Light gray shading represents the 95% confidence interval [2, figure 1 on page 10].
The queries for each of the panels were as follows: (g) that humans have been causing the Earth’s climate to warm in recent years; (h) that eating a genetically modified fruit could lead to a person’s own genes being modified; (i) that the Earth’s climate has been warming in recent years; (j) that the continents on which we live have been moving their locations for millions of years; and (k) that plants produce the oxygen that we breathe [2, table 1 on page 7].
The full version of this figure is here.

Similarly, many (but not all) fiscal conservatives distrust climate science research because they think this research could be used to support regulation and environmentalism. This produces a negative correlation in the US between political conservatism vs. trusting climate scientists and accepting various scientific claims regarding climatology. The two aforementioned correlations result in an ideological controversy (in the non-expert public) on climatology, with both economic and religious/social dimensions. Industry-funded think tanks, the media, and other denialists further maintain the controversy by manufacturing more false doubt about climate science.

Controversy also surrounds other issues, such as evolutionary biology and stem cell research. Thus a negative correlation persists between acceptance of the evidence-based scientific consensus on evolution vs. political conservatism, with much of this correlation explained by religiously-motivated opposition to evolutionary theory. Conservatives also remain less likely to rely on their scientific knowledge, and scientists, when forming beliefs about stem cell research. Taken together, these examples lead to the charge that US political conservatives, or the Republican Party, are disproportionately science denialists, anti-science, misrepresenting science, contributing to a war on science, etc. In response to this charge, myth proponents claim that political liberals display more anti-science / science denialist tendencies than conservatives on other topics, such as vaccines and GMOs (genetically-modified organisms).

One might come to accept the myth because it can be comforting to think both sides in a discussion are equally flawed, and that both sides make equally valid points (bothsidesism). This idea may prevail in politics, where deference to both sides in a discussion makes political compromise easier, and makes one appear admirably neutral, instead of partisan. But reality need not need conform to this politically-motivated deference; to reject this point amounts to the fallacy of appeal to consequences or wishful thinking, in which one accepts or rejects a point because it accords or conflicts with one's desires. The example of science denialism shows that two sides in a discussion need not be on par, since science denialism lacks merit in comparison to evidence-based science. To say otherwise involves drawing a false equivalence (or false balance) between two sides in a discussion. These motivations therefore serve as an inadequate justification for the myth.


Section 2.2: Evidence against the myth's false equivalence between liberals and conservatives on science denialism


Contrary to the false equivalence offered by myth proponents, conservatives may be more likely than liberals to not accept scientists' evidence-based consensus on various scientific claims. In line with this, the myth proponents' claims largely fail with respect to GMOs, vaccines, and nuclear power, when one examines statistical trends among liberals and conservatives
{I discuss the consensus on vaccines and GMOs further in "Myth: Attributing Warming to CO2 Involves the Fallaciously Inferring Causation from a Mere Correlation", with the bracketed "Attributing" sections below indicating the corresponding sections of this blogpost}:

• With regard to vaccines: The evidence-based scientific consensus is that vaccines are generally safe, effective, and do not increase the risk of neurological conditions such autism. With respect to vaccination, liberals accept scientific claims and trust scientists at about the same, or greater, rate than conservatives, though one study disputes this point. Donald Trump's supporters in particular are more likely to view vaccinations negatively, consistent with Trump's long history of vaccine denialism {sections 2.6 and 2.7 of "Attributing"}.

• With regard to GMOs: The evidence-based scientific consensus is that the GMOs available on the market are as safe as their non-GMO counterparts. With respect to GMOs, liberals accept scientific claims and trust scientists at about the same, or greater, rate than conservatives {sections 2.4 and 2.6 of "Attributing"; another study provides some further context to this subject, however, the study's questions are too broad to be helpful in assessing myth proponents' points}.

• With regard to nuclear power: I am unsure if there is an evidence-based scientific consensus on nuclear power. And if there is a consensus, I doubt that it is as strong as the scientific consensus on vaccination, GMOs, evolution, or man-made climate change, as others have noted. Various studies present evidence on the benefits and risks of nuclear power. With respect to nuclear power, liberals trust scientists at a greater rate than conservatives.

