A tin foil hat is a

hat A hat is a head covering which is worn for various reasons, including protection against weather conditions, ceremonial reasons such as university graduation, religious reasons, safety, or as a fashion accessory. Hats which incorporate mecha ...

made from one or more sheets of

aluminium foil Aluminium foil (or aluminum foil in North American English; often informally called tin foil) is aluminium prepared in thin metal leaves with a thickness less than ; thinner gauges down to are also commonly used. Standard household foil is typ ...

(commonly called "tin foil" in the United States and New Zealand), or a piece of conventional headgear lined with foil, often worn in the belief or hope that it shields the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a ve ...

from threats such as electromagnetic fields,

mind control Brainwashing (also known as mind control, menticide, coercive persuasion, thought control, thought reform, and forced re-education) is the concept that the human mind can be altered or controlled by certain psychological techniques. Brainwashin ...

, and mind reading. The notion of wearing homemade headgear for such protection has become a popular stereotype and byword for

paranoia Paranoia is an instinct or thought process that is believed to be heavily influenced by anxiety or fear, often to the point of delusion and irrationality. Paranoid thinking typically includes persecutory beliefs, or beliefs of conspiracy co ...

persecutory delusions Persecution is the systematic mistreatment of an individual or group by another individual or group. The most common forms are religious persecution, racism, and political persecution, though there is naturally some overlap between these terms ...

, and belief in

pseudoscience Pseudoscience consists of statements, beliefs, or practices that claim to be both scientific and factual but are incompatible with the scientific method. Pseudoscience is often characterized by contradictory, exaggerated or unfalsifiable clai ...

and

conspiracy theories A conspiracy theory is an explanation for an event or situation that invokes a conspiracy by sinister and powerful groups, often political in motivation, when other explanations are more probable.Additional sources: * * * * The term has a nega ...

. "

Tin foil Tin foil, also spelled tinfoil, is a thin foil made of tin. Tin foil was superseded after World War II by cheaper and more durable aluminium foil, which is still referred to as "tin foil" in many regions (an example of a misnomer). History ...

" is a common misnomer for aluminium foil; packaging metal foil was formerly made out of

tin Tin is a chemical element with the symbol Sn (from la, stannum) and atomic number 50. Tin is a silvery-coloured metal. Tin is soft enough to be cut with little force and a bar of tin can be bent by hand with little effort. When bent, t ...

before it was replaced with

aluminium Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. I ...

Origin

Some people – "Tin Foil Hatters" – have a belief that such hats prevent mind control by governments, spies, mobsters, corporations, or paranormal beings that employ

ESP ESP most commonly refers to: * Extrasensory perception, a paranormal ability ESP may also refer to: Arts, entertainment Music * ESP Guitars, a manufacturer of electric guitars * E.S. Posthumus, an independent music group formed in 2000, ...

or the

microwave auditory effect The microwave auditory effect, also known as the microwave hearing effect or the Frey effect, consists of the human perception of audible clicks, or even speech, induced by pulsed or modulated radio frequencies. The communications are generated di ...

. People in many countries who believe they are " targeted individuals", subject to government, corporate, or criminal spying or harassment, have developed websites, conference calls, and support meetings to discuss their concerns, including the idea of protective headgear. ''Vice Magazine'' wrote that the tin foil hat in popular culture "can be traced back in a very weird and prescient short story written in 1927 by Julian Huxley" titled " The Tissue-Culture King", wherein the main character uses a metal hat to prevent being mind controlled by the villain scientist. Over time the term "tin foil hat" has become associated with

and

Scientific basis

Effects of strong electromagnetic radiation on health have been documented for quite some time. The efficiency of a metal enclosure in blocking electromagnetic radiation depends on the thickness of the foil, as dictated by the "

skin depth Skin effect is the tendency of an alternating electric current (AC) to become distributed within a conductor such that the current density is largest near the surface of the conductor and decreases exponentially with greater depths in the co ...

