possible outcomes of an interaction or trade:
(+100, +100) everybody gets what they want! it’s win-win!
(+50, +50) we had to compromise but it’s fair and still good.
(+100, 0) I got mine, and you’re no worse off anyway.
(0, 0) the neutral default, a nil-all draw.
(+100, -100) exploitation, robbery, zero-sum competition.
(-100, 0) I got whacked and you didn’t even benefit from it.
(-100, -100) scorched earth, everybody dies.