[OB] Soulcaster Engineering Principles

[Vortaan]

Hello everyone. In this topic, I'd like to talk about the engineering principles behind Soulcasters, and to a lesser extent Regrowth fabrials and Honorblades. With Oathbringer, we finally have a PoV of someone using an actual Soulcaster, plus some interesting information in the Ars Arcanum and some further knowledge on the Honorblades. So with all that in mind, let's get to it.

First, I'd like to talk about the actual composition of the Soulcasters. From Way of Kings, here is our first actual description of a Soulcaster.

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On her freehand was a distinctive piece of jewelry: two rings and a bracelet connected by several chains, holding a triangular group of gemstones across the back of the hand. A Soulcaster— the word was used for both the people who performed the process and the fabrial that made it possible.

Sanderson, Brandon (2010-08-31). The Way of Kings (The Stormlight Archive, Book 1) (p. 84). Tom Doherty Associates. Kindle Edition. 

Soulcasting fabrials have some limitations that actual Knights Radiants Soulcasting don't seem to have. Not all Soulcasters are able to Soulcast every essence, as stated by Shallan here.

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It was true; Jasnah really did have a functioning Soulcaster. And a powerful one too. Nine out of ten Soulcasters were capable of a few limited transformations: creating water or grain from stone; forming bland, single-roomed rock buildings out of air or cloth. A greater one, like Jasnah’s, could effectuate any transformation.

Sanderson, Brandon (2010-08-31). The Way of Kings (The Stormlight Archive, Book 1) (p. 91). Tom Doherty Associates. Kindle Edition. 

In addition, Soulcasters are only able to Soulcast things into an essence that has a corresponding gemstone on the fabrial. Emeralds for food, smokestones for smoke, garnets for blood, etc. This is directly different from how Radiant Soulcasting seems to function, as Jasnah uses multiple essences in the battle for Thaylen city without any particular types of gemstones being noted as being drained.

So what are Soulcasting fabrials doing? It appears they are giving limited access to the Transformation surge. It appears that, unlike Shardblades, they have no inherent primary user. It also appears that the process to Soulcast is something people get better with as time passes, but it has devastating side effects on those who use them. We have seen Soulcasters with granite casts to their skin, with vines growing from their eyes, and even those who are turning into smoke. All of these incidences have led me to the follow conclusion

Conclusion: Soulcasting Fabrials create a weak approximation of a Nahel bond

The only ways we have seen on Roshar to access the Surges are various bonds with the sentient Investiture that Rosharans call spren, by being directly Invested by a Shard (Fused), or by holding an Honorblade. We can cross being directly Invested off the list of potential ways Soulcasting fabrials allow access, as the people using them still require contact with the Soulcaster to use it. Likewise I believe we can cross off a bond with a spren, as while the Soulcasting savant feels a presence when she Soulcasts, she does not see anything, and she is far enough into Shadesmar that in my opinion spren should not be able to hide from her. That leaves the Honorblades. The Honorblades grant a link to two Surges to whomever touches them. We see this with Bridge 4 using Jezrien's Honorblade. In addition we see another similarity between the Honorblades and the Soulcasters: the color of the metal.

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“Oh, Stormfather,” Jushu said, pulling it out. The device consisted of several chains of silvery metal connecting three large gemstones, one of which was cracked, its glow lost. “Is this what I think it is?”

“A Soulcaster,” Shallan said.

Sanderson, Brandon (2014-03-04). Words of Radiance (The Stormlight Archive, Book 2) (p. 872). Tom Doherty Associates. Kindle Edition. 

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This Blade didn’t have one. Dalinar hesitantly reached out and rested his fingers on its silvery length. It was warm to the touch, like something alive.

“It doesn’t scream when I touch it,” he noted.

The knights, the Stormfather said in his head, broke their oaths. They abandoned everything they’d sworn, and in so doing killed their spren. Other Blades are the corpses of those spren, which is why they scream at your touch. This weapon, instead, was made directly from Honor’s soul, then given to the Heralds. It is also the mark of an oath, but a different type— and does not have the mind to scream on its own.

