So Homing Instinct (from RoP:M) let's you memorize a number of outdoor places equal to your Intelligence (at least 1), and you have an arcane connection to that place.
Could you use Art of Memory to increase that number?
If not normally, what kind of research breakthrough would it take?
I love the idea of arcane connections being stored in your Memory Palace, if you have both Homing Instinct and Art of Memory, could you create a spell to memorize new places?
Would other Magi (assuming they have a Memory Palace) also need Homing Instinct to learn the spell?
Art of Memory is not supernatural in any way. While it could on its own allow you to memorize outdoor places, it should not increase your tagged Arcane Connections without some form of magic.
I would consider allowing a variation of the Memory Palace enchantments to create an AC of the location it is cast in. That is very much YSMV though.
The Art of Memory did explicitly used to be a Mystery Ability (TMRE pg. 25), and while it can be used without the Gift or experiencing Realm Interaction effects that doesn't necessarily mean that it's entirely mundane. The Fertility Lore ability in Ancient Magic is similarly unrestricted but allows you to convert fertility into a pawn of Creo vis, for example.
@Sardonic_Laughter As for your original question of modifying/creating a Supernatural virtue that allows you to use the Art of Memory in this manner, that's both plausible and like a potential motivation to investigate the Mystery Cults that used it in antiquity. House Criamon may have done this already: magi walking the Path of the Body have a very similar ability that isn't limited in number.
Since this would be represented as a new virtue (albeit one that's essentially a version of Homing Instinct with a greater scope), it should be at least a Major breakthrough.
That said, you might get some immediately useful spells from studying your Homing Instinct using the Integration rules. Integration effects often contain elements of the final breakthrough and are usually usable immediately by other magi.
This part is very much YSMV, but it might be possible to simply create a Creo Mentem spell that violates Homing Instinct's limits on known locations the same way the Memory Palace spells and rituals do for the Art of Memory.
WHAT! A "Mystery Ability" is not one of the five types of Ability. It is a classification that an Ability is associated with a Mystery Cult. There are five Ability Types, detailed in the core book. Fertility Lore expressly is an Arcane Ability. It says so in its title and twice in the body of its description. The Art of Memory on the other hand is an Academic Ability, with the Troupe option to make it a General Ability.
All of the above, plus the Art of Memory and memory palaces is a description of a real memorization technique that was somewhat common in antiquity. It is as mundane as knowing how to read and write is. Meaning, it is entirely mundane, and even something any of us players can learn if we want to.
Mystery abilities are not among the 5 types of abilities listed in Core, but that doesn't mean it isn't a categorization. What we know about them is the following:
Learning Mystery abilities is possible but potentially hazardous without knowledge of the cult's Organization Lore (TMRE pg. 8)
The Art of Memory used to be a Mystery ability before it entered common knowledge
Synthemata Magia is a Supernatural Mystery Ability
I never said that Fertility Lore is a Mystery Ability, I used Fertility Lore as an example of an ability that doesn't require a supernatural virtue or the Gift, but allows some supernatural process (extracting fertility as Creo vis). Another example is Dead Language (Adamic).
@ErikT just because the ability is mundane in the real world doesn't mean it can't have interactions with supernatural processes in Ars Magica, whether or not it requires the Gift. As far as we know artwork and Ptolemaic Coordinates don't form Arcane Connections in the real world, but they do in Ars Magica. Learning the secrets of ancient cults doesn't grant supernatural power in the real world, even if you perform initiation rites. Simply having a real world-equivalent and being learnable by anyone is insufficient to establish that an ability is completely mundane.
It has entered common knowledge and
can be learned by any scholar, although
it remains uncommon and many lack the
Ability, even though there is no formal
barrier to their learning it.
The Ability may be taught or stud-
ied during play as a normal Ability, or
acquired during creation by any char-
acter with access to Academic Abilities
means it is about as mundane as any other Academic Ability.
Calling it a Mystery Ability doesn't imply there is anything supernatural about it, only that it once was unique to some Mystery Cult(s).
That's just the lack of current restrictions on who can learn it, which doesn't necessarily mean that it is wholly mundane. "About as mundane as any other Academic Ability" isn't particularly mundane either. Several of them still deal with the laws of Contagion and Sympathy, which are how Arcane Connections originate in the first place. It definitely doesn't imply that it is so mundane as to be definitely incapable of interacting with or creating Arcane Connections, which was the original claim.
Calling it (formerly) a Mystery Ability means that learning it used to be uncertain and hazardous without the mystical framework of a Cult Lore, and that it is likely that there are already initiations which deal with this topic.
No more uncertain or hazardous than, for example, a (Cult) Lore. Regular ability, but only available to those inside the Cult.
It is about as mystical as Artes Liberales. Sure, it can be used in conjunction with various magical practices, but that is true of a large number of abilities.
Most Arcane Connections are created through completely mundane means.
Right, as mystical as Artes Liberales doesn't mean it should be incapable of generating arcane connections or incapable of being used in conjunction with a supernatural virtue to do so. That's what was being claimed. A special level of mundanity that even other Academic Abilities don't achieve.
Learning Mystery abilities is hazardous when you don't have a Cult Lore. The Cult Lore isn't a Mystery Ability, it's the ability you need to safely learn a Mystery Ability.