What Is an Experience Point Worth?

It seems like a simple question, but the way you answer it may, in effect, determine the metaphysics of your game. Many RPGs use some sort of "experience point" system to model growth and learning. The progenitor of this idea is, of course, Dungeons & Dragons; the Experience Point (XP) system has been a core feature of the game from the beginning.

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Yet what exactly an experience point is remains unclear.

Think about it: can anyone earn an XP under the right circumstances? Or must one possess a class? If so, what qualifies an individual for a class? The 1st-edition Dungeon Master’s Guide specifies that henchmen earn 50 percent of the group’s XP award. In other words, they get a full share awarded, but then only "collect" half the share. Where does the other half go? Did it ever exist in the first place?

These esoteric questions were highlighted for me recently when I recreated a 20-year-old D&D character from memory for a new campaign I’m playing in. All I could remember of this character from my high school days was her race and class (half-elf Bladesinger, because I liked the cheese, apparently) and that the campaign fizzled out after only a handful of sessions. If I made it to level 2 back then, I couldn’t rightly say.

I asked my Dungeon Master (DM)—the same fellow who had run the original game for me back in the days of the Clinton administration—whether I could start a level ahead, or at least with a randomly-determined amount of XP (say, 200+2D100). Being the stern taskmaster that he is, he shot down both suggestions, saying instead that I’d be starting at 0 XP and at level 1, just like the rest of the party. As justification, he said that my character had amassed 0 XP for this campaign.

As the character probably only had a few hundred XP to her name to begin with, I let the matter slide. But it did get me thinking: do Experience Points only exist within the context of individual campaigns? Was my DM onto something?

This sort of thinking can in turn lead down quite a rabbit hole. Are classes themselves an arbitrary construct? Do they exist solely for players, or are non-player characters (NPCs) also capable of possessing classes and levels? Different editions of D&D have presented different interpretations of this question, from essentially statting up all NPCs as monsters, with their own boutique abilities (as in the earliest iterations of the game), to granting NPCs levels in "non-adventuring classes" (the famous 20th-level Commoner of 3rd-edition days).

The current edition of D&D has come back around to limiting classes and XP awards to player-characters only—which brings us back to our original question: are Experience Points, like character classes, meant to function solely as an abstract game mechanic, or are they an objective force within the game world? How do you, the reader at home, treat XP in your campaigns?

contributed by David Larkins

 

[Manbearcat]

Few comments on the "contrived" component of conversation that @pemerton and @Saelorn:

1) D&D and all TTRPGs have a premise (sometimes multiple), themes, and tropes.

2) D&D and all TTRPGs have machinery/procedures by which (a) the game is expected to be facilitated and (b) the fiction is meant to be generated and interfaced with by physical players who are not able to actually interact with/inhabit the imaginary space which the participants are to share.

Given 1 and 2 above, I'm left wondering how is that D&D specifically, and TTRPGs generally, are going to be anything but overburdened by contrivance?

1 contracts the creative space such that it focuses it on very specific things to the exclusion of other things.

2 makes a game of imagination capable of being played at all (while still being called a game) and enables the distillation of and interaction with 1.

The only way I see to remove or significantly mitigate the "contrivance-based" nature of TTRPGing is to broaden, vanillia-ize, or dilute a game's premise (which you buy into to play at all!), themes, and tropes such that it is barely recognizable as a thing...and then have super generic rules that don't perpetuate much of anything.

I'm thinking:

"Lets play a game!"

"Ok, what kind of game?"

"A game where you do stuff!"

"What kind of stuff?"

"Stuff that happens!"

"Ummmm...ok, what is the game about?"

"Whatever!"

"Ummmm...how do we make stuff happen in this game about whatever?"

"You tell me what you want to do and I'll just tell you what happens...maybe if you give me candy better stuff will happen?"

 

[pemerton]

1) D&D and all TTRPGs have a premise (sometimes multiple), themes, and tropes.

2) D&D and all TTRPGs have machinery/procedures by which (a) the game is expected to be facilitated and (b) the fiction is meant to be generated and interfaced with by physical players who are not able to actually interact with/inhabit the imaginary space which the participants are to share.

Given 1 and 2 above, I'm left wondering how is that D&D specifically, and TTRPGs generally, are going to be anything but overburdened by contrivance?

