The history of pseudoscience is the study of pseudoscientific theories over time. A pseudoscience

Pseudoscience

Pseudoscience is a claim, belief, or practice which is presented as scientific, but which does not adhere to a valid scientific method, lacks supporting evidence or plausibility, cannot be reliably tested, or otherwise lacks scientific status...

 is a set of ideas that presents itself as science, while it does not meet the criteria to properly be called such.

Distinguishing between proper science

Science

Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...

 and pseudoscience is sometimes difficult. One popular proposal for demarcation between the two is the falsification criterion

Falsifiability

Falsifiability or refutability of an assertion, hypothesis or theory is the logical possibility that it can be contradicted by an observation or the outcome of a physical experiment...

, most notably contributed to by the philosopher Karl Popper

Karl Popper

Sir Karl Raimund Popper, CH FRS FBA was an Austro-British philosopher and a professor at the London School of Economics...

. In the history of pseudoscience it can be especially hard to separate the two, because some sciences developed from pseudosciences. An example of this is the science chemistry

Chemistry

Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....

, which traces its origins to the pseudoscience alchemy

Alchemy

Alchemy is an influential philosophical tradition whose early practitioners’ claims to profound powers were known from antiquity. The defining objectives of alchemy are varied; these include the creation of the fabled philosopher's stone possessing powers including the capability of turning base...

.

The vast diversity in pseudosciences further complicates the history of pseudoscience. Some pseudosciences originated in the pre-scientific era, such as astrology

Astrology

Astrology consists of a number of belief systems which hold that there is a relationship between astronomical phenomena and events in the human world...

 and acupuncture

Acupuncture

Acupuncture is a type of alternative medicine that treats patients by insertion and manipulation of solid, generally thin needles in the body....

. Others developed as part of an ideology, such as Lysenkoism

Lysenkoism

Lysenkoism, or Lysenko-Michurinism, also denotes the biological inheritance principle which Trofim Lysenko subscribed to and which derive from theories of the heritability of acquired characteristics, a body of biological inheritance theory which departs from Mendelism and that Lysenko named...

, or as a response to perceived threats to an ideology. An example of this is creationism

Creationism

Creationism is the religious beliefthat humanity, life, the Earth, and the universe are the creation of a supernatural being, most often referring to the Abrahamic god. As science developed from the 18th century onwards, various views developed which aimed to reconcile science with the Genesis...

, which was developed as a response to the scientific theory of evolution.

Despite failing to meet proper scientific standards, many pseudosciences survive. This is usually due to a persistent core of devotees

True-believer syndrome

True-believer syndrome is an informal or rhetorical term coined by M. Lamar Keene in his 1976 book The Psychic Mafia. Keene used the term to refer to people who continued to believe in a paranormal event or phenomenon even after it had been proven to have been staged...

 who refuse to accept scientific criticism of their beliefs, or due to popular misconceptions. Sheer popularity is also a factor, as is attested by astrology which remains popular despite being rejected by a large majority of scientists.

19th century

Among the most notable developments in the history of pseudoscience in the 19th century are the rise of Spiritualism

Spiritualism (beliefs)

Spiritualism is a dualist metaphysical belief that the world is made up of at least two fundamental substances, matter and spirit. This very broad metaphysical distinction is further developed into many and various forms by the inclusion of details about what spiritual entities exist such as a...

 (traced in America to 1848), homeopathy

Homeopathy

Homeopathy is a form of alternative medicine in which practitioners claim to treat patients using highly diluted preparations that are believed to cause healthy people to exhibit symptoms that are similar to those exhibited by the patient...

 (first formulated in 1796), and phrenology

Phrenology

Phrenology is a pseudoscience primarily focused on measurements of the human skull, based on the concept that the brain is the organ of the mind, and that certain brain areas have localized, specific functions or modules...

 (developed around 1800). Another popular pseudoscientific belief that arose during the 19th century was the idea that there were canals visible on Mars. A relatively mild Christian fundamentalist backlash against the scientific theory of evolution foreshadowed subsequent events in the 20th century.