Sanderson, Brandon (2017-11-14). Oathbringer: Book Three of the Stormlight Archive (p. 166). Tom Doherty Associates. Kindle Edition. 

I will concede that this is a tenuous connection, however: Honorblades appear to be physical manifestations of Honor's power, much like lerasium, atium, or ettmetal. The color of the metal could be an indication of a shared origin. Both seem to require large amounts of Stormlight to function. Both create a weak bond on touch, and require some time to learn how to use. Honorblades can be dismissed, while Soulcasters cannot, but that could be a property of Soulcasters not being intended as weapons. The link between the two is reinforced in the Ars Arcanum, where Khriss seems to think that Soulcasting fabrials, medallions on Scadrial, and Honorblades all work by similar principles.

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Soulcasters, the devices, were created to imitate the abilities of the Surge of Soulcasting (or Transformation). This is yet another mechanical imitation of something once available only to a select few within the bounds of an Invested Art. The Honorblades on Roshar, indeed, may be the very first example of this— from thousands of years ago. I believe this has relevance to the discoveries being made on Scadrial, and the commoditization of Allomancy and Feruchemy.

Sanderson, Brandon (2017-11-14). Oathbringer: Book Three of the Stormlight Archive (p. 1242). Tom Doherty Associates. Kindle Edition. 

What I believe occurs in each case is that the possession of a medallion, Soulcaster, or Honorblade temporarily overwrites the person who is using it's Spiritweb to make them a temporary Metalborn or Surgebinder. In the case of medallions, we are shown that knowledge of what the medallion can do is necessary to unlock it's power. We see this with the weight medallions used in the airships and by the coin Wax acquired from Hoid. Soulcasters do not have this problem as most of Roshar knows what they are on sight, and Honorblades have been sequestered in Shinovar and seem to have been used for training Surgebinders for unknown purpose. Clearly the Shin know what the Honorblades do, and so the Intent is not a problem there either. 

This temporary overwrite causes problems for the recipients down the road, however, I think. In the case of Soulcasters and Honorblades, they are required to draw dangerous amounts of Investiture into their Spiritwebs, probably exacerbating any cracks already there and probably giving them an increased likelihood of savantism. Medallions likely don't have this problem as much because of the relatively limited amounts of Investiture in their use.

Anyway, that's my current theory. What do you guys think?

[Calderis]

Agree on all counts. 

You pretty much wrote out my opinion for me, in greater detail than I had thought of it. 

Thank you. 

[digitalbusker]

The only part of this I'd quibble with off the top of my head is the assertion that Radiant Soulcasting can fuel any transformation from any gem. In The Way of Kings, when Jasnah is Soulcasting she drains the appropriate gems. And when Shallan accidentally turns the goblet to blood she's holding a garnet.

Counterpoint: if Jasnah is able to fuel any transformation with any gem, then of course she's going to choose to use the expected gem types so as not to draw suspicion. But the fact that Shallan got blood from a garnet indicates there's some association, even if it only comes into play when the Radiant doesn't specify.

So it could be that Jasnah can do any transformation with any kind of gem, but it does appear that the gems are still used, and she's not just drawing in the Stormlight and using it directly. (At least in book 1.) Otherwise we wouldn't expect gems to break. We never see any other surgebinders break gems by simply drawing light out of them, but Jasnah breaks I think two gems in tWoK (one in the palace and one in Crime Alley).

Maybe it's possible to do it either way (fuel a transformation directly with your own Stormlight or pay for it out of gems you have on you), and the gem only matters in the second case (if at all), and Jasnah either didn't know that or didn't want to risk glowing. Maybe during the battle at the end of Oathbringer Jasnah is fueling all her transformations with light she's already inhaled and so didn't have to worry about having gems of specific types. Or maybe she was carrying around a ton of different polestones and we just didn't get a mention of it because when you're in the middle of a Brandon Avalanche you don't have time for detailed inventory management. We don't get, even in her own PoV, a description of the negotiations with the things she's changing, but from her discussion with Shallan we know it's happening.