1 contracts the creative space such that it focuses it on very specific things to the exclusion of other things.

2 makes a game of imagination capable of being played at all (while still being called a game) and enables the distillation of and interaction with 1.

The only way I see to remove or significantly mitigate the "contrivance-based" nature of TTRPGing is to broaden, vanillia-ize, or dilute a game's premise (which you buy into to play at all!), themes, and tropes such that it is barely recognizable as a thing...and then have super generic rules that don't perpetuate much of anything.

I think the model that has emerged pretty clearly in [MENTION=6775031]Saelorn[/MENTION]'s most recent reply to me is:

the GM supplies all the theme and tropes, under the guise of "worldbuilding" (thus answering your point 1); and,

the players play PCs who respond to those themes and tropes without injecting any of their own (thus answering your point 2).​

I use the word "injecting" deliberately - the player can build an elf paladin if s/he likes, but elfishness and paladinhood will become significant elements in play only if the GM - by dint of his/her "worldbuilding" - choose to make it so.

"Lets play a game!"

"Ok, what kind of game?"

"A game where you do stuff!"

"What kind of stuff?"

"Stuff that happens!"

"Ummmm...ok, what is the game about?"

"Whatever!"

"Ummmm...how do we make stuff happen in this game about whatever?"

"You tell me what you want to do and I'll just tell you what happens...maybe if you give me candy better stuff will happen?"

Well, it seems at [MENTION=6775031]Saelorn[/MENTION]'s table that "the stuff" is something made salient by the D&D rulebooks - so there'll be dungeons, but probably not family relationships - and the "whatever" is the GM's world, which the players will learn about as they go along. The burden is clearly on the players to just follow whatever cues the GM provides them with: so if the GM writes a story about rescuing captured elves, it's the players' job to write PCs who find rescuing captured elves a compelling thing. I don't know what happens at Saelorn's table if the players decide to have their PCs kidnap more elves on behalf of the "bad guys". (How do we even tell who are the "bad guys" without GM metagaming by just telling the players who they're meant to fight? I assume that's all taken for granted and implied via the alignment rules, the way the GM frames a patron encounter, etc.)

 

[Kobold Boots]

Pulling this back to the original discussion and perhaps being a bit too literal in reply.

An experience point is an arbitrary amount of work given out to represent learning on the part of a character during an adventure.
How much it's worth has much to do with the individual DM. They're not worth as much if they're given out like candy, and they're worth a lot more if they're given out frugally. Same with any other currency that you use to buy something (levels)

The issue of value is strange though in a closed market where there's only one thing you can do with a currency. If all XP are used for is to benchmark how close you are to gaining a level, then there are better ways to go about level advancement. It's just another fiddly bit that doesn't need to be calculated. Just gain a level when you hit a milestone. (in a team game it doesn't matter who lifted more stuff if the whole team survived and achieved together level them all - if someone died and didn't go through the majority of things, level them later - miss a milestone).

In an open market where there are a few things to spend XP on, then it makes sense that there would be a increasingly rigid experience system. When you gain enough expeirence you gain a level. Maybe instead of that level you want a new relationship/contact that can affect the game. Maybe you want a magic item. There are many examples of this sort of thing if you look around and find other game systems that are less level based; however, there's plenty of ways to house rule things.

Being very literal -
At face value 1gp - 1xp - I'm pretty sure that's 1ed/2ed only.

Being more open to things I'd allow if the players wanted it unanimously. Table needs to be in agreeance and giving up a level. Additionally, it's wise to keep in mind that giving up a level early on (level 2 at 300XP) is much different than giving up a level later on (level 20 at 55000XP)

- Dumping a level for an equal amount of gold.
- Dumping a level for a level appropriate magic item
- Dumping a level for a level appropriate favor or contact - given that there needs to be an in game reason for such things -

Things I'm generally against would be dumping a level for a feat or a stat increase. That tends to be overpowered or cause odd rules issues later on.

Another thought that comes to me as I'm typing this is that a character's experience point total can be used to assign a sort of cosmic value to the character. As far as the powers that be are concerned, Cosimo the farmer who might have accrued 15XP over the course of his life by shooing off kobolds isn't as important to the grand scheme of things as Cosimo the Paladin at 165,000XP or Alexi the Ranger at 23000 XP.

