Fear of fish footballer Paolo Di Canio describes finding that his then team-mate, Peter Grant suffered from ichthyophobia. During a practical joke, Di Canio describes Grant's fearful reaction after finding a salmon head in his bed. Grant told "The Independent" that item in his bed was in fact a "shark's head" and "to say I got a fright when I put my feet between the sheets is an understatement." The term "ichthyophobia" comes from the Greek ἰχθῦς - "ichthus", meaning "fish" and φόβος - "phobos", "fear". "Galeophobia" comes from the Greek γαλεός - "galeos", "small shark". Fear of fish Fear of fish or
Quadratic irrational number be proved irrational. Theodorus of Cyrene proved the irrationality of the square roots of whole numbers up to 17 (except those few that are square numbers, such as 16), but stopped there, probably because the algebra he used could not be applied to the square root of numbers greater than 17. Euclid's Elements Book 10 is dedicated to classification of irrational magnitudes. The original proof of the irrationality of the non-square natural numbers depends on Euclid's lemma. Many proofs of the irrationality of the square roots of non-square natural numbers implicitly assume the fundamental theorem of arithmetic, which was first