In Monkey 2 there is a puzzle where you have to cut the peg leg of a pirate, so that the carpenter will be called to repair it, and while he is away you can sneak into his shop and take the nails and the hammer.
Let me spell out the reasoning that Guybrush would need to do in order to solve this puzzle:
“I need to take the hammer. But the carpenter won’t let me. Idea: maybe I can send him away somehow. But how? Idea: maybe if I break something that’s made of wood , he will be called to repair it. And then I’ll sneak in. Ok, so let us look in town for something that’s made of wood and that I can break: look, there’s a peg leg here. Maybe I can saw this one”.
Now, personally I am in awe at how good this puzzle is. As you can see, this puzzle can be solved in a purely deductive way (or more precisely “abductive”), starting from the goal and reasoning backwards. You can arrive purely through logic at the conclusion that you need to cut the peg leg.
However, I suspect that almost nobody on earth solved the puzzle like this. I believe who solved it did a completely different reasoning:
“I have this saw in my inventory. What can I do with it? Well, saws saw wood. Now, what is around that is made of wood? Look: there’s a peg leg here. Let’s try to combine them, and see what happens.”
What can we say about this second way to solve the puzzle?
-
this is not “goal-driven” reasoning: you don’t start from the goal and arrive, in a purely deductive way, to understand what you need to do to reach the goal.
-
this is “meta-reasoning”, i.e. it only works if you know you are in a videogame. SINCE I am playing a videogame AND I have a saw, THEN I probably need to use it on something. And so on. But Guybrush would never know this. Only the player knows this.
At any rate, this is still a kind of reasoning. (not brute-force) So the puzzle can be solved in two ways.
Now, personally I have a feeling that this second way to solve the puzzle is “improper”, and the first is “proper”. Probably because the second way is very similar to brute forcing. OTOH, I am sure someone will say “who are you to say what is the proper reasoning to solve a puzzle?”. So I’d like to ask everybody how they feel about this. If you were the designer of such a puzzle, would you not be worried that the player might solve the puzzle in this second way, and in practice almost everybody will? (and if so, what can you as a designer do about this?)