Unseen University (UU) is a school of wizardry in Terry Pratchett's fictional Discworld city of Ankh-Morpork, staffed by a faculty composed of mostly indolent and inept old wizards. The official motto of UU is "Nunc Id Vides, Nunc Ne Vides", loosely translated as "Now you see it, now you don't". The unofficial motto is "η β π", or "Eta Beta Pi" (Eat A Better Pie). The university's name is a pun on the real-world Invisible College.
The coat of arms is azure, a livre des sortilèges, attaché en cuivre, sur un chapeau pointu. (That is: a blue field bearing a book of magic spells, with copper clasps, over a pointed hat.) As usually rendered, the coat bears a strong resemblance to the coat of arms of the University of Oxford.
The University is centred around the Tower of Art, out of which it grew; any further attempt at grasping its geography is close to pointless. Due to the high levels of background magic in the vicinity, a typical map of UU vaguely resembles an exploding chrysanthemum and is usually only valid for a day or so, though it is generally agreed that the inside of UU is larger than the exterior walls, under normal circumstances, should be able to contain. This is also the cause of the various physical and biological anomalies that plague it. In some rooms the direction of gravity moves around as a day passes, and some rooms contain other rooms which contain the room one started with (especially problematic for a conga line). The University's gargoyles have taken on a life of their own (not that this is anything unusual for Discworld gargoyles in general). Both a colony of ants in the main university buildings and a flock of ravens roosting in the Tower of Art show unnatural intelligence and, for the ravens, an ability to speak, again, common for entities associated with the University. The fabric of the University is said to absorb knowledge, since all students enter university knowing absolutely everything, and leave admitting they know very little.
One of the most notable rooms in UU is Room 3b. This room is not believed to exist, but a surprising number of classes are scheduled there. In fact, at times of great celebration in the city of Ankh-Morpork it is not uncommon for the entire faculty to be teaching there.
After learning the basics of spellcasting, UU students are challenged to continue their research in the Library which, like the Bodleian Library at Oxford, features chained books - although at Oxford this is done to protect the books from the students, whereas at UU it is done to protect the students from the books. The high concentration of magical lore has warped the Library interior into a locus of L-Space where the concepts of distance and direction are only vaguely defined (it is generally described as resembling an M. C. Escher pastiche of the Bodleian or the British Museum Reading Room). There the students will encounter the Librarian (transformed into an orangutan by a magical mishap) and seek out the grimoires binding the more formidable spells. Since the contents of all libraries are in L-Space, it is possible to enter a Library in one city and exit in another. Access to libraries of other times or other realities, however, is at UU restricted to the Librarian himself.
All citizens of Ankh-Morpork are entitled to visit the library, although non-magic users will generally never find their way beyond the more mundane shelves.
Forming much of the border is the main building, with the garden known as the Main Octangle in its midst, the Clock Tower housing Old Tom (the University's tongueless octiron bell whose strikes make "anti-noise" that silences everything briefly) and a connecting outbuilding linking it to another complex further rimwards that may or may not be University property. The rest of the rimwards border is supplied by the Observatory. Turnwise and somewhat hubwards of the main building lies the Library, housing the largest collection of magical texts known on the Disc; in accordance with L-Space theory, every book ever written anywhere may also be possibly found there, as well as books that might have been written, books that were not written and books that have yet to be written. Further hubwards of this, joined by a small connecting building, is the outer hubwards wall, with the High Energy Magic building recently added. The spot between this building and the Library is the workspace of the University gardener, Modo, a genteel dwarf who was nearly eaten by his own compost pile. Beyond this is New Hall, also connected over the wall via connecting buildings. Further Hubwards lies the Unreal Estate, which used to be the University's landfill but nowadays has been sold on and developed, especially by the budding thaumaturgical industry. The park-like surroundings created here are marred by the extreme amounts of background magic emitted by centuries of accumulated magical waste.
Inside the walled complex are the main University Gardens, with the Tower of Art in their midst and two boathouses with jetties, occasionally used by the University's watersports enthusiasts. The University holds rowing contests, but because of the normal state of the Ankh, these usually amount to a jogging/sprinting race on the crusted surface. Entering the gardens over the Ankh is the Bridge of Size, which connects to the Wizard's Pleasaunce, another small garden on the Ankh's turnwise side walled off from Hen & Chickens Field and possibly also gated. At one point, in the novel Sourcery the Pleasaunce contained a temporary new headquarters for the magic-addled staff of the University.
