grenv: Then I think that your analogy is both too strong and too weak. It's too strong because Chess without the king is not Chess whereas any gammon game without the cube is still the same gammon game. The scoring changes, as well as a touch of tactics, but not the game itself.

On the other hand, the cube/king analogy is too weak. If you said. referring to the game of Grasshopper itself, "Shall we play Chess where all the pieces are the same, get placed on the board one after the starting with an empty board, and where the pieces must start in the centre and each piece must touch another, and whereby placing any piece which forms lines of opponent pieces which are "bracketed" by that piece and another of the player's get turned into pieces for that player?" then you'd be about right in matching Grasshopper to Backgammon.

Or putting it a different way, if the board was unrolled so that it was flat and went in only one direction and the quadrant boundaries were drawn as hedges and the peices were turned into frogs then Grasshopper could be called Froghopper and nobody would think that it was derived from Backgammon any more than Reversi is derived from Chess.