Problem Solving

When we solve puzzles, we adopt what psychologists refer to as a 'heuristic' approach to problem solving. In other words, we search for possible entry points to the puzzle and, in so doing, we break the puzzle down into smaller, more manageable parts. As we do this, we draw on and adapt our previous knowledge about the puzzle type. Computers, on the other hand, use algorithms. In other words, they search all possible solutions until the correct one is found; it sounds rather boring to me, but that's computers for you.

Kakuro is an ideal example of the heuristic solving process in action. To begin, the solver scans the puzzle, noting the different entry points; for example, where two-cell 16 and 17 sums, or two-cell 3 and 4 sums, cross. Closer analysis unearths miniature conundrums that, one by one, are resolved. In such examples, new ideas and previous knowledge combine to determine speed of solving.

The word 'heuristic' is formed irregularly from the Greek heuriskein, meaning 'find'. It's this ability to discover or learn something for ourselves that makes puzzles so appealing.