Figure 2 illustrates some of the aforementioned points with respect to GMOs and climate change, with being a Democrat serving as proxy measure of liberalism and being a Republican serving as a proxy measure of conservatism:

Figure 2: Results of a 2014 survey on the relationship between Americans' political identification vs. acceptance and perception of an evidence-based scientific consensus. The x-axis measures partisan identification from strongly Republican (Strong R) to strongly Democratic (Strong D). Light gray shading represents the 95% confidence interval [2, figure 2 on page 12].
The queries for each of the panels were as follows: (g) that humans have been causing the Earth’s climate to warm in recent years; (h) that eating a genetically modified fruit could lead to a person’s own genes being modified; (i) that the Earth’s climate has been warming in recent years; (j) that the continents on which we live have been moving their locations for millions of years; and (k) that plants produce the oxygen that we breathe [2, table 1 on page 7].
The full version of this figure is here.

The results for the dark, solid line in panel (i) are borne out by several other studies; though American political conservatives were disproportionately more likely to not accept that Earth warmed, overall the majority of Americans accepted that Earth warmed.
One might object to panels (g) and (i) by saying that there is not an evidence-based scientific consensus that humans caused warming nor that Earth recently warmed. I rebut the former objection in "Myth: Attributing Warming to CO2 Involves the Fallaciously Inferring Causation from a Mere Correlation", and I debunk the latter objection in "Myth: No Global Warming for Two Decades". Scientists from 2015 and earlier acknowledged that Earth continued to warm.

Panels g and i of figure 2 illustrate the large divide between liberals and conservatives (as measured in terms in party identification) with respect to accepting the evidence-based scientific consensus on climate change. This divide contrasts with panel h, where there is not a large, statistically significant difference between liberals and conservatives with respect to accepting the evidence-based scientific consensus on GMOs. Figure 3 below extends this point to vaccination and nuclear power as well, in a study of New Hampshire residents (in contrast to figure 2's more national sample):

Figure 3: Results of a 2014 - 2015 telephone survey on the relationship between New Hampshire residents' political identification vs. their trust in scientists on various topics. The x-axis measures the percentage of residents who reported trusting scientists on the topic in question, while the y-axis shows their self-reported political ideology from liberal to conservative. The significance tests shown indicate a statistically significant relationship between political ideology vs. trust in scientists for each topic; the p-values of below 0.001 reflect a probability of less than 1 chance in 1,000.
The queries for each of the panels were as follows: would you say that you trust, don’t trust, or are unsure about scientists as a source of information about (A) vaccines, (B) climate change, (C) nuclear power safety, (D) evolution, (E) genetically modified organisms (GMOs). The order of “trust” and “don’t trust” choices read by interviewers was rotated to avoid bias [3, figure 4].

One can use other sources to determine what proportion of a population one needs to sample in order for one to get a representative sample of that population, to a set level of uncertainty. For example, a sample of ~1100 or more is sufficient for a representative sample of New Hampshire's population or of the USA's population, to an uncertainty of +/- 3% or 4%.

So, contrary to what myth proponents claim, science denialism on GMOs, vaccines, and nuclear power is not as disproportionately prevalent among liberals as man-made climate change denialism is among conservatives. Thus the myth fails.



If you are only concerned about whether or not the myth is accurate, then you can stop reading this post at this point, since the supplemental sections below will not focus on the myth's veracity. Instead these supplemental sections will focus on: 

• why people defend the myth
• why the myth should not be used to misrepresent all conservatives
• how science denialism affects policy stances

If these matters remain of interest to you, then feel free to continue reading.


Supplementary Section 2.3: Why the myth persists for irrational (and rational) reasons


Section 2.2 undermined myth advocates' claim that science denialism is just as prevalent on the left as on the right. So why do myth proponents defend their myth, despite the aforementioned evidence against the myth? One possibility is that myth defenders want a false equivalence / false balance between liberals and conservatives, so conservatives feel comfortable and more amenable to political compromise. Or myth proponents may wish to feel admirably neutral, instead of partisan. I rebutted these defenses in section 2.1.