On the broader point of how the lesser Soulcasters work, I think you're probably pretty close. I suspect there's a spren involved in each transformation. Whether it's the same spren each time or the fabrial is facilitating a deal with whatever spren is handy, I'm not sure.

Edited January 1, 2018 by digitalbusker
Negations->negotiations

[Vortaan]

32 minutes ago, digitalbusker said:

The only part of this I'd quibble with off the top of my head is the assertion that Radiant Soulcasting can fuel any transformation from any gem. In The Way of Kings, when Jasnah is Soulcasting she drains the appropriate gems. And when Shallan accidentally turns the goblet to blood she's holding a garnet.

Counterpoint: if Jasnah is able to fuel any transformation with any gem, then of course she's going to choose to use the expected gem types so as not to draw suspicion. But the fact that Shallan got blood from a garnet indicates there's some association, even if it only comes into play when the Radiant doesn't specify.

So it could be that Jasnah can do any transformation with any kind of gem, but it does appear that the gems are still used, and she's not just drawing in the Stormlight and using it directly. (At least in book 1.) Otherwise we wouldn't expect gems to break. We never see any other surgebinders break gems by simply drawing light out of them, but Jasnah breaks I think two gems in tWoK (one in the palace and one in Crime Alley).

Maybe it's possible to do it either way (fuel a transformation directly with your own Stormlight or pay for it out of gems you have on you), and the gem only matters in the second case (if at all), and Jasnah either didn't know that or didn't want to risk glowing. Maybe during the battle at the end of Oathbringer Jasnah is fueling all her transformations with light she's already inhaled and so didn't have to worry about having gems of specific types. Or maybe she was carrying around a ton of different polestones and we just didn't get a mention of it because when you're in the middle of a Brandon Avalanche you don't have time for detailed inventory management. We don't get, even in her own PoV, a description of the negotiations with the things she's changing, but from her discussion with Shallan we know it's happening.

On the broader point of how the lesser Soulcasters work, I think you're probably pretty close. I suspect there's a spren involved in each transformation. Whether it's the same spren each time or the fabrial is facilitating a deal with whatever spren is handy, I'm not sure.

I thought about this and the closest to an answer I came up with is that Jasnah was playing the part of a person with a Soulcaster. There are probably two different ways Radiants can Soulcast. The first way is to draw the Stormlight into themselves and then Soulcast, which removes the Essence limitations. The second way is to directly offer the Stormlight from the gemstones, in which case the gemstones act as a filter and limit their options. I suspect Jasnah was extremely careful to only use this second form of Soulcasting when anyone was around.

[Calderis]

@digitalbusker @Vortaan

The way that I understand it, Radiants can do both. 

If the Radiant does what Jasnah did all through tWoK, and gives the stormlight directly from the gem to the bead, then they would be limited by the essence of the gem type. We never once see Jasnah glow in tWoK. 

On the other hand, if they infuse they can then use the surge directly and power any transformation they want. 

The fact that Radiants aren't bound by gem type is established in both the AU Roshar Essay by Khriss, and these

https://wob.coppermind.net/events/181/#e3824

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ebilutionist

As for soulcasting - now that is... interesting. So are Surgebinding fabrials more rigid in general? And what of an Honorblade when a non-Herald uses it?

Brandon Sanderson

A soulcaster is built to do a certain thing, and can do that certain thing well, but without as much flexibility. It is the difference between having a computer output a picture of a circle--following some inputs such as size and some changes to shape--and having an artist who can draw what you want.

https://wob.coppermind.net/events/128/#e3243

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Darkness (paraphrased)

Right, so… is it easier for a Soulcaster to turn rock into smoke with a smokestone as opposed to a ruby?

Brandon Sanderson (paraphrased)

So… Soulcasting… is gonna really depend on whether you're using a soulcaster.