So in a world where Cosimo bites it and True Resurrection isn't available, if Alexi wanted to drop his eighth level of experience once earned for the favor of resurrecting Cosimo (because they're brothers or something and there's good plot around it) I'd allow it, but Cosimo would come back at 11000XP (Level 5) and have a lot of role-playing ahead of him and enemies to hide from.

Just some thoughts.

 

[Lanefan]

The issue of value is strange though in a closed market where there's only one thing you can do with a currency. If all XP are used for is to benchmark how close you are to gaining a level, then there are better ways to go about level advancement. It's just another fiddly bit that doesn't need to be calculated. Just gain a level when you hit a milestone. (in a team game it doesn't matter who lifted more stuff if the whole team survived and achieved together level them all - if someone died and didn't go through the majority of things, level them later - miss a milestone).

I disagree that it "doesn't matter who lifted more stuff" - I'd rather see the rewards go to those who pull more than their weight, rather than those who let others do the work. Otherwise the system counterproductively encourages doing less, and taking less risk.

Being very literal -
At face value 1gp - 1xp - I'm pretty sure that's 1ed/2ed only.

1e only. This was removed for 2e, largely because so many tables weren't using it in 1e.

Being more open to things I'd allow if the players wanted it unanimously. Table needs to be in agreeance and giving up a level. Additionally, it's wise to keep in mind that giving up a level early on (level 2 at 300XP) is much different than giving up a level later on (level 20 at 55000XP)

- Dumping a level for an equal amount of gold.
- Dumping a level for a level appropriate magic item
- Dumping a level for a level appropriate favor or contact - given that there needs to be an in game reason for such things -

Things I'm generally against would be dumping a level for a feat or a stat increase. That tends to be overpowered or cause odd rules issues later on.

Danger Will Robinson!

Anything where PCs can in any way trade in xp to gain monetary or magical wealth is going to lead to headaches that will unfortunately greatly outweigh the benefit (slowing your advancement down): they'll all end up way too rich.

There's perhaps an argument for going the other way - allowing wealth to be used to in effect "buy" xp - but I'm not a fan of that either.

Lanefan

 

[Kobold Boots]

I disagree that it "doesn't matter who lifted more stuff" - I'd rather see the rewards go to those who pull more than their weight, rather than those who let others do the work. Otherwise the system counterproductively encourages doing less, and taking less risk.

I'll agree to disagree with this thought, if only because regardless of who does what, the entire group needs to accept risk in order to accomplish anything. If someone isn't pulling their weight in one encounter it will balance out when they're the only person who can do anything to finish the next one. Of course, if the character isn't there then they don't get the benefit of passing the milestone.

1e only. This was removed for 2e, largely because so many tables weren't using it in 1e.

Thank you

Danger Will Robinson!

Anything where PCs can in any way trade in xp to gain monetary or magical wealth is going to lead to headaches that will unfortunately greatly outweigh the benefit (slowing your advancement down): they'll all end up way too rich.

There's perhaps an argument for going the other way - allowing wealth to be used to in effect "buy" xp - but I'm not a fan of that either.

Lanefan

I used to believe there was something as "way too rich" then I had a player that became a merchant on the side. Then all the players had mercantile interests and were all rather wealthy. All it really did was give them the resources to take on different levels of challenges and at the end of the day even if you have a well-equipped army at your beck and call, that doesn't save you from competitors and the random appearance of the burning legion (bad WoW reference made to make a point.)

End of day, it's about what you're willing to take on as a DM.

Be well
KB

 

[Lanefan]

I'll agree to disagree with this thought, if only because regardless of who does what, the entire group needs to accept risk in order to accomplish anything. If someone isn't pulling their weight in one encounter it will balance out when they're the only person who can do anything to finish the next one.

In theory this is true. In practice I find it's quite often - not always, but quite often - the same characters taking the risks over the long term and the same characters avoiding them. I'd like the system to encourage those who get stuck in, somehow.

I used to believe there was something as "way too rich" then I had a player that became a merchant on the side. Then all the players had mercantile interests and were all rather wealthy. All it really did was give them the resources to take on different levels of challenges and at the end of the day even if you have a well-equipped army at your beck and call, that doesn't save you from competitors and the random appearance of the burning legion (bad WoW reference made to make a point.)

End of day, it's about what you're willing to take on as a DM.

Yeah, I once had a group get into corporate dealings on the side. They ended up owning a couple of countries. Never again.

