Crackpot theory

Pseudoscience consists of statements, beliefs, or practices that are claimed to be both scientific and factual, but are incompatible with the scientific method. Pseudoscience is often characterized by contradictory, exaggerated or unfalsifiable claims; reliance on confirmation bias rather than rigorous attempts at refutation; lack of openness to evaluation by other experts; and absence of systematic practices when developing theories, and continued adherence long after they have been experimentally discredited. The term pseudoscience is considered pejorative because it suggests something is being presented as science inaccurately or even deceptively. Those described as practicing or advocating pseudoscience often dispute the characterization.

The demarcation between science and pseudoscience has philosophical and scientific implications. Differentiating science from pseudoscience has practical implications in the case of health care, expert testimony, environmental policies, and science education. Distinguishing scientific facts and theories from pseudoscientific beliefs, such as those found in astrology, alchemy, medical quackery, occult beliefs, and creation science, is part of science education and scientific literacy.

Apart from theoretical issues, pseudoscience can cause severe negative consequences in the real world. For example, antivaccine activists present pseudoscientific studies that falsely claim that the science on the safety of vaccines is uncertain, which has led to many deaths. Homeopathic remedies with no active ingredients have been promoted for deadly diseases such as malaria, and rhinoceros horn is falsely sold as effective treatment, pushing rhinos to the very brink of extinction.

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