Like a lot of ArM5 players I've always thought that study from Vis was kind of crappy in this edition. Not worth the warping and a little expensive in both vis and time.
Then I built a Study from Vis simulator using Google's Blockly app. https://blockly-demo.appspot.com/static/apps/code/index.html#6zcfoy. It took me a while to really trust that it was working right. The results were a little surprising. The program might still be off but I've gone through it pretty carefully, run some dice and paper simulations, and done some back of the matchbook math. It all seems to confirm a few things.
Vis study can be...
...very vis intensive particularly at high levels.
... less time intensive then other study methods when done in a high aura.
... far less risky when it comes to warping then I ever thought.
For instance going from 0-20 in a lvl 10 aura takes about 14 seasons and costs around 40 pawns of vis. About the equivalent of studying from an exceptional summa (L20Q15) from Covenants. But what about Warping? Well on average you should get about 0.4 warping points. Or to put it another way, it's not likely you'll accumulate much if any warping. (Every pawn spent has a 1% chance of causing a point of warping. So if you spend 100 pawns that's an average of 1 point of warping though there is a pretty high standard deviation)
Dropping to a more average aura of 6 raises your costs to seasons≈19 pawns≈55 warping ≈0.55. Still I think that is a bit better then 209 points worth of tracti or the best single summa you can buy with build points (Q20L11) in the basic book.
Getting to larger number makes the costs rise 20-40 in a 10 aura. seasons≈40 pawns≈270 warping ≈2.7
But all that's without learning virtues or corespondences. Once you add them costs can really drop. A Self Study with a PenPal an affinity and a great aura can go from 0-20 in 8≈seasons spending 20≈pawns gaining 0.2≈warping. Going from 20-40 is seasons≈21 pawns≈135 warping ≈1.35.
Again I might be off. But I think these numbers are close to correct. As such this has interesting ramifications on some of my assumptions about the Vis and book Economy and just how common Vis study is order wide. Not to mention the value of high level auras and the Free Study virtue.
That's some good work. Although the core book suggests that Aura 3 is more "typical" (ArM5, page 32). Which, assuming I am driving your code right, seems to increases the time to get to a Score of 20 to the mid-twenties (worth of seasons) and the cost to around 70-80 pawns.
In play, it always seems that there is something much better to do with vis than study it (cast Aegis, cast other rituals, make Longevity ritual, enchant items, etc) and vis is expended when you study it. The cost of vis use will depend on the availability in the saga, I guess, but it will always be significant that there is only one thing that you can do with a book (read it or perhaps copy it), and reading a book doesn't prevent your sodales from reading it when you've finished.
So vis study might look attractive for isolated magi, with nothing to do, and lots of vis. But, that seem a bit artifical. In-play magi generally have got other things to do that require vis, and have sodales who they must compete for vis with and can share books with. So books, I think, look much more useful in "realistic" circumstances.
Thankyou. And your right the book does suggest 3 as typical. I was just going with the far less reliable play experience. Still I assume not every Magic aura has a Covenant in it. And it might not be too hard for an experienced Magi to find a 6+ aura safe enough to spend a season studying.
Agreed. But there are other types of Magi Vis study is attractive to. Effective books eventually run out. I assumed elder Magi would shy away from Vis study for fear of Warping. But as negligible as warping can be it stays a viable option and sometimes the only option when books get scarce. Not to mention the potential time savings. Yes it's expensive but older magi can more afford it. So powerful older magi have another drain on their vis stores. Among other things this might actually raise the value of new books.
Studying Vis for low Art scores and early in the career is probably worth it. It's a big bang for the buck, when you can expect to get ~6+Aura experience points. For Art scores of 0 it makes a lot of sense to study from vis if you don't have the L5Q15 or L6Q21 summae available. When you get to the middle level the 6-10 it is a tougher call.
I do think that while aura 3 may be the standard, PC covenants probably have higher and furthermore find locations with a higher aura (and you don't need to study raw vis in your lab). So for a PC a higher aura does seem reasonable to me - not 10, but perhaps 6.
Another advantage of studying from raw vis is that you get to pile both Free Study and Study Bonus. Now granted, you can pile on Book Learner and Study Bonus, but that feels less appropriate to me. You can initiate Study Bonus though a Bjornaer Clan Mystery, or gain it by walking a Forest Path, and it makes sense.
It requires substantial amounts of raw vis, but not astronomical amounts that are clearly implausible. And the chance for Warping is indeed rather low. So overall, I think it's a great way to learn Arts. I think it was the main way in the early Order, before there were ample books, and is still the main way for elder magi, who've run out of good books but have lot of resources, and for mystics such as many Bjornaer.
An aura of 5 would be a good realistic benchmark IMO, since most PC covenants I have seen have this level of aura.
In our manx saga we were basically living in a vis oil field. we used vis quite consistently at low levels and it was worth it. However, when we were hitting the high levels we tended to switch to tractatus because of the warping risk; our magi were more experienced and more wary of the warping effects of vis on them. The players were also more wary: in the early stages of the saga we did not know if the saga would flop or not, and we were more reckless with our characters. As the saga developed and the commitment increased, caution to preserve the characters was on the rise.
The "low level = use vis" approach also has implications for the OoH. Maybe Summae up to level 10 are not that common, simply because you can substitute for them using vis easily. Never thought about that, but it makes sense. You get tractatus, great summae or vis. Mid range summae seems extremely bad choices here.
The numbers seem quite right, and I agree it was probably the method of choice in the early Order (say, the first century or two of its existence). A stress die averages roughly 5.5, so vis "Quality" is 8.5 (that of a lowish Tractatus) in a +3 Aura, 10.5 (that of a sound Tractatus) in a +5 Aura, and 13.5 (that of an exceptional Tractatus) in a +8 Aura like that of Durenmar. Study in a magic Boundary, or an Aspected Aura, can give truly phenomenal returns; as can study from Infernal vis if you have Chthonic Magic, if memory serves me well. Warping is also not that high (what really worries my troupe is the chance of a double+ botch and Twilight, even though with an Art Score of 25 it still has less than 1% chance of happening).
But in the current state of the Order, for most Covenants books seem a better option. Roots give you Quality 15 or higher; but so do most Summae traded within the Order with Level 13 or lower (since according to Covenants, most summae traded have a Level + Quality of 28 to 31). This beats any vis study from a (simple) Aura of less than 10, and you generally need an Aura of at least +5 or +6 to make it worthwhile even at higher levels (assuming spending half a dozen pawns is no big deal for your characters). Another thing that is oft disregarded is vis study's Quality is unpredictable, so you can't plan well on it (as you can with books: "I'll study this summa for 2 seasons, and then that tractatus for 1 season, which will bring my score exactly to the level I need to invent that spell before the year is over"). I've never seen study from vis in my 5th edition sagas, except in situations where magi were stranded in some remote place without any contact with Hermetic civilization.
First of all, I would always pick summae first, simply because they can only be used up to their level, and can be used repeatedly to that point.
If summae were not available (isolated covenant, ancient order, whatever reason) then the fact that a sound tractus costs 2 vis, and studying from vis costs 1 per 5 levels or fraction thereof, You might study from vis, given those two alternatives, until you reached level 11, then the tractus would be the better buy. A vain tractus would cost 1 vis, if you have a low aura and your level is above 6 it could easily be easier than studying from vis.
Studying from vis is better for the individual than for the covenant. Book costs are spread among all of the members of the covenant, and 10 xp from a tractatus is available to anyone who reads it, at a cost of two pawns. Whereas 2 pawns of vis in an Aura of 5 might be worth 11-22 xp on average for the individual and Art Scores.