And the problem I find with having lots of wealth in the party isn't the wealth itself, but that it invariably ends up concentrated in a few long-surviving characters who are lucky enough not to suffer major losses along the way; leading to some rather wild imbalances that are really hard to remove once they get entrenched.

5e, like 1e and 2e, isn't as hung up on wealth-by-level as 3e and 4e were - but it's still possible to overdo it.

Lanefan

 

[The Crimson Binome]

Working together, here, seems to mean exactly "players who write their PCs to accord with the GM's world/plot", so that eg if the GM is writing an elf-kidnapping adventure then the obligation is on me to write a PC who will rescue elves, if I don't want my PC to be a bystander.

That is pretty standard AD&D 2nd-ed, mid-to-late 80s through 90s RPGing.

The most common two arguments I see on ENworld in favour of this approach are that (i) the GM has to have fun too, and (ii) anythinge else (eg improvisation, "no myth", etc) will lead to an incoherent and contradictory gameworld. But these are (obviously) both metagame considerations. What I don't really understand about your paritcular take on it is why you think it's all realistic and non-metagamey for players to build PCs who care about elves because the GM is all over elves, but terrible and verboten metagaming for a GM to build NPCs who care about elves because the players are all over elves and have (eg) built this group of elven PCs.

From a practical standpoint, creating a world requires a lot more work than creating a character, so the GM needs more time to do that and it would be impractical for the potential players to intervene at that stage. If you have a stable group in place before the DM starts creating the world, then there's absolutely nothing wrong with taking suggestions on what kind of world they want the game to be set in. If one of the players is tired of elves, then they could well reach a group consensus that the next game they play should take place in a world that doesn't have any elves, or where elves are extinct.

All of that is out-of-game stuff, though. It takes place before session one, or even before character creation. Meta-gaming isn't a consideration at this stage, because meta-gaming (by the common definition, rather than a technical definition) is only a meaningful term in regards to the actual game - how each character within the game world goes about the process of making their decisions. The main benefit of having the GM pre-establish the facts of the world instead of inventing everything as the story unfolds, aside from issues with consistency, is that it prevents the possibility of meta-gaming on their part. You never have to worry that the GM altered something to hurt you, or even to help you, if you know that it was written-in-stone before you ever got near it. (Failing that, you just need to trust that the GM isn't going to meta-game, which can be difficult in-the-moment when the GM needs to account for what everyone knows and doesn't know and compensate for their own anti-meta-game bias without over-compensating for it.)

 

[Kobold Boots]

In theory this is true. In practice I find it's quite often - not always, but quite often - the same characters taking the risks over the long term and the same characters avoiding them. I'd like the system to encourage those who get stuck in, somehow.

Yeah, I once had a group get into corporate dealings on the side. They ended up owning a couple of countries. Never again.

And the problem I find with having lots of wealth in the party isn't the wealth itself, but that it invariably ends up concentrated in a few long-surviving characters who are lucky enough not to suffer major losses along the way; leading to some rather wild imbalances that are really hard to remove once they get entrenched.

5e, like 1e and 2e, isn't as hung up on wealth-by-level as 3e and 4e were - but it's still possible to overdo it.

Lanefan

Hi Lane -

So on point one about players owning countries. I feel for you. I made that mistake once too.

Here's the deal though, any player with significant wealth who tries to disrupt the region's status quo is going to have a lot of people looking to maintain it. Being completely honest, that's the kind of change that will have NPCs of completely divergent alignments working together to prevent it. Real world mercantile guilds of massive wealth ran into that problem when nobles simply banished them instead of paying debt, and had the might to do so. There's absolutely zero reason why wealth should be allowed to pool in the first place, players will mess up if challenged in a way they don't plan for.

So I'd argue that every DM gets screwed once, then we get savvy.

On the point of "same characters avoid risk"

- Create an encounter where the party dies unless the super conservative character takes one.
- Make it obvious but not rail roady - there are tons of ways to do this on a dungeon crawl or exploration mission.
- When the party TPKs the other players will take care of it. When the party succeeds, problem solved.

The world isn't always able to be worked around. If you get blamed for rail roading the character in question, tell them that you can't always avoid everything, even in real life people get cornered into things. If you've got to go meta, there's supposedly tons of examples of the player not pulling weight.

