GoF p. 55 states that visitors of the Great Library are not allowed to copy books without the explicit permission from a librarian.
I'm slightly baffled by this. What is the rationale? I cannot think of a historical one (excepting anachronistic ideas about copyright), and dissemination of magical knowledge among its members is very much in the interest of the Order, so I'm assuming this is a game balance measure? Are book rules broken enough that allowing copies of the "greatest summae" a horrible idea?
Also, the description leaves the authority of the decision open. Is the permission on the discretion of individual librarians, are there guidelines to follow, or what?
(Actually, I have to say that while GoF has lots of nice stuff it is also driving me quite mad with bits and pieces like this, which are too specific, and yet not specific enough. Instead of saving work, it creates more. :/)
Knowldge is power, and also currency. If people were allowed to copy the books in the great library for free and whenever they wanted durrenmar would lose it's prestige and a large income. They charge for studying and copying their books, and the best books are never given out, only charged a fee for studying from.
I imagine another factor is that the reason for the Great Library's greatness is the requirement that users must contribute to the library in order to use it. If copies of its books were to get into general circulation, there would be no incentive for users to contribute to the library, and the library itself would die out.
I presume that the idea is that the Great Library charges for copying, and does not allow copies of its greatest works, as a way of making money. This is not that unusual an idea, historically, although its bad librarianship. Really, really bad librarianship. If I was the Primus of Bonisagus I'd be tempted to fire these people, because the whole point of the House is to preserve the advancements of the arts, and making sure there is only one copy of the finest set of books, and putting them all in one place, is guaranteeing that they will be lost in a single tragedy, and that the descendants of the magi will cry for its loss much as members of the Order do for the Library of Alexandria.
When I was writing SoI, I did include a backup copy of these finest books, hidden in the Cave of Bonisagus in the Alps. It was based on Second Foundation, by Asimov, but people thought it was "Men in Black" so it got cut - all except for the illustration of the guys with the symbol of Omega (looks like a horseshoe) on their jerkins.
I presume some future book will make clear that there is an external repository for the finest works in the Great Library - for me the lack of one is a breach of versimiltude.
I was going to say that the idea of "don't allow copies because then you're not the biggest library any more" doesn't scan: people are still required to contribute in order to use the library, and copying a big summa should take longer then just studying it for a season -- so every time someone copies one of your summae, you get several books in return.
However, looking at the rules, this isn't so: you can copy any 1 tractatus or 6 + Profession (Scribe) points per season, towards the Level of the summa. So a decent scribe has no trouble copying almost any summa, and by definition can copy any tractatus in a season. Add to that the fact that a contribution to Durenmar lets you study for two seasons...
So with the rules as written, no-one would study any summae in a library if they were just allowed to copy them out -- it makes much more sense to have a copy to take home for several seasons of study! Doh.
As you note earlier, historically it is quite common for big libraries to forbid copying. I don't think it breaches verisimilitude, but it's certainly a failure of rationality on the part of House Bonisagus.
Sounds like a great character goal for a player character Trianoman.
As a general note, I'm quite deliberately trying to make sure that the Order is not optimised, and has illogical customs. A perfect system is better for living in, but an imperfect system has more space for roleplaying, because there are things that need fixing. Ditto for Hermetic magic; there are some things it's bad at, because those are good material for breakthroughs, and breakthroughs are good character goals.
Do you happen to have a reference for this? I don't claim to have looked low and high, but I have spent a while --- and from my general familiarity of history of copying (and ideas leading up to copyright) this is the first I hear of anything like this prior 17th century.
Saint Columba goes as a missionary to the picts in penance for leading his relatives in battle with pages from copies of a bible as standards. He does this afer he is told to hand the bible over to the monk who he copied it from, withough his permission, because for every cow its calf, for every book its copy. That is, you own copies of your books. This is the earliest copyright I've found. It's the source of the Cow and Calf Law in "Covenants".