Forming a hierarchy of leadership and follower is also fairly common among children. Probably fairly common among people, period. In that, you quickly start to form boundaries on who can interrupt what and why. And, in all cases, you almost always need someone that cannot be interrupted.

The article does cover this. They have moderators that would keep things on track. Most of your interactions on a daily basis don't have moderators.

This is an interesting additional aspect to the situation. I wouldn't deny at all that what you're describing happens, but whether it's a problem or a solution is debatable imo ;) Is it always better to have an enforced equality of priority among speakers, or do these emergent hierarchies serve as effective regulators of group communication?

However, I'd also argue that in most cases these social group hierarchical roles aren't going to end up having a large influence on communication style: typically it's only if there's something pressing going on. (Or, as I've already described elsewhere, if someone is unfairly taking advantage, the negation of which is a condition for cooperative interrupting to work.)

> I don't know about instant/turn play semantics so can't follow the tradeoffs there.

Magic: The Gathering works like a computer (quite literally it's Turing complete). When you play a card or ability, it is put on a stack. After you're done, you need to yield - then the other player may play things on the stack too (but, they can only play "instants" - most other cards can only be played if the stack is empty). Then they must yield, and so on.

(In the 90s, instants meant to interrupt other spells were called "interrupts", but this name was dropped)

After everyone is done, things are popped from the stack in the reverse order they were played (like any stack). So if your opponent played something in response to what you played, their card resolves first, then yours. But if you played something in response to their response, your card resolves first, then theirs, then yours.

This would be very tedious, but in fact most decks have few instants and little interaction with the stack, so most of time you play a card I will just wait it to resolve and generally wait my turn to play. And famously, no card of MtG is allowed to mention the stack in their printed text: while the concept itself is intuitive, talking about the stack is a sure way to make a card overly complicated.

We're getting a little off-topic here, but this is actually the first I'm learning that MtG can't explicitly mention the stack (I follow set releases and read cards casually sometimes, cube once in a blue moon, played standard one summer ever). That's a bit of a shame - one of the other card games I've played (Yu-Gi-Oh) works its equivalent (a "Chain") into card effects and it doesn't have to be complicated. One very good card ("Chain Strike") does damage multiplied by its stack position (chain link) so the later in the stack (chain) it appears, the more damage it does. That's not too crazy. Would've loved that either to attempt the inevitable degenerate combos or just splash it into RDW. There is also a balancing mechanism where certain effects can only be activated once per stack (chain) which is not as draconian as "per turn" but could otherwise when omitted potentially make cards ingredients in degenerate combos (e.g. "Accumulated Fortune").

Final aside: I used the phrase twice, so it should be clear that the history of said game (again, Yu-Gi-Oh) is plagued with degenerate combos.

EDIT: Editing in this edit to acknowledge that there is a sibling comment with a valid nit that invalidates the reason I responded. In my defense, my slow phone-based composition took me so long I did not see it until this edit. I'm leaving it for the sake of hopefully any nascent game designer getting any insight, I suppose. Or hey, card game players getting their kicks thinking about card game mechanics.

> no card of MtG is allowed to mention the stack in their printed text

Nit: The Split Second keyword ability is usually accompanied by reminder text which mentions the stack

> Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)

https://gatherer.wizards.com/Pages/Card/Details.aspx?multive...

Is this a recent standards change? I remember some legendary artifact that caused spells on the stack to be copied and explicitly described it that way.

Doing a search, I count 40 results with "stack" in their text; it appears that 18 of them have "split second", a few of them have "stack" in their name, several are from "Un" expansions or this weird "Mystery Booster" thing, several mention the stack in explanatory text about what it means to end the turn or end the combat phase... but there are several cards such as Grip of Chaos ("Whenever a spell or ability is put onto the stack, if it has a single target, reselect its target at random") that are from regular expansions.

https://gatherer.wizards.com/Pages/Search/Default.aspx?actio...

Welp, that's true, my bad! It seems this rule was relaxed somewhat - mentioning the stack in the rules text is still frowned upon, but there's still some cards that mention it in the rules text (and a lot more that contains the split second reminder)

Note how the waterhouse's link - https://gatherer.wizards.com/Pages/Search/Default.aspx?actio... - contains a bunch of cards that were playtested but eventually rejected (they are the black-and-white cards with just a rough sketch in place of art), presumably because of the high bar that stack-fiddling cards should meet

Tangentially, this is why I've often found it a bit easier to teach MTG to friends who also are programmers than in general; being able to tell a fellow programmer "instants are put on a stack when cast, and then are popped off the stack when they resolve" ("instant" is the term that MTG ended up standardizing on now that "interrupts" are no longer a card type) is a quick shortcut that they always end up understanding. When teaching someone who doesn't already have a mental concept of a stack data structure, I can explain how the analogy of a "stack" works, but it often takes a bit of playing and seeing it in action for them to fully internalize how it works.

Funny, as with the cards, this should be a bit easier to literally act out. Intent to play a card is to lay it down. If someone has an instant, they can put theirs on top.

That only works with cards you play from the hand, but effects that you activate on a permanent (e.g. by tapping it) also go on the stack.

Great explanation, thanks. I actually played MtG a bit when I was a kid and have a vague recollection of interrupts but don't think I understood the stack dynamics too clearly. Insightful design decision to disallow stack referencing lol.

You just blew my mind a little bit, realizing MTG gameplay was based on CS concepts, and made me fee old since interrupts is what we called them (way before I knew about processor interrupts).

To be fair, this is more that a formal system described precisely can be mapped to many computer science structures.

And I'm fairly confident these semantics exist in many cars games. Unstable Unicorns had the neigh card. Uno has the rule of declaring uno. (Where you can interrupt the next play by calling uno to force the last player to draw a card. Note that this is a very specific time you can interrupt play.)

> Magic: The Gathering works like a computer (quite literally it's Turing complete). When you play a card or ability, it is put on a stack. After you're done, you need to yield - then the other player may play things on the stack too (but, they can only play "instants" - most other cards can only be played if the stack is empty). Then they must yield, and so on.

This is actually my single least favorite part of magic compared to yugioh, and I've played both a ton. Instead of a stack, yugioh has a similar first-in-first-out concept called the chain, with two major differences:

1) Every time you place a card on the stack, you yield to your opponent, who can either play a response or yield back to you, and this goes on forever until both of you have yielded without taking an action

2) cards have "spell speeds" of 1, 2, or 3 , where you can only chain an equivalent or higher speed card - this means unlike magic, you can pile up multiple sorceries/spell speed 1 cards into the same resolution queue

Both of these encourage a ton of interaction on the stack/chain, and often times yugioh games are won or lost as the result of a resolution or 5 or more cards and effects piling up and resolving, which is a relative rarity in magic outside of a few combo decks or infinites. Conversely, yugioh also presents a lot of powerful defensive options for interrupting degenerate combos, usually at a high cost.