To each his or her own.
KB

 

[pemerton]

Which in the moment is fine, but when there's no "big picture" behind it all you're stuck there in the moment - and all you can do is lurch from moment to moment. You as DM can't or don't or won't plan ahead such that some big event coming later can be foreshadowed or hinted at now

<snip>

not looking any further takes away all kinds of opportunity for mystery and long-term story.

We've had this discussion before. Everything you say here is not true.

Here are four mysteries that were signalled in the actual play reports I quoted in the post you replied to:

* Who killed the veiled alliance contact?

* Who killed 29's master?

* Why are Norhern Lights behaving strangely?

* What is the nature of Lt Li's bioweapons program?​

The Dark Sun game is about three sessions in. The first mystery is resolved - in the second session, a fourth PC was introduced as the assassin. The second mystery is still open. Furthermore, there is potential foreshadowing there - the purse with 14 gp may turn out to be very significant. (We don't know yet.)

The Cortex+ Heroic game is about fiwe sessions in. That mystery hasn't been resolved yet, as the PCs have failed to gather any significant amount of information about it - all they know is that the giant shaman has also seen signs of pending doom (this was the result of a player spending a resource to establish a social resource at the giants' court, as is described in the post that I linked to above).

The Traveller game is also about five session in. The mystery of the bioweapons program remains unresolved, but some things have been learned. Here's a non-exhaustive list: that there were agents of the program on the world of Byron; that Lt Li kidnapped and (it seems) infected a marine who was convalescing in a naval hospital (this was a PC introduced in the second session); and that there are Imperial officials who are suspicious of her activities and want them to be further investigated (this followed one of the players triggering a patron encounter roll, and the roll delivering a Diplomat as propsective patron).

And to step back from examples to the more general point: imagine if you (Lanefan) read a post saying it was impossible to run a successful D&D campaign that ran for more than 5 years. Or that involved conflict between PCs. You would think those claims were absurd, because your own play experience is of (successfully) running and playing in campaigns that run for more than 5 years, and include conflict between PCs.

Well, that's how I respond to your claim above, which frankly comes across as based purely ignorance. It's not that you've tried to run a game in the way I'm describing and found it hard to have mysteries or complex storylines. You're just speculating. And I'm here to tell you, on the basis of actual play experience, that it can be done and it's not very hard.

If there's no secrets, what's the point? There's nothing to discover

This is also just wrong.

Here's something to discover in my Traveller game: what is the nature of Lt Li's bioweaons program? That's unknown. But it's not a secret, because I - the GM - don't know either.

Here's a more banal example from the same campaign: what sorts of vessels do the bioweapons conspirators have access to? In the first session, all we knew was that they used to have a yacht, but then (as part of his backstory) one of the PCs won it from them gambling. (This was the backstory that explained the noble PCs ownership of a yacht.) Hence the reason that Lt Li had to recruit the players to ferry materials from Ardour-3 to Byron - it was the PCs who had the necessary ship!

In the fourth session, it became clear that the conpsirators also had access to another vessel capable of firing on surface targets from orbits. It was established that this was the laboratory research vessel St Christopher. (Which I had taken from an old White Dwarf adventure, Amber to Red.) I decided to introduce the St Christopher into the game after generating a NPC - an ex-naval forward observer - on my bus ride to the house of my friend hosting the session. I was driven by two thoughts - I thought it would be fun to test out the directed fire rules; and I thought having a NPC call down directed fire onto the PCs would drive some action and decision-making, which would prevent the game bogging down in investigation and indecision at the bioweapons outpost the PCs had taken over at the end of the previous session - and the debates at the wind-down of that session had made be a bit worried that the players might get bogged down. As it turns out, my plan to force some decision-making worked; and at least a couple of the players also found the "drive our ATVs across the barren world trying to avoid getting blown up by laser fire being called in from an orbiting ship" epsiode exciting.

Then, in the most recent session, as the PCs were departing from their orbit around the world that is the source of the bioweapons conspirators' pathogen, the starship encounter roll turned up an encounter with a pirate patrol cruiser. The PCs decided to intercept this cruiser's communications (I can't now remember why - I think the players were supsicious of a cruiser turning up on a fairly isolated world uninteresting for anything but this pathogen) and learned that it had jumped from Olyx, Lt Li's base world and the PCs next intended destination. The decision to have the "piratical" nature of the cruiser be its connection to the bioweapons conspiracy was mine, as GM - made on the basis of the principle "Always go where the action is." It established that the conspirators also have access to a patrol cruiser (not too surprising given the strong involvement of Imperial marines, naval and scouts personnel that had already been established in play); and it prompted discussion over what will probably be the main focus of next session: do the PCs try and take control of this cruiser for their own purposes? (Here's a thread I started to get advice for my players on this question.)