Darkness (paraphrased)

First is for a Soulcaster, second is for a Surgebinder.

Brandon Sanderson (paraphrased)

A Surgebinder is far less constrained than someone using a device accessing surges, right? A Knight Radiant is far less constrained than somebody using a mechanical means of accessing magic, and I would include Honorblades as a mechanical means of accessing a surge.

 

[RShara]

One slight modification (yay pedantry).  The color or type of gem doesn't actually matter.  But because Rosharans have associated each type of gem with an Essence, it matters for them.  This doesn't actually affect your theory, I'm just being thorough.

https://wob.coppermind.net/events/128-supanova-2017-sydney/#e3243

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Darkness (paraphrased)

Further on in that… do different gemstones hold a different flavor, or different "frequency" of Stormlight?

Brandon Sanderson (paraphrased)

Umm…. Nnnnnnnnooooooo… But kind of? Here's the thing: So with the gemstones on Roshar… scientifically some of these gemstones are just really close to one another. Like chemical formula and whatever. But, their cognitive selves and their spiritual selves are gonna be very different because of human perception, right? (sure) And so, the answer is both a no and a yes because of that. So people's perception has sort of changed how the magic works, to an extent… but it's the same amount of investiture, just with slightly different flavorings.

Darkness (paraphrased)

Right, so… is it easier for a Soulcaster to turn rock into smoke with a smokestone as opposed to a ruby?

Brandon Sanderson (paraphrased)

So… Soulcasting… is gonna really depend on whether you're using a soulcaster.

Darkness (paraphrased)

First is for a Soulcaster, second is for a Surgebinder.

Brandon Sanderson (paraphrased)

A Surgebinder is far less constrained than someone using a device accessing surges, right? A Knight Radiant is far less constrained than somebody using a mechanical means of accessing magic, and I would include Honorblades as a mechanical means of accessing a surge.

Darkness (paraphrased)

Cool! So with the whole Jasnah scene, she inhales Stormlight, for using Soulcasting. So how is it the Soulcaster appears to glow more fiercely instead of growing dimmer in that scene?

Brandon Sanderson (paraphrased)

Um… heh heh heh… So… this is perception on Shallan's part, watching and kind of resonating with the Soulcasting, and some weird things are happening that she sees, and not necessarily anyone else is seeing.

Darkness (paraphrased)

I love that! Alright… Also, did Taravangian recognize that Jasnah was not Soulcasting traditionally? Like was it the hand sinking into the rock that gave it away?

Brandon Sanderson (paraphrased)

Taravangian knew and already suspected.

 

[+Hoiditthroughthegrapevine]

@Vortaan amazing post! The linkage between the honorblades, soulcasters and Scadrian medallions is really well thought out and I think you are definitely onto something there. I like the analysis of the properties of the metals and the necessity for physical contact. The bit about the honorblades feeling warm to the touch was a great bit of detail too.

I think I disagree with your conclusion though:

12 hours ago, Vortaan said:

Conclusion: Soulcasting Fabrials create a weak approximation of a Nahel bond

We know that the Cosmere is composed of three primary forms of matter/energy, Physical Matter, Cognitive Energy, and Spiritual Energy/Investiture. We also know that like Matter and Energy in our Universe, these three primary forms are convertible between these different states. Investiture can become cognitive energy (spren, seons, the Returned), Investiture can become Physical matter (honorblades, planets, physical bodies of inhabitants of planets, soulcasters, Larkin growing from consumed Stormlight/Voidlight). Cognitive energy can become physical matter (shardblades, shardplate). Physical matter can be converted into new types of physical matter with the addition of Cognitive Energy and Spiritual Energy (bonded spren + stormlight). Physical matter can be converted into Investiture (Lift's ability to metabolize food into stormlight, though this seems like an extreme special case, maybe because she has a piece of Investiture that is able to effect this transformation).

