Defining and recognizing
The Hoofnagle brothers, a lawyer and a physiologist from the United States, who have done much to develop the concept of denialism, have defined it as the employment of rhetorical arguments to give the appearance of legitimate debate where there is none,5 an approach that has the ultimate goal of rejecting a proposition on which a scientific consensus exists.6 In this viewpoint, we argue that public health scientists should be aware of the features of denialism and be able to recognize and confront it.Denialism is a process that employs some or all of five characteristicelements in a concerted way. The first is the identification of conspiracies.
When the overwhelming body of scientific opinion believes that something is true, it is argued that this is not because those scientists have independently studied the evidence and reached the same conclusion. It is because they have engaged in a complex and secretive conspiracy. The peer review process is seen as a tool by which the conspirators suppress dissent, rather than as a means of weeding out papers and grant applications unsupported by evidence or lacking logical thought. The view of General Jack D Ripper that fluoridation was a Soviet plot to poison American drinking water in Dr Strangelove, Kubrick’s black comedy about the Cold War is no less bizarre than those expressed in many of the websites that oppose this measure......
.......The second is the use of fake experts.
These are individuals who purport to be experts in a particular area but whose views are entirely inconsistent with established knowledge. They have been used extensively by the tobacco industry since 1974, when a senior executive with R J Reynolds devised a system to score scientists working on tobacco in relation to the extent to which they were supportive of the industry’s position. The industry embraced this concept enthusiastically in the 1980s when a senior executive from Philip Morris developed a strategy to recruit such scientists (referring to them as ‘Whitecoats’) to help counteract the growing evidence
on the harmful effects of second-hand smoke. This activity was largely undertaken
through front organizations whose links with the tobacco industry were concealed, but under the direction of law firms acting on behalf of the tobacco industry.10 In some countries, such as Germany, the industry created complex and influential networks, allowing it to delay the implementation of tobacco control policies for many years.11 In 1998, the American Petroleum Institute developed a Global Climate Science Communications Plan, involving the recruitment of ‘scientists who share the industry’s views of climate science [who can] help convince journalists, politicians and the public
that the risk of global warming is too uncertain to justify controls on greenhouse
......The third characteristic is selectivity, drawing on isolated papers that challenge
the dominant consensus or highlighting the flaws in the weakest papers among those that support it as a means of discrediting the entire field.
An example of the former is the much cited Lancet paper describing intestinal abnormalities in 12 children with autism, which merely suggested a possible link with immunization against
measles, mumps and rubella.19 This has been used extensively by campaigners against immunization, even though 10 of the paper’s 13 authors subsequently retracted the suggestion of an association. 20 Fortunately, the work of the Cochrane Collaboration in promoting systematic reviews has made selective citation easier to detect.
Another is a paper published by the British Medical Journal in 2003,21 later shown to suffer from major flaws, including a failure to report competing interests,22 that concluded that exposure to tobacco smoke does not increase the risk of lung cancer and heart disease.
This paper has been cited extensively by those who deny that passive smoking has any health effects, with the company Japan Tobacco International still quoting it as justification for rejecting ‘the claim that ETS is a cause of lung cancer, heart disease and chronic pulmonary diseases in non-smokers’ as late as the end of 2008.23 Denialists are usually not deterred by the extreme isolation of their theories, but rather see it as the ndication of their intellectual courage against the dominant orthodoxy and the accompanying political correctness, often comparing themselves to Galileo.
The fourth is the creation of impossible expectations of what research can deliver.
For example, those denying the reality of climate change point to the absence of accurate temperature records from before the invention of the thermometer. Others use the intrinsic
uncertainty of mathematical models to reject them entirely as a means of understanding a phenomenon.
The fifth is the use of misrepresentation and logical fallacies.
For example, pro-smoking groups have often used the fact that Hitler supported some antismoking
campaigns to represent those advocating tobacco control as Nazis (even coining the term nico-nazis),26 even though other senior Nazis were smokers, blocking attempts to disseminate anti-smoking propaganda and ensuring that troops has sufficient supplies of cigarettes.27 Logical fallacies include the use of red herrings, or deliberate attempts to change the argument and straw men, where the opposing argument is misrepresented to make it easier to refute. For example, the US Environmental Protection Agency (EPA) determined in 1992 that environmental tobacco smoke (ETS) is carcinogenic, a finding confirmed by many other authoritative national and international public health institutions.
The EPA assessment was described by two commentators as an ‘attempt to institutionalize a particular irrational view of the world as the only legitimate perspective, and to replace rationality with dogma as the legitimate basis of public policy’, which they labelled as
nothing less than a ‘threat to the very core of democratic values and democratic
public policy’.28 Other fallacies used by denialists are false analogy, exemplified by the argument against evolution that, as the universe and a watch are both extremely complex,
the universe must have been created by the equivalent of a watchmaker and the excluded middle fallacy (either passive smoking causes a wide range of specified diseases or causes none at all, so doubt about an association with one disease, such as breast cancer, is regarded as sufficient to reject an association with any disease)