All hail the powerful Summa

Starting this thread so as to not derail Erik Tyrell's thread anymore than I already have. Touches on a subject that I've mentioned before (Breaking Summae), that Summae are paths to ultimate power in Ars Magica. Couple that with the amount of tractatus having been written (and therefore some large percentage is probably available) in What is a sound tractatus thread, we have an Order that never needs to study from vis to reach Archmagus rank in an Art, let alone nearly all of them.

They are fundamental collections of information with so much information contained therein that they are a primary tool for advancement for everyone up until around level 20, if they can get their hands on those books. What they are described to be in the game and how they affect advancement are two markedly different matters, though.

Most times, if I'm part of covenant creation or if I'm acquiring books in play, a L20Q10 summa is going to be much more attractive to buy than say 4 or 5 Q10 tractatus would be. Only if my Arts are close to 20 (19, really) am I going to pick tractatus over the summa. In play, the pricing of a L20Q10 in play is a bit of a gray area, some might call it a vain book, and charge only 10 pawns of vis for it; and compared to the 4 or 5 Q10 tractatus is nearly equal in price, and would provide a lot of benefits to the rest of the magi of the covenant who aren't as skilled in that Art, but would like to be.

Good idea moving the thread. :smiley:

I think you mean a L20Q10 Summa, not tractatus. That would require an author with an Arts score of 40, which would not be common in the setting I prefer. Such Archmages with decent communications scores to write high quality books would be even less common. When such books do exist, they're rare and closely guarded secrets, not market commodities.

YGMV, of course, but this feels more wizardly to me than the "piles and piles of texts" approach often cited as a quick path to power.

Corrected the post for summa, not tractatus. Thanks.

What is the typical summa that is available to characters in your game? The only guidance on this from the line is that the combination of Level and Quality not exceed 31 when purchased with build points. There's a bit about Branches of the Arts being the best available and not every Art has a branch written for it. I know The Lion and the Lily has one defined that is L+Q=31. There's the hook that pushes that combination to 35, IIRC.

Jonathan, I'll return to you a question that you often ask to others: What is the problem you are trying to solve? :wink:

There are many avenues that one can take to modify how book advancement is handled. Depending on the problem you are trying to solve, different changes can be suggested.

Are you trying to reduce the prevalence of summae in a magus' advancement throughout the years? To replace it by what? Tractatus or vis? Or something else?

In this particular instance it was to continue discussion without derailing a topic. I've satisfied myself on how to limit summae; the problem is solved for me. I was trying to understand why Jabir and whomever originally proposed it want to limit Tractatus to be the result of experimenting in a Lab Activity.

My experience is that characters grind on summae until they can't. And then do other stuff, but that other stuff isn't generally vis, and even though covenants wasn't meant to be representative of an economic system, it's often used as one. Tractatus that are sound (IMO Q9 to Q11) cost a couple of pawns of vis, and based on the work you did in my other thread about What a sound tractatus is, there are quite a few of them... So, if a character grinds on a L20Q10 summa and then begins consuming tractatus, and there are many as you hypothesized, you can basically get to Archmage levels pretty easily...

But really, the goal here is discussion in a place that doesn't derail another thread.

You're looking at it from a mechanical "which is more effective and needs nerfing" standpoint. From a thematic standpoint it makes perfect sense that tractati, which detail unique insights, would require some source for that unique insight (whether that be from experimentation, adventure, or the combination of uncommon knowledges [someone with a score of 3-5 in profession: blacksmith writing a tractatus on terram for instance).

There's no thematic reason to limit summae in that way, as they aren't meant to contain unique insights.

Why is there a thematic need to limit tractatus, then? Are we saying that someone with a particular score in an Art or Ability knows exactly the same thing as everyone else with that same score?

If they got that score by studying under the same teacher, or reading the same summa (aka the roots of the arts) then they will.

Personally I think that studying from vis, and learning from practice/exposure, are sufficiently common that most people will have unique insights, so it's not worth tracking the edge cases where they won't. But it's reasonable to rule the other way; that mere practise and exposure don't provide anything that won't be found in a standard summa, and it takes a deliberate effort to gain such a unique insight.

Minor niggle, you can't practice Arts, the analog for that is using Vis.

But, how often have any of your characters actually studied from vis? Studied from vis when a high level summa was available?

