Humans have developed ways to use language to deceive others and themselves. We also refuse to accept that someone else is speaking truthfully. We are all in denial, some of the time at least. Denial can be as unfathomable as the multiple ways we avoid acknowledging our weaknesses and secret desires. Since the time being, we've found clever ways to express – and conceal – our feelings. Whether it's the most sophisticated diplomatic language or the baldest lie, we've found ways to deceive. And this isn't wrong at all times. At some level, deceptions are vital if humans are to live together with civility.

As Richard Sennett has argued: “In practicing social civility, you keep silent about things you know clearly but which you should not and do not say.”

But when does this necessary private self-deception become harmful? When it becomes public dogma. In other words: when it becomes denialism.

According to an article posted on The Guardian, denialism is an expansion, an intensification of denial. At root, denial and denialism are simply a subset of the many ways humans have developed to use language to deceive others and themselves. Denial can be as simple as refusing to accept that someone else is speaking truthfully. Denial can be as unfathomable as the multiple ways we avoid acknowledging our weaknesses and secret desires.

_News

Denialism is more than just another manifestation of the humdrum intricacies of our deceptions and self-deceptions. It represents the transformation of the everyday practice of denial into a whole new way of seeing the world and – most important – a collective accomplishment. Denial is furtive and routine; denialism is combative and extraordinary. Denial hides from the truth, denialism builds a new and better truth.

In scientific contexts, the denialist can deny a cause (carbon dioxide does not cause global warming), an effect (the Earth is not warming), the association between the two (CO2 levels are rising and the Earth is warming, but not because of the carbon dioxide), the direction of the cause-and-effect relationship (carbon dioxide concentrations are increasing because the earth is warming) or the identification of the cause-and-effect relationship (other factors than greenhouse gases are causing the Earth to warm). Often denialists practice minimization (the Earth is warming, but it's not harmful) and use misplaced scepticism to give an unwarranted veneer of scientific thinking.

Denialism is dangerous. There are concrete examples out there proving denialism causing actual harm. According to the same article on The Guardian, in South Africa, President Thabo Mbeki, in office between 1999 and 2008, was influenced by AIDS denialists such as Peter Duesberg, who deny the link between HIV and AIDS (or even HIV’s existence) and cast doubt on the effectiveness of anti-retroviral drugs. Mbeki’s reluctance to implement national treatment programmes using anti-retroviral drugs has been estimated to have cost the lives of 330,000 people.

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The rejection of scientific evidence is also apparent in the popularity of creationism, with an estimated 45% of Americans in 2004 believing that God created man in his present form within the past 10,000 years. While successive judgements of the US Supreme Court have rejected the teaching of creationism as science, many American schools are cautious about discussing evolution. In the United Kingdom, some faith-based schools teach evolution and creationism as equally valid ‘faith positions’. It remains unclear how they explain the emergence of antibiotic resistance.

Elsewhere, the hand of powerful corporate interests can be seen. It took many decades for the conclusions of authoritative reports by the US Surgeon General and the British Royal College of Physicians on the harmful effects of smoking to be accepted, while even now, despite clear evidence of rapid reductions in myocardial infarctions where bans have been implemented, there are some who deny that second-hand smoke is dangerous. In large part, this was due to the efforts of the tobacco industry to deflect attention to other putative causes of smoking-related diseases, from stress to keeping pet birds. The reports of the Intergovernmental Panel on Climate Change have suffered similar attacks from commentators with links to major oil companies.

Whatever the motivation, it is important to recognize denialism when confronted with it. According to scholars Pascal Diethelm and Martin McKee, the normal academic response to an opposing argument is to engage with it, testing the strengths and weaknesses of the differing views, in the expectations that the truth will emerge through a process of debate. However, this requires that both parties obey certain ground rules, such as a willingness to look at the evidence as a whole, to reject deliberate distortions and to accept principles of logic. A meaningful discourse is impossible when one party rejects these rules. Yet it would be wrong to prevent the denialists having a voice. Instead, we argue, it is necessary to shift the debate from the subject under consideration, instead of exposing to public scrutiny the tactics they employ and identifying them publicly for what they are. An understanding of the five tactics listed above provides a useful framework for doing so.