Do you enjoy doing puzzles? How about number puzzles? A recently invented number puzzle, based on logical deduction, has taken the world by storm, and that is Sudoku. In case you are one of the last hold-outs on earth not in the know about what a Sudoku puzzle is, just imagine a square composed of nine boxes, and within each of those nine boxes were nine smaller boxes, or cells. So what you have is a nine-cell by nine-cell square, in which you must place the digits 1 through 9, never repeating a digit with a line across, a column down, or one of the nine larger squares. They range in difficulty from strikingly simple to devastatingly difficult, requiring deductive reasoning to solve, rather than any kind of math skills. No adding or subtracting required.
The earliest number puzzles made their appearance in newspapers towards the end of the 19th century. One such puzzle was constructed from taking magic squares and removing some of the numbers from them. Solvers were required to discover the correct numbers which had been removed. This is different than Sudoku because it required adding to find the solution and frequently double digit numbers were involved. On November 19, 1892 a Paris newspaper published a partly finished 9×9 magic square containing 3×3 sub-squares. Although it was not a true Sudoku, it still had the same key characteristic that each row and column added up to the same number.
Three years later a competing newspaper in Paris refined this puzzle’s design until it became indistinguishable from today’s modern Sudoku. Only the number 1-9 were used, and each sub-square had the same constraints of containing each digit only once. This puzzle continued to appear in this newspaper for about ten years, until its disappearance around the beginning of the outbreak of World War One.