Just try a simple experiment. Sit in a comfortable chair, away from all distractions. Shut off your television, silence your phone, close the door and even the windows if you like. Think of any one subject. Can you do so for five minutes, without your mind straying once? For two minutes?
All your years in school, college and university have been in vain and all your years learning to swim, cycle, master this art or that science, have gone to waste if you can’t even discipline your own mind for two minutes. You can’t control what the Buddhists call your ‘monkey mind.’ It just keeps jumping from point to point, irresistibly and irresponsibly, and it seem you can do little about it. Your most important asset, your mind, you can’t restrain. Like a frisky animal, it is an undisciplined, purposeless force. When you think you have worked on a task or an idea for an hour, at least a half, possibly two-thirds, of that time your mind has been moonlighting on other distracting ideas.

What made the difference, I asked myself. The answer was obvious. My mind was in a better place, calm and collected. My skill or will was no greater than before, but my mind was better able to guide my proficiency to a higher score.

The game involves the application of two brutally basic principles, those of inclusion and exclusion. You include a number in a given cell if the other numbers in the row, column or segment require its inclusion because it is not there. On the other hand, you exclude a number from a given cell, if the other numbers do not allow it, for the simple reason that the number is already used. Yet in applying these two simple principles, you occasionally find yourself sweating, cerebrally and metaphorically of course, and cursing yourself for engaging in a masochistic time-killer.
Since I seldom have time to engage in the diversion during the day, I find myself Sudoku-embattled usually close to the midnight hour. The result is that, given a difficult puzzle, I often have to leave it half-solved – half-puzzled over what the next step ought to be. The miracle is that, when I resume after a gap of several hours, often a day, more often than not I immediately spy an opening. I find the opening so quickly and easily that I cannot help ask the question: Why do I see a breach now that I didn’t see earlier? What changed and for what reason?
Even if it is only to return to the dubious, masochistic joy of the next Sudoku.