Denialism

Denialism is choosing to deny reality as a way to avoid an uncomfortable truth. Author Paul O'Shea remarks, " is the refusal to accept an empirically verifiable reality. It is an essentially irrational action that withholds validation of a historical experience or event".

In science, denialism has been defined as the rejection of basic concepts that are undisputed and well-supported parts of the scientific consensus on a topic in favor of ideas that are both radical and controversial. It has been proposed that the various forms of denialism have the common feature of the rejection of overwhelming evidence and the generation of a controversy through attempts to deny that a consensus exists.

The terms Holocaust denialism and AIDS denialism have been used, and the term climate change denialists has been applied to those who argue against the scientific consensus that global warming is occurring and that human activity is its primary cause. Use of the word denialism has been criticised, for example as a polemical propaganda tool to suppress non-mainstream views. Similarly, in an essay discussing the general importance of skepticism, Clive James objected to the use of the word denialist to describe climate change skeptics, stating that it "calls up the spectacle of a fanatic denying the Holocaust." Celia Farber has objected to the term AIDS denialists arguing that it is unjustifiable to place this belief on the same moral level with the Nazi crimes against humanity. However, Robert Gallo et al. defended this latter comparison, stating that AIDS denialism is similar to Holocaust denial as it is a form of pseudoscience that "contradicts an immense body of research."

Several motivations for denialism have been proposed, including religious beliefs and self-interest, or as a psychological defense mechanism against disturbing ideas.