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, alternative medicine, occult beliefs, and creation science, is part of science education and scientific literacy.
Pseudoscience can cause negative consequences in the real world. Antivaccine activists present pseudoscientific studies that falsely call into question the safety of vaccines. Homeopathic remedies with no active ingredients have been promoted as treatment for deadly diseases.
Black Hebrew Israelites, a black supremacist group in the US, typify the use of numerology from the Book of Revelation. They believe group members will comprise the 144,000 people who are saved by God in the second coming that is outlined in Revelation (7:1-17). In the Book of Revelation, John is shown a vision of 144,000 martyrs who have survived and did not submit to Satan. This number is derived from the assertion that the twelve tribes of Israel consisted of 12,000 people each.