Tin foil hat replaced with aluminium. An early allusion to an "insulative electrical contrivance encircling the head during thought" appears in the unusual 1909 non-fiction 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". The usage of a metal foil hat for protection against interference of the mind was mentioned in a science fiction short story by Julian Huxley, "The Tissue-Culture King", first published in 1926, in which the protagonist discovers that "caps of metal foil" can block the effects of
FOIL method FOIL method In elementary algebra, FOIL is a mnemonic for the standard method of multiplying two binomials—hence the method may be referred to as the FOIL method. The word "FOIL" is an acronym for the four terms of the product: The general form is: Note that is both a "first" term and an "outer" term; is both a "last" and "inner" term, and so forth. The order of the four terms in the sum is not important, and need not match the order of the letters in the word FOIL. The FOIL method is a special case of a more