In the psychology of human behavior, denialism is a person's choice to deny reality as a way to avoid believing in a psychologically uncomfortable truth.[1] Denialism is an essentially irrational action that withholds the validation of a historical experience or event when a person refuses to accept an empirically verifiable reality.[2]
In the sciences, denialism is the rejection of basic facts and concepts that are undisputed, well-supported parts of the scientific consensus on a subject, in favor of ideas that are radical, controversial, or fabricated.[3] The terms Holocaust denial and AIDS denialism describe the denial of the facts and the reality of the subject matters,[4] and the term climate change denial describes denial of the scientific consensus that the climate change of planet Earth is a real and occurring event primarily caused in geologically recent times by human activity.[5] The forms of denialism present the common feature of the person rejecting overwhelming evidence and trying to generate political controversy in attempts to deny the existence of consensus.[6][7]
The motivations and causes of denialism include religion, self-interest (economic, political, or financial), and defence mechanisms meant to protect the psyche of the denialist against mentally disturbing facts and ideas; such disturbance is called cognitive dissonance in psychology terms.[8][9]