My SG mentioned that you can't bind something with a soul as a familiar, I was wondering where it says that. I thought that the only rule was about Might.
He may be mis-remembering from a previous version, he may be right. If it is not cannon, he will change his mind. He has played Ars since 3rd Ed, so somethings get blurry for him.
Does this sound familiar to anyone?
It's a re-statement of the fact that you can't bind humans, I think.
Also please note that Might is not a requirement, merely associateion with the Magic Realm is sufficient.
Binding demons as familiars is possible (e.g. for a magus with the Virtue Spirit Familiar) and demons certainly have souls!
They don't have free will, though. That's probably a major factor.
...could an angel be a familiar?
Can you really not bind a human? For example, Evil Mage is a master of mentem. Evil Mage declares Wizard's War on Unsuspecting Bjornaer. Evil Mage erases Unsuspecting Bjornaer's memory of being a magus and a human. Evil Magus also uses CrMe rituals to create natural fondness for him in Unsuspecting Bjornaer and is careful not to cause it to leave naturally. In animal form, Hermetic magic treats Unsuspecting Bjornaer as any other animal, though an intelligent one. Evil Magus now binds Unsuspecting Bjornaer as a Familiar.
I don't see where this violates any game rules. Maybe I've missed something?
I'd have to double check, but the same type of shenanigans might work with a lycanthrope if it stayed in its state long enough.
I'd imagine the Bjornaer Flaw No Familiar (or whatever it's called) would work against the idea that a Bjornaer could be bound as a familiar, but I'd say the idea works just fine with any human who has his mind impaired to an animal level whether shape-changed or not.
I am going to step on a slippery slope so consider that I am only offering one point of view and not a cannon explanation. </disclaimer off>
Considering that all human have free will as a gift from God, binding a human through eternal submission (which is one way to see binding a familiar, although it is always agreed by both party) could be what prevent the binding to occur.
On the other hand, without stepping in the dark direction of a mage willing to break the will of a human to make him his pet, you could also consider two lovers who don't want to part. One is a mage and try to achieve a form of "Hermetic wedding" by making his/her partner his familiar to grant him/her long life, the opportunity to share thoughts, feelings and some form of magic.
If in the first case (evil binding), I could see Divine force making impossible this kind of servitude (purely through Deus Fiat), the second case becomes more difficult to argue: both are willing, no trick whether magical/mundane or other was used to force one side into the agreement.
I could be that by becoming a familiar, the person becomes a creature of the Realm of magic, thus his/her soul is destroyed or forfeit in the process, which should be beyond normal hermetic means (on the other hand all the rituals granting Immortality do that). Probably that this would require some Breakthrough if you decide that it is possible within your Saga, but it is definitely not cannon.
The definition and properties of the soul - as you find them in A&A p.31 - in 1220 are not generally agreed upon even within the Church, and certainly not all over Mythic Europe, or within the Order of Hermes.
An important discussion of this topic among Aristotelian scholars has not really started in 1220, and will culminate in Thomas Aquinas' analysis.
A maga pondering, whether her intelligent raven familiar has a soul or not, and discussing that subject with him (it?), is quite in paradigm. So is an uneducated priest pontificating about women not having souls.
Medieval Christians in general expect the resurrection in the flesh at the end of times: so a refined definition of the soul is not an urgent problem for them. Some phrasing in RoP:TD on this topic is pretty modern.
For the overall idea around 1200 have a look at this mosaic:
Cheers
Yes, I think you're right.
I'd gone with Bjornaer with the idea of essential nature in mind as I could see that being problematic.
But forget these shenanigans. I remembered the canon statement that allows a human to be bound!!! Normally you need an animal with Might or at least one "with inherent magic." Faerie Magic behaves similarly, in that you don't actually need one with Might. A sufficiently fay person or animal may be bound, even if they are not actually fully a faerie. Yes, it does say "people" may be bound. It doesn't specify how Warped or whatever they need to be, though.
Uh-oh - I've played in a saga with a Faerie-blooded (huldra) curse-thrower Mythic Companion - if a Merinita had managed to make a familiar bond with that character, things could have gotten seriously weird and there would have been a massive potential for inflation of power-level.
Back to the original topic - Page 103 of the 5th edition rulebook says "A familiar is a beast that a magus befriends and then magically bonds with" so I'd go with a familiar has to be a beast unless you specifically have a virtue that says otherwise. Page 104 says "The first step in getting a familiar is finding an animal with inherent magic" - so the standard familiar has to be an animal, and must have inherent magic (not necessarily a might score, any magical power would meet this rule). If you try to bind a familiar that isn't obviously a beast, your SG is fully justified in saying "please explain to me how this falls into the "beast" category".