So an analogy, that at least works for me, is that Spiritual Energy or Investiture is the Highest Potential energy state of Energy/Matter in the Cosmere. The transition to another lower state of energy/matter releases an enormous amount of Kinetic energy that can be harnessed to do productive work. Cognitive energy is the next step down from Spiritual energy, and therefore has the inherent ability to convert to Kinetic energy as well though with far less energy released. In the physical state of matter there is no more latent potential energy, for matter to transition in this 0 potential energy state to something else it requires the addition of external energy.

But, just like in our world, free energy or Kinetic energy would dissipate into radiant heat unless there was a channel or pre-defined means for it use to do effective work. Another analogy would be the purposeless stored energy of a battery, if not given the proper channels to do effective work, say the positive and the negative terminals were connected without any intervening circuitry, the battery would just generate heat. But given the proper connective bridge, this source of power could do anything conceivable. This is how I think Investiture/Spiritual energy works.

In the framework of this analogy, a Knight Radiant using the Nahel bond to soulcast, the bonded spren would be the channel (or circuitry, the translation of cognitive intent into a form that it can do meaningful work in the physical realm), the Investiture or stormlight would be the stored chemical potential energy of the battery, and the physical realm manifestation of work would be the use of Energy directed along a cognitive channel to change one form of matter into another form of matter.

Holy crap that's a long prelude to get to the point of contention, but I do think this is important. So to continue the analogy, a soulcaster is like a partial circuit, it would have to be because anyone can use it. The portion of the circuit that is incomplete has to be created each time Power is drawn through the system. It is designed to do a specific thing, turn any form of matter into 1 or many different composite forms of matter. The way I see this functioning is that the missing portion of the circuitry or channel that is needed for the High Potential energy load of the Investiture/Spiritual Energy (normally provided by a Nahel Bonded spren which is itself cognitive energy) has to come from somewhere. I think that the physical matter of the soulcaster (using the power of the Spiritual energy (stormlight in the gemstone)) is converted into this necessary extra additional bit of circuitry (or to speak more generally into the Cognitive Energy bridge necessary to direct the Kinetic energy of the Spiritual Energy to do productive work). This means that the soulcaster is converting the physical matter of their body into Cognitive energy (using the external energy of stormlight to catalyse this transformation) to direct the Spiritual energy of stormlight to effect a transformation of matter into another form of matter. So essentially, what I think is happening is that the soulcaster is using the stormlight to transmute the physical substance of their body into Cognitive energy, and then using that cognitive energy as a bridge/connnection/pathway to direct more of the stormlight's kinetic energy to turn one form of matter into a different form of matter.

The fact that soulcasters begin to turn into the Cognitive substance that they are transmuting things into seems like a mild confirmation of this theory. Their physical aspect is being consumed to create a cognitive aspect in line with the transformation they wish to make.

This quote from the Kaza Interlude in OB I think gives additional credence to this theory:

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"It is easier to Soulcast an entire object, but I am no ordinary Soulcaster. I have begun to see the dark sky and the second sun, the creatures that lurk, hidden, around the cities of men."

 

Another interesting bit from this interlude is that it seems like soulcasting is not as easy as Kasbal made it seem in WoR. There is this bit, also from the Kaza interlude that seems to imply that there is something more arcane about the use of a soulcaster:

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Even as she righted herself, she felt in her pouch for the comforting touch of her Soulcaster. Hers, no matter what the rulers of Liafor claimed. Had they spent their youths caressing it (Touch seems significant), learning its secrets?

The parenthetical aside is my own addition, but I think @Vortaan you are onto something with the fact that the soulcaster has to be touching the soulcaster.

Anyways, I have spent the better portion of the day working on this, I have to finish at some point, and I think this is it. Your post was amazing, I think you are right in the main, but I disagree with your analysis about how the soulcaster is working.

Edited January 2, 2018 by hoiditthroughthegrapevine

[RShara]

I wonder if the silvery soulcaster metal could be Cultivation's god-metal?  We know that god metal isn't necessarily indestructible, and soulcasters (transformation) seem to be something Cultivation would be into--transforming one un-useful material into a useful material. 

