This is probably one of the most contentious issues, the old pink dot problem. It’s very much up to the SG and the troupe.
Some people want their magic to be completely consistent, so pink dot works. Eyes of the cat, Aura of rightful authority, any effects means the mage can’t touch someone with parma.
Others decide Parma is magic. It does not need to be consistent. Parma is about defence. An invisible guy attacking you, the parma spots the risks and blocks it. Eyes of the cat, no reason that is hiding dangerous intentions, the parma does not care. Fast cast a pink dot to protect yourself, the parma is offended at your mockery of magic, and does not protect you.
My problem is more that the pink dot doesn’t seem to be consistent!
If it was, that’d be one thing, but i don’t agree that it is based on the words in the book as it exists (rather than as it exists + some unknown amount of unstated errata from forum posts and mailing lists).
Moonbeam doesn’t need to penetrate because it creates a magical light (lux) that in turn causes mundane illumination (lumen). Lamp Without Flame, which directly magically illuminates an area, can be argued to need to penetrate - potentially making it a powerful tool to allow grogs to jump an enemy maga.
The whole lux/lumen distinction IMO allows for nonpenetrative and penetrative lighting variants. It’s a bit weird to expect players to deeply understand medieval theories of physics etc for spell mechanics, but that’s Ars Magica for you.
I do not believe this to be stated anywhere. It certainly feels off given the logic ars goes eith for how stuff is percieved being “light carries iconic species” but eh.
To be clear aura of rightful authority even under harsh interpretions should not be resisted in most cases.
The Target of Aura is the mind, rather than the body or any other physically oresent attribute. By its Form, the magic is limited to the mind so there’s nothing to resist on contact.
(This is admittedly somewhat inconsistent with imaginem and images, but at least images have a physical component)
Although, of course, one might argue that the mind is no less a part of the physical body than the left hand is part of the right. Certainly, it is not clearly explained why it is or isn’t!
Lux, Lumen and Species are inseparable concepts in the medieval (e.g. mythic european) understanding of sight and colors.
Lux is intrinsic light. Lux is a quality of an object, such as the sun, moon or a flame, that allows it to be seen from any distance.
Lumen is radiated light. Lumen is a quality imparted to a medium, such as air water or glass, by an object with lux.
Species are likenesses. Every object emits species of many kinds, which travel through media. Species require certain qualities of media to be transmitted. In the case of sight species, this quality is lumen.
Thus, a fire has lux, rendering it visible from any distance. As a consequence, it imparts lumen to surrounding air, which allows species to travel, rendering nearby objects visible.
Then, a spell can create a source of lux that does not impart lumen, a source of lux that does impart lumen, sourceless lumen , species that do not require lumen etc.
This is why simple PeIm invisibility effeects (i.e. Veil of Invisibility) still cause the target to cast a shadow. The species they emit are continually destroyed, sure, but they still displace luminous air. A CrIg effect is required to grant the target abnormal lumen, allowing for full transparency.
I think the writers weren’t using the whole lux/lumen phenomona, as can be seen with mien of helios.
MIEN OF HELIOS
CrIg 15
R: Per, D: Diam, T: Ind
This spell causes the caster’s body and personal effects
to shine with the brightness of the sun. Anyone within
10 paces of the caster who looks in the direction of the
caster is temporarily blinded, unless he makes a
Stamina stress roll against an Ease Factor of 9. People
between 10 and 50 paces from the caster suffer a –3
penalty to all attempts to target the caster. The light
created by this spell illuminates a great area and, if
conditions permit, could be seen from several miles
away. Ranulf has noticed that people and creatures
whose Magic Resistance is not penetrated by this spell
are not illuminated by it, and can be easily identified
by their lack of reflected light.
(Base 5, +1 Diameter, +1 exceptionally intense light)
Source: Magi of Hermes, 110
My understanding is under the Lux/Lumen model, the Lux is the property of the caster. The Lumen is external and would thus not need to penetrate. However, that doesn’t seem to be the case.
Thanks, it was effectively paraphrased from memory from Shirleys explanation here. He’s listed as an author/contributor on MoH and Core respectively. Ranulf is attributed to Tyrrell, who certainly understands that the setting assumes aristotlean physics.
Either way, it can be argue that Mien of Helios deliberately (in terms of authorial design) creates magical lux and lumen (i.e. simply ‘light’), rather than specifically creating magical lux and allowing it to propagate into mundane lumen. A variant with or without that bolded section ought to be possible.
YMMV on all of these ‘aristotle implies xyz’. What you don’t understand, your characters may understand even less - a magus may very well have low MT/Philosophiae. If the spell works, it works.
MR is a classic topic around here, and been hotly debated for decades. A couple of things:
Anything to do with Imaginem concerns species (think lux/lumen/photons for visible things, also see p209 and p223 in ArMDE). Species are always inherently natural and never need to penetrate - so you can see illusions. Invisibility works because species are destroyed (but the shadow problem needs to be fixed with complex CrIm).
When it comes to Rego, RAW is pretty clear it just matters if the object hitting you is under the Rego effect still or free of it. Game-wise, if it’s just set in motion - you need to roll Finesse for aiming (i.e. indirect effect, see p223 in ArmDE). But you don’t if you keep it under Rego control (as you can nudge it exactly where you want until it hits), p223 again:
“However, while spells always hit their targets,
indirect effects may not reach the true target;
they must be aimed. If a spell is resisted, as above,
it need not be aimed. If it is not resisted, it must
be aimed.”
Multiple classic spells also exemplify this.
I do find the intricacies and ambiguity around magic effects on individuals and weapons penetrating or not. The default consensus is usually that it needs to penetrate, but I’m more of a fan of the more punishing (and varied) world: I would prefer that yes, the magic damage effect will have to penetrate (such as burning sword), but the sword will still damage fine - as long as it’s not moved by Rego to do so it should be indirect and natural part will hurt. One can start arguing the heat is natural as well (and similar situations with other types of magic), which will require magi to defend magic enhanced weapons with the relevant wards and defensive magic rather than just catch-all not care when Parma is good. I’m personally less of a fan of that “safe” life.
It’s an old “problem” in Ars Magica that magic weapons are completely non-scary… (some say a feature, it does lend a certain charm to the setting to have to rely on mundane tools)
This has been my solution for years; the Pink Dot (or flame) does nothing to you, but the sword does. There’s still the invisible assailant problem, but I’ll argue it out if it ever comes up.
For me, the problem is not with the pink dot conceptually, but rather with the choice of a pink dot specifically - that edge of the razor, or hardness of adamantine, or “the fashionable pink blade” should need to penetrate seems fair enough since those effects actually change the thing which strikes the protected target
But blade of the virulent flame (which creates fire around the sword but does not magically alter the sword at all), or “the fashionably pink handle”, or suchlike? In my opinion not only should they not need to penetrate, it is not even a houserule. I believe that the description of magic resistance in the book does not actually make a clear case for the idea that effects targeting a being in one aspect cause unrelated parts of that same being to be resisted.
And beyond that, as discussed previously, virulent flame doesn't even target the sword!