" of the conductor for a particular wave frequency range of the radiation. For half-millimetre-thick aluminum foil, radiation above about 20 kHz (i.e., including both AM and

FM band The FM broadcast band is a range of radio frequencies used for FM broadcasting by radio stations. The range of frequencies used differs between different parts of the world. In Europe and Africa (defined as International Telecommunication Union ( ...

s) would be partially blocked, although aluminum foil is not sold in this thickness, so numerous layers of foil would be required to achieve this effect. In 1962, Allan H. Frey discovered that the

(i.e., the reception of the induced sounds by radio-frequency electromagnetic signals heard as clicks and buzzes) can be blocked by a patch of

wire mesh Overhead power cabling. The conductor consists of seven strands of steel (centre, high tensile strength), surrounded by four outer layers of aluminium (high conductivity). Sample diameter 40 mm A wire is a flexible strand of metal. Wire is co ...

(rather than foil) placed above the

temporal lobe The temporal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The temporal lobe is located beneath the lateral fissure on both cerebral hemispheres of the mammalian brain. The temporal lobe is involved in pro ...

. In 2005, a

tongue-in-cheek The idiom tongue-in-cheek refers to a humorous or sarcastic statement expressed in a serious manner. History The phrase originally expressed contempt, but by 1842 had acquired its modern meaning. Early users of the phrase include Sir Walter Scot ...

experimental study by a group of MIT students found that tin foil hats do shield their wearers from radio waves over most of the tested spectrum, but amplified certain frequencies, around 2.6 GHz and 1.2 GHz. In 2022, anti-vaccination protesters in

Wellington Wellington ( mi, Te Whanganui-a-Tara or ) is the capital city of New Zealand. It is located at the south-western tip of the North Island, between Cook Strait and the Remutaka Range. Wellington is the second-largest city in New Zealand by metr ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

were seen wearing tinfoil hats, in a mistaken belief that their illnesses – possibly

COVID-19 Coronavirus disease 2019 (COVID-19) is a contagious disease caused by a virus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first known case was identified in Wuhan, China, in December 2019. The disease quickly ...

– were being caused by electromagnetic rays fired at them by the Government.

In popular culture

In 2005,

Bruce Perens Bruce Perens (born around 1958) is an American computer programmer and advocate in the free software movement. He created The Open Source Definition and published the first formal announcement and manifesto of open source. He co-founded the Open ...

reported on an encounter between

Richard Stallman Richard Matthew Stallman (; born March 16, 1953), also known by his initials, rms, is an American free software movement activist and programmer. He campaigns for software to be distributed in such a manner that its users have the freedom to ...

and security personnel at the UN World Summit on the Information Society, titled "Stallman Gets in Trouble with UN Security for Wearing a Tin-Foil Hat". The tin-foil hat in the title was figurative, as Stallman did not actually devise a tin-foil hat, but instead wrapped an identification card containing a radio-frequency identification device in tin foil in protest against the intrusion on his privacy. In a 2016 article, the musician and researcher Daniel Wilson writing in paranormal magazine ''

Fortean Times ''Fortean Times'' is a British monthly magazine devoted to the anomalous phenomena popularised by Charles Fort. Previously published by John Brown Publishing (from 1991 to 2001), I Feel Good Publishing (2001 to 2005), Dennis Publishing (2005 to 2 ...

'' noted an early allusion to an "insulative electrical contrivance encircling the head during thought" in the unusual 1909

non-fiction Nonfiction, or non-fiction, is any document or media content that attempts, in good faith, to provide information (and sometimes opinions) grounded only in facts and real life, rather than in imagination. Nonfiction is often associated with b ...

publication ''Atomic Consciousness'' by self-proclaimed "seer" John Palfrey (aka "James Bathurst") who believed such headgear was not effective for his "retention of thoughts and ideas" against a supposed "telepathic impactive impingement". Tin foil hats have appeared in such films as '' Signs'' (2002), '' Noroi: The Curse'' (2005), and '' Futurama: Into the Wild Green Yonder'' (2009). The 2019 HBO television series ''

Watchmen ''Watchmen'' is an American comic book maxiseries by the British creative team of writer Alan Moore, artist Dave Gibbons and colorist John Higgins. It was published monthly by DC Comics in 1986 and 1987 before being collected in a single-vo ...

'' features the character Wade Tillman/Looking Glass, a police officer who wears a mask made of reflective foil, and while off-duty, a cap lined in foil to protect his mind from alien psychic attacks.

References

External links

* {{DEFAULTSORT:Tin Foil Hat Hats Mind control Paranoia Pseudoscience Pejorative terms for people Protective gear

Origin

Scientific basis

In popular culture

See also

References

External links