Why do Magi not just take mundanes, teach them Magic theory and use them in the lab. Ideally they could use Muslims because slaves have no rights (unlike apprentices who run away as soon as they know what they are doing?)
Your lab assistant needs to know Magic Theory and have The Gift.
If the character doesn't have The Gift, he can only copy texts with Magic Theory, Latin, and Profession (Scribe) skills.
"mundane" was the wrong word - I meant people who do not have their Arts opened and are ideally to old to be apprenticed (15 or so).
I suppose an old (adult) Gifted character could make an ideal lab assistant, as you say. I think they'd be rather rare, however. Magi are constantly on the look-out for Gifted individuals, and those they haven't reached probably end up developing in hedge traditions not amicable to such close relations with the Order. The more powerful hedge traditions will always be on the verge of being forced to join the Order, for example.
It really depends on how rare the Gift is. If in your saga the Gift is relatively common, then this might be possible.
If, however, the Gift is rare even adults who are Gifted will be made apprentices. Being old is no impediment to having your Gift opened. It is only if the apprenctice already has Supernatural Abilities that there are some problems.
There's no automatic age by which you're no longer eligible for apprenticeship.
PS. If you're hoarding a Gifted person as your personal assistant, and he or she's suitable to become an apprentice, you had better be very careful about who finds out. Don't let the Gifted slave read any Order of Hermes Lore books. It could get expensive. I don't think you would get Marched though . . . maybe, but I doubt it.
You wouldn't get marched. You would be either required to give them training or tribunal would take them and give them to someone that would give them training.
There is some examples related to that mentioned in the apprentice section of the main book.
It is one of the changes from 3rd/4th to 5th that help in the lab had to be gifted.
I'm not sure that there is much cause for trouble if Gifted people, who are not magi, learn Order of Hermes Lore. It's just an Organisation Lore. Heaps of supernatural critters, and faeries, and so forth, that interact with Order are likely to have a Score in this Ability. I don't think it is a big secret.
The real problem is if your Gifted slaves learn Parma Magica, without becoming members of the order. That would get you marched.
Maybe some Mystery Cults would also be upset if books about their Mystery Lore were read by non-magi (or indeed any non-member of the Cult).
My point was that should the "slave" learn about his rights, especially the one season of training a year for 15 years, he may go running to a Quaesitor himself.
Ah, good point.
You are right that could get you into some minor trouble.
If you didn't formally make them your apprentice you won't be in trouble for not providing training --- but, of course, you will then be vulnerable to someone else claiming the slave as an apprentice. Either way if the slave learns what the rights of an apprentice are supposed to be then there could be some problems.
Really depends on how uptight your local Quaesitors and Tribunal want to be about the "I will train apprentices" stipulation of the Code. Granted, its usually interpreted to make the decision to have an apprentice at all optional. But you can bet you would be in a heap of trouble if you took a potential apprentice and part trained him or her to be a lab assistant, but not a full apprentice.
Its unlikely you'd get Marched, though it could be argued to be a high crime. But you can bet you'll get slapped around if you aren't everyone's favorite wizard.
Ah, but only if you have actually opened his Arts. If you haven't, then he is not your apprentice and you don't owe him anything. Of course, in such a case, any other magus can just waltz in and pick him up, rather than only a Bonisagus.
So if he were to learn of apprentices' rights, the worst he could do would be to request you, or more likely another magus, to formally take him up as an apprentice.
Now, as for the Gift being necessary in a lab assistant, let's reopen the old "Failed Apprentice" can of worms...
I thought HoH:MC made it clear that Veriditus had non-gifted lab assistants, and Covenants also pointed out that servants/slaves could be in the lab.
You can have non gifted assitants in the lab but they don't give you the intellegence + magic theory bonus that you'd get from a gifted assitant (or your own familiar). Covenants has virtues to reflect these sorts of asistants (there's one for servents and one for guards IIRC there may be others as well)
I disagree. I think in most sagas potential apprentices are a rare commodity, and not turning them into magi and perpetuating the Order would be frowned upon by many. In any event, a Flambeau spoiling for a fight doesn't need a iron-clad reason to March someone in the first place.