Another possibility is that myth proponents confuse liberals' stance on policy with liberals' stance on science and scientists. Science denialism can affect one's policy position (as I discuss in supplementary section 2.4), but one's policy position need not be rooted in science denialism. For instance:

1. One liberal uses science denialism on GMOs to justify mandatory labeling of GMOs.
2. A different liberal accepts the evidence-based scientific consensus on GMOs, while supporting mandatory labeling of GMOs. They advocate labeling because they think people have the right to know what went into making their food, even though the liberal accepts that GMOs are safe.
3. Another social liberal who is not fiscally liberal (ex: me) opposes mandatory GMO labeling since they think mandatory labeling should not be simply based on people's desire to know, but should instead be based on evidence. So, for instance, there should not be mandatory labeling on food transported in 4-wheeled vehicles, food prepared by Jewish people or women, etc., even if some people want to know which foods have these attributes. Instead, mandatory labeling should apply to lists of ingredients, nutritional content, etc. since scientific evidence shows that these factors are relevant to people's health via mechanisms such as allergic reactants to ingredients.

So liberals might have policy differences on GMOs, vaccines, and nuclear power. But those policy disagreements are not necessarily equivalent to science denialism or distrusting scientists. Nor does this mean that liberals' policy preferences always match myth proponents' pre-conceptions, as in the three numbered examples listed above. Other examples include:

• Vaccines: Liberals may be more likely than conservatives to support vaccination for themselves and mandatory childhood vaccination, though the evidence is mixed on this point. Many health professionals also defend mandatory childhood vaccinations (with allowances for medically-based exemptions), consistent with physicians vaccinating their own children.

• GMOs: Conservatives may express more support that liberals for agricultural biotechnology, and some liberals favor labeling GM food.

• Nuclear power: Conservatives may be more likely than liberals to support building more nuclear power plants, though the evidence is mixed on this point.

In addition to conflating policy stances with science denialism, myth proponents might also defend the myth because they read other research that placed the aforementioned points in context. Conservatives, for instance, often do not extend their anti-science stance to scientific research that produces new economic innovations and inventions; instead, some research indicates conservatives are more likely than liberals to trust scientists who work in this type of research. The conservatives' anti-science stance is largely reserved for scientific research that may have implications for policy on the environment or public health. 

Some research also shows that fiscal conservatives display scientific literacy greater than that of fiscal liberals. In contrast, social conservatives (especially conservative, sectarian Christians, who make up a large portion of the conservative Republican coalition) display low levels of scientific literacy. This lower level of scientific literacy extends to both religiously-controversial topics such as the Big Bang and evolution, and scientific topics that have no obvious connection to religious ideology. And as I previously mentioned in section 2.1, religiously-influenced scientific denialism may partially explain the negative correlation in the US between political conservativism vs. accepting the evidence-based scientific consensus on topics such as evolution and man-made climate change.

These differences between socially-/religiously-motivated vs. fiscally-motivated (or libertarianism-motivated) science denialism mean that political conservatives are not a homogeneous group. Moreover, not all political conservatives resort to denialism on science, as I mentioned in section 2.1 with respect to man-made climate change. And many liberals do resort to science denialism and biased attacks on scientists, since liberals are about as likely as conservatives to have negative emotional responses to evidence they find inconvenient for their ideology (though some research shows otherwise). Myth advocates may thus defend the myth because they recognize the aforementioned points.

However, myth proponents take things too far when they move from acknowledging that some people on both sides have similar problems, to claiming that the magnitude, or prevalence, of the problem is the same on both sides. The trends I discussed in section 2.2 debunk this central myth proponent claim, by showing that science denialism for topics such as vaccines and GMOs is not as disproportionately prevalent among liberals as science denialism on evolution and man-made climate change is among conservatives. But, once again, these statistical trends should not be taken as absolute, exception-less claims about all liberals and conservatives.