This has been true for a long, long time. Even in 3ed, and 2ed once Twilight was introduced, reading was far better than vis, especially since authors were not always limited to Art/2 if they gained Increased Understanding. Books at level 30 were quite reasonable.

I might even say that summae are not as good as they once were, since a score of 40 is needed for a text at 20. That's 820xp. Even with an Affinity, the ~550xp needed is still extreme. A summae at level 25 is thoroughly unlikely, and is a reasonable limit of what has ever existed.

The biggest issue, I think, is that studying from vis is a lot more expensive in this edition. Back in the day, a single pawn sufficed, and no more than 3 pawns per season were allowed.

Tractati are a larger issue, I think, because they remove caps on Art scores. If the game only had summae, scores would be limited to 25 (and we'd need a good answer for how such texts exist at all.) If the game only had tractati, the sky is the limit. Sure, it takes more tractati than summae to reach the heights, but every unique tractatus helps get you there. The Order might easily be awash in them (prove your TeFo of 35 by publishing 7 appropriate tractati...) Any newly Gauntleted magus with a score of 5 in one or more Arts is useful to older magi. Sure, most of these will be vain, but an elderly magus with an Affinity in an Art at 40 or so still gets a decent season to push that Art even further. Summae are just an efficient avenue for saving better tractati for later.

Never. Then again we only have two particularly high level summae, and neither of them are on arts.

In a saga where high level summae are available with ease it would make no sense for them to be able to write tractati without adventure/experimentation; everyone else has read the same summae they have, what's the insight they're including in the tractatus?

For various reasons [both setting and houserule] that's not true in my saga.

Kingreaper, how do you advance Arts, then? Your house rules and setting don't have high level summae? How many tractatus exist in your library?

High level summa (is plural the same as singular?) allow easy advancement to very high art scores. Having scores in the 17+ range allows for spells in the 40+ range. This doesn't fit my model of what should be doable with easy advancement.

I'd like to see summa cap out at level somewhere in the range of 8-12. I think that it would be an improvement to make the max level possible for an author to write at equal level that the author has in the art/3 rather than level/2. I also think that it would lead to better games if the cost for summa (in covenant) build points were closely related to how many xp you can pull out of it, or if that's too number intensive, make the cost go up dramatically after some moderate level (8?).

Plural of summa is summae, and the plural of tractatus is tractatus.

I like the idea of summae, of being really dense pieces of text that require the aid of an instructor to use effectively. In Stealing the Future, I also proposed having a summa be an aid to learning from Vis by up to twice the level of the summa, highlight it's utility as a reference text. But generally, I'd like to reduce the availability of summae in practice while making other methods of advancement more attractive, because right now, the summa is far superior to almost any other method, up to a level limit of about 20.


It makes sense for progress to be very easy up to a point. Many students graduate high school knowing physics that took 1000 years to develop, without having to refer to a single research paper or book beyond their textbook. They aren't smarter than Galileo, but they have a much better summa :slight_smile:. That is, the state of the art has improved over the years.

It would be entirely reasonable to establish limits for various Arts and Abilities that cannot be transcended merely through study, or even practice or adventure. A summa can get you halfway to that limit, tractati can get you all the way. After that, you or someone else needs a minor breakthrough, or something like that.

The state of Brawling in ME might not be that developed, but if Marco Polo returns from Mythic China having learned Mythic Kung Fu.... :slight_smile:



But all along the way, whenever you have a textbook (summa, to me) you have a teacher helping you dissect the knowledge in the textbook and turn it into useful information. Some people are capable of doing all of their learning from a textbook (these are book learners) and some learn best when taught by a teacher (these are Apt Students), and some with dyslexia might not even be able to read a book well, depending upon the severity of their dyslexia.

What are the reasonable limits for Arts and Abilities that cannot be surpassed with additional study, adventure, practice? Why is studying from vis different than practice (it's the analog for it since one cannot practice the Arts). How does one achieve this minor breakthrough to transcend and break past the limit, and once they've done so, can they advance with tractatus again?

Since I'm not actually playing at the moment, I don't have a real answer to that. It's more of a general sense of how I see the setting I would favor, with a fairly low density of extremely experienced magi and an Order that is more oriented towards secret knowledge than towards the model of either modern academe or a marketplace.