Say you went around killing unapprenticed, Gifted children wherever you found them and the magi in your Tribunal found out. Is your position that they didn't have their Arts Opened, so it's no problem? I think misuse of magical resources (potential apprentices) could get you in trouble if you are politically weak or have enemies in the Order looking for a reason to mess with you.
Oh, I'm not arguing whether it would or not, nor that the politics of it wouldn't do you in in the long term, but strictly speaking, it's not a violation of the code. They are not your apprentices, you don't owe them anything. If other magi disagree, it's up to them to come up and claim your "lab assistant" as an apprentice. Theoretically, you'd have grounds to claim they reduced your magical power in doing so, but I don't think it would go too well if you did. (Oh, yes, please, come to us and complain, we're just waiting for that. 
)
To declare a Wizard's War? No, they don't need a reason.
If they are no-one's apprentice, then yes, it's no problem. The morals may be wrong, but again, it's not a violation of the Code. Gifted people who aren't Hermetic magi or apprentices are in no way protected by the code, be they Gifted children or full-fledged hedge wizards.
And if they are your apprentices, they are yours to dispose of if you deem it necessary. Callous, I know, but that's the way things stand.
That goes without a question. They could use it to turn more magi against you, so that if/when you do something that's actionable, they can come down on you. Interfering with mundanes and endangering the (future of the) Order come to mind.
The example of the apprentice-snatching-and-killing Bonisagus who got seven simultaneous Wizard's Wars declared on him is an edifying example. It isn't, however, a formal Tribunal-decided Wizard's March.
I don't really know what the point of your post was, Fruny. I never said it was a violation of the Code. I said it would be frowned upon by other magi. There are ways to punish what's permissible under a strict interpretation of the Code, but still unpopular or in bad taste. And just because it's not a topic in the Hermetic Oath, doesn't mean that magi are going to allow someone to get away with something that is underhanded or weakens the Order.
As ArM5 p. 107 states:
So you can do whatever you want in your saga, but enslaving a Gifted person isn't normally allowed by the Tribunal. If a player in my saga tried it, I'd make his character's life a living hell.
In a saga populated by rational NPCs, you would get nuked. Just because it's legal doesn't mean the rest of the Tribunal is going to allow you to get away with it. If a Tribunal normally intervenes to protect an enslaved Gifted person, you really think they're going to sit on their hands while some psychopath goes around slaughtering their potential apprentices?
I guess that what bothers me most is that we are talking about people who (variously) let a Flambeau go unchastised because he didn't leave any witnesses to accuse the Order, accepts that a magus kill his apprentices (leading those magi whose apprentices got bonisnatched to declare Wizard's War), allow direct raiding of one's resources and who will merely take a Gifted lab-slave away.
There is a distinct difference between what is legal and what is accepted, what any one magus or group (house, covenant, tribunal or clique) feels is "right".
Does enslaving one gifted person "deprive" others of their magical power? Meh - hard point to push, but no more than taking unclaimed vis for your own deprives others. Does killing them has a hobby do so? Most would say "yes". Is a gifted child of greater value than a gifted adult? All things equal, yes, if only because at some point apprenticeship drives the apprentice into adulthood and aging before they can make their own longevity formulae - and adults tend to be less malleable than children.
(In earlier editions there was a cut-off age, around 20 iirc - now, not so much, but it could still be RP'd even if not a hard RAW.)
These are not absolutes, but matters of degree, of personable preference, and subject to infinite variables. Both positions are right or wrong, depending on those variables - I can see both occurring acceptably, and both bothering me if I was in the game, depending on those details.
The one thing I think can be agreed upon is the rarity of (known) potential apprentices, that for every one found there is probably a magus willing to take them under their tutelage. Unless the gifted lab assistant was a failed apprentice (a true find!), or otherwise obviously flawed beyond desirability, it would indeed be wise not to advertise the fact, nor to give the servant too long a leash. If another mage were to claim the servant as their apprentice, it would "diminish your magical power", but it is also their right to apprentice them - unless your mage relishes such political conflicts and a good old fashioned coin toss in Tribunal, it's something to be avoided.