The study of bumps and fissures in people's skulls to determine their character, phrenology

Phrenology

Phrenology is a pseudoscience primarily focused on measurements of the human skull, based on the concept that the brain is the organ of the mind, and that certain brain areas have localized, specific functions or modules...

, was originally considered a science. It influenced psychiatry and early studies into neuroscience. As science advanced, phrenology was increasingly viewed as a pseudoscience. Halfway through the 19th century, the scientific community had prevailingly abandoned it.

Halfway through the century, iridology

Iridology

Iridology Iridology Iridology (also known as iridodiagnosis or iridiagnosis is an alternative medicine technique whose proponents claim that patterns, colors, and other characteristics of the iris can be examined to determine information about a patient's systemic health...

was invented by the Hungarian physician Ignaz von Peczely

Ignaz von Peczely

Ignaz von Peczely was a Hungarian physician, who is credited with the invention or re-invention of the pseudoscientific theory of iridology. Von Peczely first thought of iridology when caring for an owl with a broken leg. After noticing a spot in the owl's eye he hypothesized a link between the...

. The theory would remain popular throughout the 20th century as well.

Spiritualism

Spiritualism (beliefs)

Spiritualism is a dualist metaphysical belief that the world is made up of at least two fundamental substances, matter and spirit. This very broad metaphysical distinction is further developed into many and various forms by the inclusion of details about what spiritual entities exist such as a...

(sometimes referred to as "Modern Spiritualism" or "Spiritism") or "Modern American Spiritualism" grew phenomenally during the period. The American version of this movement has been traced to the Fox sisters

Fox sisters

The Fox sisters were three sisters from New York who played an important role in the creation of Spiritualism. The three sisters were Leah Fox , Margaret Fox and Kate Fox . The two younger sisters used "rappings" to convince their much older sister and others that they were communicating with...

 who in 1848 began claiming the ability to communicate with the dead. The religious movement would remain popular until the 1920s, when renowned magician Harry Houdini

Harry Houdini

Harry Houdini was a Hungarian-born American magician and escapologist, stunt performer, actor and film producer noted for his sensational escape acts...

 began exposing famous mediums and other performers as frauds (see also Harry Houdini#Debunking spiritualists). While the religious beliefs of Spiritualism are not presented as science, and thus are not properly considered pseudoscientific, the movement did spawn numerous pseudoscientific phenomena such as ectoplasm

Ectoplasm (paranormal)

Ectoplasm is a term coined by Charles Richet to denote a substance or spiritual energy "exteriorized" by physical mediums...

 and spirit photography

Spirit photography

Spirit photography is a type of photography whose primary attempt is to capture images of ghosts and other spiritual entities, especially in ghost hunting. It was first used by William H. Mumler in the 1860s. Mumler discovered the technique by accident, after he discovered a second person in a...

.

The principles of homeopathy

Homeopathy

Homeopathy is a form of alternative medicine in which practitioners claim to treat patients using highly diluted preparations that are believed to cause healthy people to exhibit symptoms that are similar to those exhibited by the patient...

were first formulated in 1796, by German physician Samuel Hahnemann

Samuel Hahnemann

Christian Friedrich Samuel Hahnemann was a German physician, known for creating an alternative form of medicine called homeopathy.- Early life :Christian Friedrich Samuel Hahnemann was born in Meissen, Saxony near Dresden...

. At the time, mainstream medicine was a primitive affair and still made use of techniques such as bloodletting

Bloodletting

Bloodletting is the withdrawal of often little quantities of blood from a patient to cure or prevent illness and disease. Bloodletting was based on an ancient system of medicine in which blood and other bodily fluid were considered to be "humors" the proper balance of which maintained health...

. Homeopathic medicine by contrast consisted of extremely diluted substances, which meant that patients basically received water. Compared to the damage often caused by conventional medicine, this was an improvement. During the 1830s homeopathic institutions and schools spread across the USA and Europe. Despite these early successes, homeopathy was not without its critics. Its popularity was on the decline before the end of the 19th century, though it has been revived in the 20th century.