The general point: there can be systems and methods for introducing new content into the game that don't require the GM to have authored it in advance. Random encounter checks are one; scene framing techniques are another (and the previous two paragraphs you how you combine these two - "indie"-style Classic Traveller); the sort of system that let the player introduce the giant shame into the game is another.

The DM makes a game world (and by the by, a rule system), populates it, puts stories and adventures and what-have-you in it, and away we go

That's one way to run a game. My point is that it's not the only way.

The group of armed and surly-looking men, for example. You as DM can have them just be a random bunch of toughs, or they can be members of or hired by a gang whose toes the PCs have unwittingly stepped on (setting this gang up as later opponents or long-term villains), or they could be there as a distraction to allow someone to stow away on the PCs' ship (again setting something up for later). The players (and characters) don't and shouldn't know at the meta-game level whether these men are a random interrupt or part of something bigger; they just have to deal with the moment. You as DM, however, can juggle all sorts of things behind the scenes; and it makes for a better game if you do.

This is very obvious. Notice also that I don't have to decide anything about the NPCs at that particular moment of play in order to do this.

Also, "juggling things behind the scenes" just means "keep various possibilities in mind when later deciding what would be an interesting thing to introduce into the game".

Having all the backstory be pre-known by the players

I have never said any such thing. I have said that the GM does not use secret backstory as a factor in adjudication.

To give a concrete example: when the player wants to spend a resource to establish (in the scene) a giant shaman who is sympathetic to the PCs' cause, under my principles I'm not allowed to veto that action declaration on the basis that there is no giant shaman there.

Here's an example of some backstory that wasn't know by the players until they discovered it in play: Lt Li is a bioweapons conspirator (the players discovered that when the PC spy seduced her, and successfully interrogated her, and I had to make up some stuff for her to tell him); the bioweapons conspiracy is based on the planet Olyx (I can't remember excalty when I made this up, but I think it was introduced after the PCs took over the research outpost on Byron and interrogated the people they had captured there); the bioweapons conspirators have access to the various vessels I menteiond above.

The difference between authoring in advance and authoring in response to player action declarations and other discussion and interaction at the table is that the former is (in my view) railroading, as it is the GM who establishes all the possibilities and outcomes of investigation and action; whereas the latter is a collective endeavour ini which the fiction that emerges contains elements resulting from the contributions and participation of everyone at the table.

having no predesigned world at all, with the whole thing instead being some sort of Schroedinger's Universe, is even worse - I want to know these things in the game world would be the same if I explored it again tomorrow with a different party after having not explored it today.

That's a statement of preference - you would rather have the GM read you his/her notes than participate in jointly creating a shared fiction - but it doesn't show that the latter can't be done. (By the way, I don't really follow "Schroedinger's Universe". The imaginary universe doesn't become more "real" because it was written yesterday rather than today. The Schroedinger phenomenon in particle physics is interesting and surprising because one generally takes the real world to have an existence and character that is independent of human interaction with it. But no one but a child would suppose that imaginary worlds exist indpedently of their human creators.)

Or a made-up-on-the-fly series of events, and if I'm doing it right you-as-player won't be able to tell the difference.

Well, they might tell the difference because they can see that their contributions are having an effect on the content of the shared fiction. In any event, I don't know why you would do this, given it seems to contradict the very strong preference you state in the sentence I quoted just above.

 

[The Crimson Binome]

The imaginary universe doesn't become more "real" because it was written yesterday rather than today.

It does become an objective place, though, which is important. It exists the way that it exists, free of interference from outside of that universe. It demonstrates basic linear-time causality. I don't have to be afraid of changing its past, based on any of my actions in the present (short of time travel).

And in that sense, it does become more real. It may never be entirely real, because it's still just an imaginary universe, but at least it becomes a believable imaginary universe. Every conceivable universe worth exploring must demonstrate internal causality, and if you don't even have that, then what remains is not worth buying into.