Entrance and exit into the complex is by one of the gates, which probably number at least two (one in the main building facing Sator Square is likely, but not certain). These gates close in the evening, and students who like to get out after this have created an alternate opening known as Scholar's Entry. This is a place in the wall where bricks can be slid out to form a usable ladder, and has always been known only to students. However, many students forget that all the staff were, in their time, students themselves.
It was reputedly left behind, with characteristic absentmindedness, shortly after the Creator completed his major work. The Eight Great Spells that initially made the Discworld are imprisoned on its pages, giving the book sentience.
It somehow came into the possession of Unseen University, where it was stored in a little room off and under the University's Library. Given the nature of the book, the room is full of precautions; not so much for the protection of the book as much as for the protection of its visitors. The walls are covered with protective symbols and lead octograms (a reference to precautions taken to shield nuclear reactors; Pratchett once worked for a power generation company). On the floor is the Eightfold Seal of Stasis, generally considered in magical circles to have all the stopping power of a well aimed half-brick. Even with all these measures, no one may stay in the room for more than 4 minutes and 32 seconds, a figure deduced after two centuries of cautious experimentation. It also seems likely that the Octavo is more than capable of ignoring these precautions, as it would seem that it did just that to allow Rincewind access to one of its spells (see below).
The Octavo is attached (perhaps a more accurate term would be "tethered") to a lectern in the shape of an unpleasant winged creature by a very heavy chain fastened by eight padlocks (one for each Head of each Order of Magic). It is also held shut by metal clasps.
While on his first year at the University, Rincewind the wizard tried to open the Octavo for a bet; he miraculously succeeded in bypassing all safety measures to open the book, whereupon one of the Eight Great Spells leapt from the book and lodged itself into his mind. No wizard could coax it out. Rincewind was expelled from the University since he was unable to learn any other spells, which were afraid to share his head with one of the Eight Spells. Eventually, the Spell returned to the Octavo and Rincewind said all of the Spells to prevent the Discworld's imminent destruction (as described in The Light Fantastic). The book was subsequently swallowed by Rincewind's Luggage, but it was spat out a few days later. Presumably the Octavo has returned to its chamber at the University.
Given its size, it seems unlikely that it is an actual octavo.
Any alumnus from Unseen University is generally free to find an unoccupied study (which are in practically infinite supply), take or possibly invent a title and receive board and lodgings but little or no pay. If he is unlucky, he may then attract students, though this has been stated on at least one occasion to be an unfortunate and largely unwelcome development.
Nevertheless, the Archchancellor is considered an important figure and holds a seat on the Ankh-Morpork council (although this council itself has no power either). He is a sort of magical adviser to the Patrician of Ankh-Morpork as well.
The Archchancellor is elected on the Eve of Small Gods. Well, not exactly elected, because wizards don't have any truck with the undignified business of voting, and it is well known that Archchancellors are selected by the gods (which wizards don't believe in). The double doors to the Great Hall are locked and triple-barred. An incoming Archchancellor has to request entry three times before they will be unlocked, signifying that he is appointed with the consent of wizardry in general. This process seems to satirise the election of the Pope and the Queen's state opening of Parliament at Westminster.
In more recent times, the lifespan of Archchancellors has been seen to be a bit on the short side, as wizardry's natural ambition took its toll. Unseen University has existed for thousands of years, and the average Archancellor remains in office for about eleven months.
Unseen University has had many different kinds of Archchancellor over the years - big ones, small ones, cunning ones, slightly insane ones, extremely insane ones - they've come, they've served (in some cases not long enough for anyone to complete their official portrait) and they've died. The senior wizard in a world of magic has the same prospects of long-term employment as a pogo-stick tester in a minefield.
It should be noted that Mustrum Ridcully, incumbent Archchancellor at the time of the last Discworld novel, Making Money, seems to have had a very successful and above all, injury free career as Archchancellor. He finally put a halt to UU's traditional method of promotion, by assassinating one's superior, simply by being indestructible. This is related to his habit of springing up behind would-be assassins, shouting loudly at them and banging their head repeatedly in the door.
There is also an Archchancellor at Bugarup University on the continent of Fourecks. At last account, this was Bill Rincewind. When the two Archchancellors met, Ridcully was careful to refer to his counterpart without the capital - as 'archchancellor'.
It is noteworthy that in earlier Discworld novels that feature Unseen University staff the wizards usually have names but are also dead by the end of the book, or at least never reappear. With Mustrum Ridcully's appearance in Moving Pictures, the wizard deaths cease, but many aren't named any more, either - they are referred to by their offices instead. There is a slight reference to this in The Last Continent, when the wizards notice that they not only don't know the Librarian's name, but they also don't know the names of one another.