The Story of the Youth Who Went Forth to Learn What Fear Was The Story of the Youth Who Went Forth to Learn What Fear Was "The Story of the Youth Who Went Forth to Learn What Fear Was" or "The Story of a Boy Who Went Forth to Learn Fear" () is a German folktale collected by the Brothers Grimm. It is tale number 4 in the collection. It was also included by Andrew Lang in "The Blue Fairy Book" (1889). The Grimms' first, 1812 edition contained a much shorter version, "Good Bowling and Card Playing" (). It is classified as its own Aarne–Thompson index type 326 of a male protagonist's unsuccessful
Proof that e is irrational between 2 and 3: We then analyze a blown-up difference "x" of the series representing "e" and its strictly smaller partial sum, which approximates the limiting value "e". By choosing the magnifying factor to be the factorial of "b", the fraction ⁄ and the partial sum are turned into integers, hence "x" must be a positive integer. However, the fast convergence of the series representation implies that the magnified approximation error "x" is still strictly smaller than 1. From this contradiction we deduce that "e" is irrational. Suppose that "e" is a rational number. Then there exist positive integers "a"