Supplementary Section 2.4: Ideology motivates science denialism and science denialism affects policy


Given the discussion of ideologically-motivated science denialism is sections 2.1, 2.2, and supplemental section 2.3, one might be curious about the ramifications of this denialism. Unfortunately, ideologically-motivated science denialism affects policy, policy stances, and how ideologues approach a number of scientific topics, including 
{I discuss some of these examples further in "Myth: Attributing Warming to CO2 Involves the Fallaciously Inferring Causation from a Mere Correlation", with the bracketed "Attributing" sections below indicating the corresponding sections of this blogpost}:

• Republican President Donald Trump falsely linked vaccines to autism and claimed doctors lies about this link. This is consistent with his contrarianism on vaccination, and correlates with his supporters being more likely to view vaccination negatively {further details in: "Attributing", sections 2.6 and 2.10}.

• Many American social conservatives distorted the efficacy of condoms in limiting the spread of human papillomavirus (HPV), a group of viruses that cause cervical cancer, and herpes simplex virus (HSV). Yet condoms reduce the risk of HSV and HPV infection {further details in: "Attributing", section 2.7}.

• A number of religious and social conservatives falsely claimed that HPV vaccination would promote promiscuity and thus increase the prevalence of sexually transmitted infections. Instead HPV vaccination reduced the rate of HPV infection and the rate of cancers caused by HPV {further details in: "Attributing", section 2.7}.

• Republican Vice President Mike Pence discussed evidence on the health risks of smoking, while falsely claiming that smoking doesn't kill. Some libertarians also defended tobacco advertisements directed at children, while many conservatives and conservative organizations downplayed the real risks of smoking and second-hand smoking. Some of these same conservatives then downplayed the risks of man-made climate change {further details in: "Attributing", sections 2.5 and 2.9}.

• A number of conservatives distorted the science on the association between saturated fat and heart disease {further details in: "Attributing", section 2.1}.

• Conservative think tanks, a number conservative scientists, and industry groups distorted the science on a number of environmental topics, including ozone depletion, acid rain, and leaded products such as gasoline. Conservatives may have resorted to these distortions in order to disguise how government-facilitated policy solutions helped address these environmental problems, with sometimes mixed results , though Republican-led governments often agreed to these policy solutions anyway.

• Some libertarians misrepresented the efficacy of seat belt legislation in limiting harm from car accidents.

• Former Republican Congressman Todd Akin falsely claimed, without a basis in reputable scientific evidence, that rape-related pregnancies are unusually rare because a woman's body prevents a pregnancy following rape. Akin used this claim to undermine pro-choice arguments that defend abortion in the case of pregnancy following rape; thus Akin pursued a strategy used by some pro-life advocates for decades.

• A commentator at the Wall Street Journal, and law enforcement officials, falsely claimed a version of "Ferguson effect" existed. This effect is named in reference to police officers shooting Michael Brown in the St. Louis, Missouri. The effect involves crime rates increasing nationwide because police showed more restraint in their law enforcement, in response to people protesting against police shooting unarmed civilians such as Michael Brown. Though this nationwide effect does not manifest, public protests likely impact how police officers behave in specific cities. 

And that is not even touching on the possible relationship between ideologically-based prejudice and low scientific knowledge during earlier crises, such as the 1980s/1990s HIV/AIDS epidemic. Nor does the above list cover possible distortions on other issues, such as the effect of birth control medication on health, risk of unsafe sex, and risk of unplanned pregnancies. So plenty of other domains exist in which ideologically-motivated science denialism can run rampant and damage society. 

3. Posts Providing Further Information and Analysis

• Section 3.1 of "John Christy, Climate Models, and Long-term Tropospheric Warming"
• "Myth: Judith Curry Fully and Accurately Represents Scientific Research"

4. References

1. https://en.oxforddictionaries.com/definition/denialist
2. "It’s not my consensus: Motivated reasoning and the sources of scientific illiteracy"
3. "Conservative and liberal views of science: Does trust depend on topic?"