Additionally, the legend also states that Einstein estimated that 98% of the world's population would never be able to solve his puzzle, which adds yet another layer of intimidation to this menacing, headache-inducing problem. When you add in the fact that one of the most famous logic puzzles around was reportedly invented by Albert Einstein as far back as the 19th century, you may already be considering waving the white flag before you even embark on the long and winding journey. Logic puzzles are typically viewed with an initial look of dread, their many variables and heavy wording casting a doubtful shadow over the possibility of a simple solution. How to Answer Einstein's Logic Problem, 'Who Keeps Fish?'