The supposed Martian canals were first reported in 1877, by the Italian astronomer Giovanni Schiaparelli

Giovanni Schiaparelli

Giovanni Virginio Schiaparelli was an Italian astronomer and science historian. He studied at the University of Turin and Berlin Observatory. In 1859-1860 he worked in Pulkovo Observatory and then worked for over forty years at Brera Observatory...

. The belief in them peaked in the late 19th century, but was widely discredited in the beginning of the 20th century.

The publication of Atlantis: The Antediluvian World

Atlantis: The Antediluvian World

Atlantis: The Antediluvian World is a book published during 1882 by Minnesota populist politician Ignatius L. Donnelly, who was born in Philadelphia, Pennsylvania during 1831...

by politician and author Ignatius L. Donnelly in 1882, renewed interest in the ancient idea of Atlantis

Atlantis

Atlantis is a legendary island first mentioned in Plato's dialogues Timaeus and Critias, written about 360 BC....

. This highly advanced society supposedly existed several millennia before the rise of civilizations like Ancient Egypt

Ancient Egypt

Ancient Egypt was an ancient civilization of Northeastern Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh...

. It was first mentioned by Plato

Plato

Plato , was a Classical Greek philosopher, mathematician, student of Socrates, writer of philosophical dialogues, and founder of the Academy in Athens, the first institution of higher learning in the Western world. Along with his mentor, Socrates, and his student, Aristotle, Plato helped to lay the...

, as a literary device in two of his dialogues. Other stories of lost continents, such as Mu

Mu (lost continent)

Mu is the name of a hypothetical continent that allegedly existed in one of Earth's oceans, but disappeared at the dawn of human history.The concept and the name were proposed by 19th century traveler and writer Augustus Le Plongeon, who claimed that several ancient civilizations, such as those of...

 and Lemuria

Lemuria (continent)

Lemuria is the name of a hypothetical "lost land" variously located in the Indian and Pacific Oceans. The concept's 19th century origins lie in attempts to account for discontinuities in biogeography; however, the concept of Lemuria has been rendered obsolete by modern theories of plate tectonics...

 also arose during the late 19th century.

In 1881 the Dutch

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 Vereniging tegen de Kwakzalverij

Vereniging tegen de Kwakzalverij

The Vereniging tegen de Kwakzalverij is a Dutch organization that investigates the claims of alternative medicine and opposes quackery. Ever since its foundation in 1881 the organization has published a magazine, currently titled Nederlands Tijdschrift tegen de Kwakzalverij...

 (English

English language

English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...

: Society against Quackery) was formed to oppose pseudoscientific trends in medicine. It is still active.

20th century

Among the most notable developments to pseudoscience in the 20th century are the rise of Creationism

Creationism

Creationism is the religious beliefthat humanity, life, the Earth, and the universe are the creation of a supernatural being, most often referring to the Abrahamic god. As science developed from the 18th century onwards, various views developed which aimed to reconcile science with the Genesis...

, the demise of Spiritualism

Spiritualism

Spiritualism is a belief system or religion, postulating the belief that spirits of the dead residing in the spirit world have both the ability and the inclination to communicate with the living...

, and the first formulation of ancient astronaut theories

Ancient astronauts

Some writers have proposed that intelligent extraterrestrial beings have visited Earth in antiquity or prehistory and made contact with humans. Such visitors are called ancient astronauts or ancient aliens. Proponents suggest that this contact influenced the development of human cultures,...

.

Reflexology

Reflexology

Reflexology, or zone therapy, is an alternative medicine involving the physical act of applying pressure to the feet, hands, or ears with specific thumb, finger, and hand techniques without the use of oil or lotion...

, the idea that an undetectable life force connects various parts of the body to the feet and sometimes the hands and ears, was introduced in the USA in 1913 as 'zone therapy'.

