The cut of jigsaw puzzles determines how they can be put together, but what determines how they should be is the picture painted across them.
So an ideal jigsaw puzzle has no two pieces with the same cut, preventing you from putting any pieces together incorrectly. This is largely impossible. A jigsaw puzzle where every piece has the same cut, however? That’s simply torture.
Ok, thanks - so the "cut exactly the same way" is the key here. It's maybe not so obvious to non-puzzle aficionados? I thought it simply meant "all fit together", the "same way" referring to the overall cut.
Maybe clearer: "each puzzle piece the exact same shape"?
Though it still suffers from the issue, as with a puzzle there's always the congruity of the final image as a hard guide as to what's meant to be correct, regardless of piece shape. That's maybe what muddles the analogy most.
So an ideal jigsaw puzzle has no two pieces with the same cut, preventing you from putting any pieces together incorrectly. This is largely impossible. A jigsaw puzzle where every piece has the same cut, however? That’s simply torture.