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Magic: The Gathering is Turing Complete

arxiv.org

31–40 of 194 posts

Re: Magic: The Gathering is Turing Complete

#31
post #7
post #3

erm "Though similar to role-playing fantasy games such as Dungeons and Dragons" No MTG is not at all similar to role playing games.

It is similar in lore/setting.

That was an accurate statement in, say, 1994 but boy did it diverge. Though now they've published a D&D book based on an MTG specific setting so I suppose they could converge again.

Re: Magic: The Gathering is Turing Complete

#32
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.

Some game have more states than there are atoms in the universe. They are solvable in theory but we will need a bigger universe to put this theory in practice...

Re: Magic: The Gathering is Turing Complete

#33
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.

MTG doesn’t have finite number of pieces, or finite number of actions each turn though.

Naturally people have implemented Turing machines in mtg. www.toothycat.net/~hologram/Turing

Also, the endgame criteria of mgt can be changed, but that said there is only a finite number of simple possible endgames in a sense.

Re: Magic: The Gathering is Turing Complete

#34
post #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?

No it isn't: The goal is to use a specific construction with specific cards to build a universal Turing machine.

Unlike previous attempts, which used cards that leave some room for Player agenda, this new version doesn't.

Re: Magic: The Gathering is Turing Complete

#35

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.

Loops don't really add complexity. MtG can add now tokens of arbitrary number. So that can add arbitrary complexity.

Re: Magic: The Gathering is Turing Complete

#36
post #32
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.

Some game have more states than there are atoms in the universe. They are solvable in theory but we will need a bigger universe to put this theory in practice...

Actually they are not even solvable in theory even with a bigger universe of insanely powerful computer. Which is what it means to say that mtg is Turing complete.

Re: Magic: The Gathering is Turing Complete

#37
post #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.

There is indeed no limitation on the number of tokens in a game.

There are many combo wins that involve having (technically) infinite tokens, dealing infinite damage, gaining infinite life, taking infinite turns. You get the idea.

I said technically because in practice, setting this to a very large number is enough for the win. Dealing 1e6 damage is, although possible, already way overkill in most cases when your opponent starts with 20 life.

Re: Magic: The Gathering is Turing Complete

#38
post #22

I guess this is newsworthy because a paper was put on arXiv, but the result has been known for a while. See e.g. this submission a year ago: https://news.ycombinator.com/item?id=15712377

I'll just make my submission here then as I don't want to clutter the front page [1]. The submission includes a list of a lot of things that are accidentally turing complete including Magic The Gathering.

[1] http://beza1e1.tuxen.de/articles/accidentally_turing_complet...

Re: Magic: The Gathering is Turing Complete

#39
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.

Magic The Gathering is different from the games you mentioned in that it is defined by cards that rewrite the rules of the game. There are already at least five known ways to implement Turing machines, for example:

https://www.toothycat.net/~hologram/Turing/

If you then think about the sheer number of existing M:tG cards and the implied number of possible combinations of those cards and changes to the rules (even if "optimized" to combinations that eliminate obviously nonsensical strategies like only having spells that require green mana and no sources of green mana) and the ways those cards can interact, then the computational complexity of the game explodes in ways that no other game can compare to.

And that's not even what these people showed, I think. They showed that beyond this, the complexity is worse than NP-hard.

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