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Magic: The Gathering is Turing Complete

arxiv.org

21–30 of 194 posts

Re: Magic: The Gathering is Turing Complete

#21
post #8

Does it actually make sense to say that something that is non-computable is most complex? That seems like a contradiction.

I think you are misunderstanding the article. The point is that when the game is considered as a computation, the problem of figuring out who is going to win is not computable. Like every discussion of the halting problem, this is about whether or not a program exists that can calculate how some other specific program will behave.

Re: Magic: The Gathering is Turing Complete

#23
From the paper:

"In this work, we solve this problem by reformulating the construction to exclusively use cards with mandatory effects."

So it's more a of a subset of MTG's rules. Still, there are commercial video games out beyond MTG and they've been out for some time. Why has the game theory field not kept up with them?

Re: Magic: The Gathering is Turing Complete

#24

It should be retitled as 'MTG is the most complex game we've played'. I would counter that other card driven games like Android Netrunner, Terraforming Mars, Lisboa, Hanabi, etc are just as or even more complex.

I have to disagree on that. At least Terraforming Mars and Hanabi have a playtime limited by ever-dwindling resources. I don't know the other games, but I suspect they also have some kind of supply that has a limit in how much it can be used/aquired.

MTG has ways to return to a previously seen play state, technically allowing a game to continue infinitely, depending on your deck, of course.

Re: Magic: The Gathering is Turing Complete

#25

Eh, just because you have a big 20000 choose 60 initial set doesn't make it "most complex".

That's not their argument either. The gist of their argument is that you can combine those cards and the legal moves they allow to encode a Turing machine and thus determining the winner is equivalent to solving the halting problem.

Re: Magic: The Gathering is Turing Complete

#26
post #16

MtG is played by choosing 60 cards from 20k. Everything is finite. There must be some generalization in order to make it noncomputable. There are probably many games that can somehow encode a halting problem if the board size is made arbitrarily large. EDIT: This from the real abstract sounds very strange: "Our result is also highly unusual in that all moves of both players are forced in the construction. This shows…

> EDIT: This from the real abstract sounds very strange:

> "Our result is also highly unusual in that all moves of both players are forced in the construction. This shows that even recognising who will win a game in which neither player has a non-trivial decision to make for the rest of the game is undecidable."

It's not so strange: the game is Turing complete, so the winner can be undecidable because who wins is the result of some arbitrarily complex computation.

Imagine we play a "game" where I win if there's a nontrivial zero of the Riemann zeta function with real part not equal to one half, otherwise you win. Neither of us has any decisions to make in this game. It's still very difficult to determine who's going to win.

Re: Magic: The Gathering is Turing Complete

#27
I'd claim strongly, that any game with:

- finite number of pieces (eg. cards)

- finite number of actions each round

- clear endgame criteria

is computionally solvable. What comes with randomness is stochasticity, but if that made game unsolvable what about poker (solved for limit heads-up) and even scrabble?

Probably it's kind of semantic problem. I'm not complexity nor game theory expert.

Re: Magic: The Gathering is Turing Complete

#29
post #27

I'd claim strongly, that any game with: - finite number of pieces (eg. cards) - finite number of actions each round - clear endgame criteria is computionally solvable. What comes with randomness is stochasticity, but if that made game unsolvable what about poker (solved for limit heads-up) and even scrabble? Probably it's kind of semantic problem. I'm not complexity nor game theory expert.

Well some cards can create additional (potentially infinite) game pieces or resources with which to preform more actions per round.

Re: Magic: The Gathering is Turing Complete

#30
post #27

I'd claim strongly, that any game with: - finite number of pieces (eg. cards) - finite number of actions each round - clear endgame criteria is computionally solvable. What comes with randomness is stochasticity, but if that made game unsolvable what about poker (solved for limit heads-up) and even scrabble? Probably it's kind of semantic problem. I'm not complexity nor game theory expert.

Actions in Magic: the Gathering let you create "tokens" which are like cards but aren't limited in number. Although you can only have a finite number in any given game, there's no upper bound on how many you can have.
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