Pseudoscience consists of statements, beliefs, or practices that are claimed to be both scientific and factual, but are incompatible with the scientific method.[1][Note 1] 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[4] because it suggests something is being presented as science inaccurately or even deceptively. Those described as practicing or advocating pseudoscience often dispute the characterization.[2]

The demarcation between science and pseudoscience has philosophical and scientific implications.[5] Differentiating science from pseudoscience has practical implications in the case of health care, expert testimony, environmental policies, and science education.[6] Distinguishing scientific facts and theories from pseudoscientific beliefs, such as those found in astrology, alchemy, alternative medicine, occult beliefs, religious beliefs, and creation science, is part of science education and scientific literacy.[6][7]

Pseudoscience can be harmful. 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.


The word pseudoscience is derived from the Greek root pseudo meaning false[8][9] and the English word science, from the Latin word scientia, meaning "knowledge". Although the term has been in use since at least the late 18th century (e.g. in 1796 by James Pettit Andrews in reference to alchemy[10][11]) the concept of pseudoscience as distinct from real or proper science seems to have become more widespread during the mid-19th century. Among the earliest uses of "pseudo-science" was in an 1844 article in the Northern Journal of Medicine, issue 387:

That opposite kind of innovation which pronounces what has been recognized as a branch of science, to have been a pseudo-science, composed merely of so-called facts, connected together by misapprehensions under the disguise of principles.

An earlier use of the term was in 1843 by the French physiologist François Magendie, that refers to phrenology as "a pseudo-science of the present day".[12][13] During the 20th century, the word was used pejoratively to describe explanations of phenomena which were claimed to be scientific, but which were not in fact supported by reliable experimental evidence. From time-to-time, though, the usage of the word occurred in a more formal, technical manner in response to a perceived threat to individual and institutional security in a social and cultural setting.[14]

Other Languages
Afrikaans: Pseudowetenskap
العربية: علم زائف
asturianu: Pseudociencia
azərbaycanca: Yalan elmlər
Bân-lâm-gú: Gî-sū kho-ha̍k
беларуская: Псеўданавука
български: Псевдонаука
bosanski: Pseudonauka
čeština: Pseudověda
Ελληνικά: Ψευδοεπιστήμη
español: Pseudociencia
Esperanto: Pseŭdoscienco
euskara: Sasizientzia
فارسی: شبه‌علم
føroyskt: Pseudovísindi
français: Pseudoscience
한국어: 의사과학
hrvatski: Pseudoznanost
Bahasa Indonesia: Ilmu semu
interlingua: Pseudoscientia
íslenska: Hjáfræði
italiano: Pseudoscienza
latviešu: Pseidozinātne
lietuvių: Pseudomokslas
Lingua Franca Nova: Pseudosiensa
magyar: Áltudomány
Bahasa Melayu: Pseudosains
Nederlands: Pseudowetenschap
日本語: 疑似科学
norsk nynorsk: Pseudovitskap
oʻzbekcha/ўзбекча: Soxta fan
polski: Pseudonauka
português: Pseudociência
русиньскый: Псевдонаука
русский: Псевдонаука
Simple English: Pseudoscience
slovenčina: Pseudoveda
slovenščina: Psevdoznanost
کوردی: زڕزانست
српски / srpski: Псеудонаука
srpskohrvatski / српскохрватски: Pseudonauka
Tagalog: Pseudoscience
Türkçe: Sözdebilim
українська: Псевдонаука
Tiếng Việt: Giả khoa học
中文: 伪科学