Creationism

Creationism

Creationism is the religious beliefthat humanity, life, the Earth, and the universe are the creation of a supernatural being, most often referring to the Abrahamic god. As science developed from the 18th century onwards, various views developed which aimed to reconcile science with the Genesis...

arose during the 20th century as a result of various other historical developments. When the modern evolutionary synthesis

Modern evolutionary synthesis

The modern evolutionary synthesis is a union of ideas from several biological specialties which provides a widely accepted account of evolution...

 overcame the eclipse of Darwinism in the first half of the 20th century, American fundamentalist Christians

Fundamentalist Christianity

Christian fundamentalism, also known as Fundamentalist Christianity, or Fundamentalism, arose out of British and American Protestantism in the late 19th century and early 20th century among evangelical Christians...

 began opposing the teaching of the theory of evolution in public schools. They introduced numerous laws to this effect, one of which was notoriously upheld by the Scopes Trial

Scopes Trial

The Scopes Trial—formally known as The State of Tennessee v. John Thomas Scopes and informally known as the Scopes Monkey Trial—was a landmark American legal case in 1925 in which high school science teacher, John Scopes, was accused of violating Tennessee's Butler Act which made it unlawful to...

.
In the second half of the century the Space Race

Space Race

The Space Race was a mid-to-late 20th century competition between the Soviet Union and the United States for supremacy in space exploration. Between 1957 and 1975, Cold War rivalry between the two nations focused on attaining firsts in space exploration, which were seen as necessary for national...

 caused a renewed interest in science and worry that the USA was falling behind on the Soviet Union. Stricter science standards were adopted and led to the re-introduction of the theory of evolution in the curriculum. The laws against teaching evolution were now ruled unconstitutional, because they violated the separation of church and state

Separation of church and state

The concept of the separation of church and state refers to the distance in the relationship between organized religion and the nation state....

. Attempting to evade this ruling, the Christian fundamentalists produced a supposedly secular alternative to evolution, Creationism. Perhaps the most influential publication of this new pseudoscience was The Genesis Flood by young earth creationists

Young Earth creationism

Young Earth creationism is the religious belief that Heavens, Earth, and all life on Earth were created by direct acts of the Abrahamic God during a relatively short period, sometime between 5,700 and 10,000 years ago...

 John C. Whitcomb

John C. Whitcomb

John Clement Whitcomb, Jr. is an American Old Testament theologian and young earth creationist. Whitcomb is sometimes credited for establishing the modern young earth creationist/creation science movement by authoring with Henry M...

 and Henry M. Morris

Henry M. Morris

Henry Madison Morris was an American young earth creationist and Christian apologist. He was one of the founders of the Creation Research Society and the Institute for Creation Research...

.

The dawn of the space age also inspired various versions of ancient astronaut theories

Ancient astronauts

Some writers have proposed that intelligent extraterrestrial beings have visited Earth in antiquity or prehistory and made contact with humans. Such visitors are called ancient astronauts or ancient aliens. Proponents suggest that this contact influenced the development of human cultures,...

. While differences between the specific theories exists, they share the idea that intelligent extraterrestrials visited Earth in the distant past and made contact with then living humans. Popular authors, such as Erich von Däniken

Erich von Däniken

Erich Anton Paul von Däniken is a Swiss author best known for his controversial claims about extraterrestrial influences on early human culture, in books such as Chariots of the Gods?, published in 1968...

 and Zecharia Sitchin

Zecharia Sitchin

Zecharia Sitchin was an Azerbaijani-born American author of books promoting an explanation for human origins involving ancient astronauts. Sitchin attributes the creation of the ancient Sumerian culture to the Anunnaki, which he states was a race of extra-terrestrials from a planet beyond Neptune...

, began publishing in the 1960s. Among the most notable publications in the genre is Chariots of the Gods?, which appeared in 1968.

The Apollo

Project Apollo

The Apollo program was the spaceflight effort carried out by the United States' National Aeronautics and Space Administration , that landed the first humans on Earth's Moon. Conceived during the Presidency of Dwight D. Eisenhower, Apollo began in earnest after President John F...