I'd never actually seen the tractatus/experimentation connection before. My reaction was primarily thematic, for the same reasons kingreaper gave in an earlier post, but also driven by my perception that the system for tractatus is broken and needs some sort of fix. My own preferred fix has been to assign a level to each tractatus equal to the author's level in the skill (not level/2 as for Summae), but there's something very appealing about the experimentation suggestion. One problem though is that it would be hard to apply outside the Hermetic Arts.

Summae are fine as is. The level cap keeps them reasonable in game balance terms and the fact that they cover the same basic material means that there are likely a limited number for each Art, which can thereby be given flavorful descriptions and author details.

Tractatus, on the other hand, usually are nothing more than lists of source quality, perhaps with a brief and forgettable author/title, perhaps even omitting that. The quantity that tend to exist in libraries make it hard to go beyond this level of detail. Mechanically, the lack of level restriction makes advancement too easy and leads to various twinky possibilities, like having all the apprentices in a Covenant write tractatus in round-robin fashion.

Generally I would like books to have unique character and flavor, as for example in Lovecraft, and for libraries to be reasonably sized and composed of rare and valuable volumes, not piles and piles of research paper equivalents. I'd also like progression in Art beyond some certain level to be difficult without studying from vis or actively seeking out exceptional books or Archmagi teachers.


Yeah, you have a better teacher to go along with that better text. My AP physics teacher didn't get to put points into Inventive Genius, Mythic Intelligence, etc, but maybe has more points in Com and Teaching. (And the physics text was written to have a higher quality, so that students might better understand. That hasn't worked out as well as one might hope IRL.... :/)

As for the limits themselves, I think that would be saga-specific. YR7's saga might have limits of 10 for Arts. Marko's might have 35, with Ignem being special at 45 because Marko likes Flambeau, and Aquam at 30 because who bothers to specialize in that? I suspect that a starting limit of 20 or 25 (maybe 15 for some people) is a good swag.

I see practice as very different from studying from vis, because practice is safe.

Studying from vis is more like experimentation, because you can botch, big and nasty. One rules change might be that studying from vis returns to allowing a much smaller amount of vis to be used, but requiring a roll on the experimentation table. As usual, the base experience gained is simple die + risk factor (and maybe +Aura, since that's already in a normal lab total and adds to botch dice), but if the table says the experiment did nothing useful, the base lab total is 0, no effect. A different rule might require a minor breakthrough to increase an Art score by one.

A magus who advances the SOTA can disseminate his discovery by writing a tractatus, which other magi can read to raise their personal limits. He can also write a summa, which, if fully read, does the same. Magi who have absorbed the insight can also write texts. The summa is better for a young magus, and the tractatus better for his elders, as usual.

My own observations on Summae mainly comes from the various discussions we've had on Roots and Branches - if we assume that a 6/21 root is a reasonable maximum, that means that someone with 27 "points" of writing ability has existed at some point in time in the order, and has written a basic primer with nothing but their own TeFo ability + Com + Good Teacher (if any).

That same person can also write a Branch, using their 27 points of writing, and get a nice binding (+1) and some nice pictures (+1). For convenience, I also assume that at one point, there was at least 1 writing savant in the order who had a better Com+Good Teacher score (as well as the requisite minimum Art scores), and did an edit/commentary pass on all of these (for another +1). That gets the entire score to 30.

Which means that a Branch can be anything from a 20/10 to a 15/15 to a 10/20. Personally, I like 15/15 as the default, with some being more advanced (17/13), and some being more basic (12/18) - with students generally preferring the easy-to-read tomes with lots of pictures (12/18), with the more advanced magi preferring the more "dense" texts (19/11). For the more popular Arts (Corpus, Vim, Ignem), I would imagine there are a few unofficial Branches of Differing level and quality.

I actually did a bit of a spreadsheet experiement - trying to find out what the most efficient advancement scheme would look like, assuming an optimum Quality/Level of books written at different levels. I was also looking into the actual advancement benefit for things like Book Learner. Unsuprisingly, it turns out that if you have an optimized book tree, things like Book Learner don't actually help all that much. (I think it was a season or two saved over the course of 12? seasons) The less optimized the book tree, the better, though.

Oh, and the reason I liked the "you must experiment to make tractus" rule was simply thematic, as well as a way to avoid the implied "tractus writing circle", whereby 5 magi can write themselves up to archmage level simply by trading recepies for a couple of years.

I actually don't have a problem with the concept of a group of magi trading tractus... it just felt a bit too easy, IMO. Again, this was a thematic/stylistic thing, for me.