Pareidolia describes a psychological phenomenon involving an ambiguous image, sound or other stimulus being falsely perceived as significant. Common examples include images of animals or faces in clouds, the man in the moon, and hidden messages on records played in reverse. The word comes from the Greek para- — amiss, faulty, wrong — and eidolon — image (the diminutive of eidos — appearance, form). The terms was first used in 1994 by Steven Goldstein.
Pareidolia is a form of apophenia, which is the false perception of patterns in unrelated meaningless data.
The Rorschach inkblot test uses pareidolia to attempt to gain insight into a person's mental state. While this test is still widely employed, its scientific basis is disputed, and no studies have shown empirical confirmation of success.
There have been many instances of perceptions of religious imagery and themes, especially the faces of religious figures, in ordinary phenomena. Many involve images of Jesus, the Virgin Mary, or the word Allah.
An early instance of possible religious pareidolia occurred in 1973, when two Pennsylvania sisters took a plane trip to Florida. While in flight, a storm arose, creating turbulence. The two sisters prayed for divine intervention. When the plane approached a Florida runway to land, Pennline looked out the window and saw a very dark cloud with a bright ray of light coming out from the right. Thompson took a photograph of the cloud, and when the roll of film was developed, saw an image that was described by their nephew Jules Massey as "God's son standing in the ray of light; an image of Him from the neck down. His face cannot be made out."
In 1978, when a New Mexican woman found that the burn marks on a tortilla she had made appeared similar to Jesus Christ's face, thousands of people came to see the framed tortilla.
The recent publicity surrounding sightings of religious figures and other surprising images in ordinary objects, combined with the growing popularity of online auctions, has spawned a market for such items on eBay. One famous instance was a grilled-cheese sandwich with the Virgin Mary's face.
In 1971, Konstantin Raudive wrote Breakthrough, detailing what he believed was the discovery of electronic voice phenomenon (EVP). EVP has been described as auditory pareidolia.
The allegations of backmasking (recording messages to be revealed when played backwards) in popular music have also been described as pareidolia.
According to Carl Sagan, human beings are, as a survival technique, "hard-wired" from birth to identify the human face. This allows people to use only minimal details to recognize faces from a distance and in poor visibility, but can also lead them to interpret random images or patterns of light and shade as being faces. Sightings of religious or iconic figures in everyday objects, such as Marian apparitions, are examples of pareidolia, as are some cases of electronic voice phenomena. The Face on Mars is a phenomenon that succeeded the Martian canals, both eventually attributed to pareidolia, when the "seen" images disappeared in better and more numerous images. Many Canadians saw the face of the Devil in the Queen's hair on Withdrawn Canadian banknotes, adapted from a photograph. The bills were not withdrawn from circulation, but the image was altered in its next printing.
C. S. Lewis
Although writing before the term "pareidolia" was coined, the theologian C. S. Lewis wrote about the implications of perception of religious imagery in questionable circumstances on issues of religious belief and faith. He argued that people's ready ability to perceive human-like forms around them reflects a religious reality that human existence is immersed in a world containing such beings. The principal reason he believed in religion was because he believed himself as wired to believe it, just as he believed human beings are wired to perceive inference (if..then) and other mental logical phenomena as representing truths about the external world that can be learned from rather than representing purely internal phenomena to be characterized as error. He chose to believe in his wiring for religious perception in the same way and for the same reasons that he chose to believe in his wiring for logic, choosing to use and rely on both as guides to learning about the world rather than regarding them as purely random in origin and discarding them. People continue to have faith in the phenomenon of logic despite the fact that they sometimes make demonstrably mistaken inferences.
Clarence Irving Lewis
In his 1929 book Mind and the World Order, epistemologist and logician Clarence Irving Lewis, a founder of the philosophical school of conceptual pragmatism, used the question of how to determine whether or not a perception is a mirage as a touchstone for his philosophical approach to knowledge. He posited two travelers in the desert who perceive an oasis in the distance. One traveler, an artist seeking a scene to paint, proceeds to paint the scene and produces a successful work. The other, seeking water to drink, pursues the image but fails to find water. Professor Lewis argued that one has no way of knowing whether or not ones perceptions are "true" in any absolute sense; all one can do is determine whether or not ones purpose is thwarted by regarding it as true and acting on that basis. According to this approach, two people with two different purposes will often have different views on whether or not to regard a perception as true. The artist, whose purpose was accomplished, could legitimately regard what he saw as real, while the thirsty traveler, whose purpose was thwarted, could legitimately regard it as an illusion.
- Yoism Video and photographic demonstrations of pareidolia
- Fortean Times examples of pareidolia in nature
- Examples of pareidolia
- Skepdic.com Skeptic's Dictionary definition of pareidolia
- A dragon on a Mexican river
- An Indian with an IPod near Medicine Hat, Alberta
- Lenin in my shower curtain
- Series of images from the news
- Koranic inscription on a fish
- The Stone Face: Fragments of An Earlier World
- Tomato with 'human face' creates sensation in Kyoto
- Natural phenomenon of Allah's Name, in Arabic
- A potato is found to bear a likeness to television's Sooty puppet
- The Pareidolia Museum By Karen Stollznow
-  Feb. 13, 2007 article in New York Times about cognitive science of face recognition.