"Good" is loosely defined here as "preferable according to humanity's extrapolated volition". The market should resolve to PROB at the percentile of goodness of the current quantum branch in the distribution of all quantum branches splitting from the time of market creation (weighted by Born rule measure). For example, if the quantum branch that the market is in ended up better than 90% of branches with the same history up to market creation, then the market should resolve to 90%. It should not resolve until it becomes possible to reliably determine this, probably using AI superintelligence. If it turns out the many-worlds interpretation of quantum mechanics is false, the market should resolve to what the answer would have been if it had been true, or if that turns out not to make sense, to N/A. By participating in this market, you agree not to (threaten to) make the world worse in order to manipulate it. I reserve the right to add further anti-vandalism clauses.

Edit 2023-01-27: I will not bet in this market.