hmm... maybe, Van, you could speak of how often in one's daily life an opinion or judgement is called for. Professional life, social life - so much weighing various aspects of whatever issue is at hand. In sudoku there is only one way to make the puzzle come out right. No maybes, just the right number in the right box. Sudoku is like a little oasis in one's day where one needn't opine or judge or weigh. It is a sort of meditative exercise.