 Moon landing

Moon landing

A moon landing is the arrival of a spacecraft on the surface of the Moon. This includes both manned and unmanned missions. The first human-made object to reach the surface of the Moon was the Soviet Union's Luna 2 mission on 13 September 1959. The United States's Apollo 11 was the first manned...

s from the 1960s through the 70's gave rise to a number of Apollo Moon Landing hoax conspiracy theories. These conspiracy theories

Conspiracy theory

A conspiracy theory explains an event as being the result of an alleged plot by a covert group or organization or, more broadly, the idea that important political, social or economic events are the products of secret plots that are largely unknown to the general public.-Usage:The term "conspiracy...

 are universally ignored by the scientific community, but at the end of the century a Gallup

The Gallup Organization

The Gallup Organization, is primarily a research-based performance-management consulting company. Some of Gallup's key practice areas are - Employee Engagement, Customer Engagement and Well-Being. Gallup has over 40 offices in 27 countries. World headquarters are in Washington, D.C. Operational...

 poll showed 6 percent of the American population did not believe the landings were genuine.

Late in the 20th century several prominent skeptical

Scientific skepticism

Scientific skepticism is the practice of questioning the veracity of claims lacking empirical evidence or reproducibility, as part of a methodological norm pursuing "the extension of certified knowledge". For example, Robert K...

 foundations were formed to counter the growth of pseudosciences. In the USA, the most notable of these are, in chronological order, the Center for Inquiry

Center for Inquiry

The Center for Inquiry is a non-profit educational organization with headquarters in the United States whose primary mission is to encourage evidence-based inquiry into paranormal and fringe science claims, alternative medicine and mental health practices, religion, secular ethics, and society...

 (1991), The Skeptics Society

The Skeptics Society

The Skeptics Society is a nonprofit, member-supported organization devoted to promoting scientific skepticism and resisting the spread of pseudoscience, superstition, and irrational beliefs. The Skeptics Society was originally founded as a Los Angeles-area skeptical group to replace the defunct...

 (1992), the James Randi Educational Foundation

James Randi Educational Foundation

The James Randi Educational Foundation is a non-profit organization founded in 1996 by magician and skeptic James Randi. The JREF's mission includes educating the public and the media on the dangers of accepting unproven claims, and to support research into paranormal claims in controlled...

 (1996), and the New England Skeptical Society

New England Skeptical Society

The New England Skeptical Society is a non-profit educational organization dedicated to promoting science and reason. It was originally founded in January 1996 as the Connecticut Skeptical Society...

 (1996). The Committee for Skeptical Inquiry, which has similar goals, had already been founded in 1976. It became part of the Center for Inquiry as part of the foundation of the latter in 1991. In the Netherlands Stichting Skepsis

Stichting Skepsis

Stichting Skepsis is a Dutch organization dedicated to the promotion and practice of scientific skepticism. Since 1988 the organization publishes a journal titled Skepter twice a year...

 was founded in 1987.

21st century

At the beginning of the 21st century, a variety of pseudoscientific theories remain popular.

Creationism, in the form of Intelligent Design

Intelligent design

Intelligent design is the proposition that "certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection." It is a form of creationism and a contemporary adaptation of the traditional teleological argument for...

, suffered a major legal defeat in the Kitzmiller v. Dover Area School District

Kitzmiller v. Dover Area School District

Tammy Kitzmiller, et al. v. Dover Area School District, et al. was the first direct challenge brought in the United States federal courts testing a public school district policy that required the teaching of intelligent design...

 trial. Judge John E. Jones III

John E. Jones III

John Edward Jones III is an American lawyer and jurist from the U.S. state of Pennsylvania. A Republican, Jones was appointed by President George W. Bush as federal judge on the United States District Court for the Middle District of Pennsylvania in February 2002 and was unanimously confirmed by...

 ruled that Intelligent Design is inseparable from Creationism, and its teaching in public schools violates the Establishment Clause of the First Amendment

Establishment Clause of the First Amendment

The Establishment Clause is the first of several pronouncements in the First Amendment to the United States Constitution, stating, Together with the Free Exercise Clause The Establishment Clause is the first of several pronouncements in the First Amendment to the United States Constitution,...