The Mysteries p66 begins the spirit familiar section with "This Virtue lets the magus ally himself with a ghost or other incorporeal spirit as a spirit familiar, using rules similar to those for binding an animal familiar" - thereby suggesting animal familiar is definitely the default. It later says a magus may only have one familiar, be it animal or spirit. The last sentence on p66 does say "A tiny minority of magi might consider a demon as spirit familiar, but since this immediately afflicts them with an Infernal taint, others are likely to notice this." p67 says some magi claim to have allied themselves with angelic spirits, but later says this isn't dealt with in that book.
technically a person who has become fae has a might score and has either lost their soul or been replaced by a simulacrum. Demons don't have a soul- they are fallen angels, which despite being divine do not have souls either.
That being said there is nothing that suggests that binding a familiar is inherently subjugating them or breaking their free will if they have it. I think this is something where YSMV has a very heavy hand- in one saga a 'hermetic wedding' making a mundane a familiar might be a minor breakthrough, in another allowing a magus to bind someone with a soul might be outright impossible.
I'll admit that I'm not the greatest when it comes to remembering all the details about the Code of Hermes or the Peripheral Code. But when Wizard's War is declared, don't the two parties have to agree to a set of limits or conditions by which they engage in said conflict? If this is the case, why would the Bjornaer agree to conditions allowing a Mentem magus full access to his abilities unless said Bjornaer thought he himself was a master at Mentem?
Again, it's entirely possible that I read things wrong or am interpreting them wrong. I'm not saying that the above condition wouldn't work; I'm merely questioning the terms behind the war to begin with.
[quote="Ghost
I'll admit that I'm not the greatest when it comes to remembering all the details about the Code of Hermes or the Peripheral Code. But when Wizard's War is declared, don't the two parties have to agree to a set of limits or conditions by which they engage in said conflict? If this is the case, why would the Bjornaer agree to conditions allowing a Mentem magus full access to his abilities unless said Bjornaer thought he himself was a master at Mentem?
Again, it's entirely possible that I read things wrong or am interpreting them wrong. I'm not saying that the above condition wouldn't work; I'm merely questioning the terms behind the war to begin with.[/quote]
Sadly, when it comes to wizard's war the only limits in the core Code are that they must be properly declared, and the time limit. Now, seeing as accidentally harming other magi not involved in the wizard's war is illegal, and so is accidentally depriving them of magical power by destroying labs, stealing books or vis, etc. you tend to end up with one covenant declaring war on another covenant just so everyone's covered. When wizard's war is declared, expect everyone to bring their full power to battle unless they're deliberately showing off. In the case of the Bjornaer, if you know you're outclassed then you'd want to hide away for the entire month of the war, or move tribunal. This can and does mean strong magi sometimes bully other magi relentlessly, or run people out of the Tribunal - this is why the 5th edition Tribunal books are littered with failed and ruined covenants that couldn't withstand war or persecution.
[/quote]
If depriving the opponent of magical power is illegal, wouldn't wiping their memories and knowledge of magic fall into that category? Probably more of an ethical question to be dealt with on a case-by-case basis, but no harm in asking the theoretical implications, is there? 
The terminology in RoP:F disagrees with you. RoP:F uses "fay" to mean highly faerie but not necessarily and actual faerie (with Might). See my quote from RoP:F above where it notes the exceptions to the Might Score.
But that's depriving other people, not the target of the WW. Mind wiping the target of the WW is fine.
Interesting. Makes me want to try creating and playing a Mentem specialist now.
yes you have missed something
as said in ARM page 103 right
so the familiar is not the SLAVE of the magus but is best friend. You don't force the animal (ou spirit or else) to be your familiar and the familiar have is own though and action. For me it's totaly opposite to the notion of a master in mentem (or animal) magic who force you to be his familiar.
For the question of this thread, since the familiar link is a agree to agree processus I don't see why a people with soul can't be a familiar.
P104, "... it must trust you freely, under no coercion, magical or mundane"
In our saga we have a group of sentient rats, which were created by a bonisagus, but the experiment got a little away from him. They are no-longer mundane rats, each generation becomes taller, stronger and more "human". They talk, they craft, they have a society based on old Rome. Some of them have Might scores, some don't.
Our covenant priest is trying to convert them to Christianity, and there are several demons set up as false gods.
Hence the question, can any of them be bound as familiars?