. The trial sparked much interest, and was the subject of several documentaries including the award winning NOVA

NOVA (TV series)

Nova is a popular science television series from the U.S. produced by WGBH Boston. It can be seen on the Public Broadcasting Service in the United States, and in more than 100 other countries...

 production Judgment Day: Intelligent Design on Trial

Judgment Day: Intelligent Design on Trial

Judgment Day: Intelligent Design on Trial is an award-winning NOVA documentary on the case of Kitzmiller v. Dover Area School District, which concentrated on the question of whether or not intelligent design could be viewed as science and taught in school science class...

(2007).

The pseudoscientific idea that vaccines cause autism

Thiomersal controversy

The thiomersal controversy describes claims that vaccines containing the mercury-based preservative thiomersal contribute to the development of autism and other brain development disorders...

originated in the 1990s, but became prominent in the media during the first decade of the 21st century. Despite a broad scientific consensus

Scientific consensus

Scientific consensus is the collective judgment, position, and opinion of the community of scientists in a particular field of study. Consensus implies general agreement, though not necessarily unanimity. Scientific consensus is not by itself a scientific argument, and it is not part of the...

 against the idea that there is a link between vaccination

Vaccination

Vaccination is the administration of antigenic material to stimulate the immune system of an individual to develop adaptive immunity to a disease. Vaccines can prevent or ameliorate the effects of infection by many pathogens...

 and autism

Autism

Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...

, several celebrities have joined the debate. Most notable of these is Jenny McCarthy

Jenny McCarthy

Jennifer Ann "Jenny" McCarthy is an American model, comedian, actress, author, activist, and game show host. She began her career in 1993 as a nude model for Playboy magazine and was later named their Playmate of the Year. McCarthy then parlayed her Playboy fame into a successful television and...

, whose son has autism.
In February 2009, surgeon Andrew Wakefield

Andrew Wakefield

Andrew Wakefield is a British former surgeon and medical researcher, known as an advocate for the discredited claim that there is a link between the measles, mumps and rubella vaccine, autism and bowel disease, and for his fraudulent 1998 research paper in support of that claim.Four years after...

, who published the originally research supposedly indicating a link between vaccines and autism, was reported to have fixed the data by The Sunday Times

The Sunday Times

The Sunday Times is a British Sunday newspaper.The Sunday Times may also refer to:*The Sunday Times *The Sunday Times *The Sunday Times *The Sunday Times...

. A hearing by the General Medical Council

General Medical Council

The General Medical Council registers and regulates doctors practising in the United Kingdom. It has the power to revoke or restrict a doctor's registration if it deems them unfit to practise...

 had already begun in March 2007, examining charges of professional misconduct.

The most notable development in the ancient astronauts genre was the opening of Erich von Däniken's Mystery Park in 2003. While the park had a good first year, the number of visitors was much lower than the expected 500,000 a year. This caused financial difficulties, which led to the closure of the park in 2006.

Histories of specific pseudosciences

• History of astrology
  History of astrology
  Astrology, the belief in a connection between the cosmos and terrestrial matters has played an important part in human history.Regional branches of astrology include Western astrology, Indian astrology, and Chinese or East Asian astrology.-Early origins:...
  
  
• History of creationism
  History of creationism
  The history of creationism relates to the history of thought based on a premise that the natural universe had a beginning, and came into being supernaturally...
  
  
• History of perpetual motion machines
  History of perpetual motion machines
  The history of perpetual motion machines dates back to the Middle Ages. For millennia, it was not clear whether perpetual motion devices were possible or not, but the development of modern theories of thermodynamics has indicated that they are impossible. Despite this, many attempts have been made...