If it is Cultivation's god-metal, it makes sense to me that it is attracting some sort of specific spren to help the transformation.  Or, at a stretch, possibly even Cultivation herself.

[Furry-And-Lovable-Grover]

On 1/1/2018 at 0:39 PM, digitalbusker said:

The only part of this I'd quibble with off the top of my head is the assertion that Radiant Soulcasting can fuel any transformation from any gem. In The Way of Kings, when Jasnah is Soulcasting she drains the appropriate gems. And when Shallan accidentally turns the goblet to blood she's holding a garnet.

Counterpoint: if Jasnah is able to fuel any transformation with any gem, then of course she's going to choose to use the expected gem types so as not to draw suspicion. But the fact that Shallan got blood from a garnet indicates there's some association, even if it only comes into play when the Radiant doesn't specify.

So it could be that Jasnah can do any transformation with any kind of gem, but it does appear that the gems are still used, and she's not just drawing in the Stormlight and using it directly. (At least in book 1.) Otherwise we wouldn't expect gems to break. We never see any other surgebinders break gems by simply drawing light out of them, but Jasnah breaks I think two gems in tWoK (one in the palace and one in Crime Alley).

Maybe it's possible to do it either way (fuel a transformation directly with your own Stormlight or pay for it out of gems you have on you), and the gem only matters in the second case (if at all), and Jasnah either didn't know that or didn't want to risk glowing. Maybe during the battle at the end of Oathbringer Jasnah is fueling all her transformations with light she's already inhaled and so didn't have to worry about having gems of specific types. Or maybe she was carrying around a ton of different polestones and we just didn't get a mention of it because when you're in the middle of a Brandon Avalanche you don't have time for detailed inventory management. We don't get, even in her own PoV, a description of the negotiations with the things she's changing, but from her discussion with Shallan we know it's happening.

On the broader point of how the lesser Soulcasters work, I think you're probably pretty close. I suspect there's a spren involved in each transformation. Whether it's the same spren each time or the fabrial is facilitating a deal with whatever spren is handy, I'm not sure.

I think another scene to consider in this is the scene where Shallan is poisoned in tWoK. Jasnah specifically calls for a garnet to soulcast blood because she is terrible at Transforming organics. Given the WoB @RShara pointed out, on whether a given gem is necessary, it does seem like certain gems aid specific Transformations because of Cognitive association/Connection. I tend to feel like that does support an approximation of a nahel bond, given that a Soulcaster Fabrial would be dependent on a particular type of spren needing to be present to power it, as a Fabrial. 

 

Looking further into the change in the people who use Soulcasters, It seems to me that the change happens to them perhaps out of needing to touch the spirit web of the target with their own? It would make sense if some of the Transformation transferred across a link like that.

[Vortaan]

Ok so: I am not in a frame of mind right now where I can get into too much stuff, so @hoiditthroughthegrapevine I will address your post soon when I have more time to digest it, but for the other stuff:

4 hours ago, RShara said:

I wonder if the silvery soulcaster metal could be Cultivation's god-metal?  We know that god metal isn't necessarily indestructible, and soulcasters (transformation) seem to be something Cultivation would be into--transforming one un-useful material into a useful material. 

If it is Cultivation's god-metal, it makes sense to me that it is attracting some sort of specific spren to help the transformation.  Or, at a stretch, possibly even Cultivation herself.

I would buy it being tied more to Cultivation than Honor. I'm not sure about it attracting a specific spren so much as... I don't know. Spren that embody change? That's a concept, it has to to have a spren, although I'm not sure what kind of spren it would be. I certainly don't think they are bound either to the person or to the fabrial, just that maybe when they Soulcast it sends out a "please help me, gotta make the donuts" beacon?

3 hours ago, Jhardin said:

I think another scene to consider in this is the scene where Shallan is poisoned in tWoK. Jasnah specifically calls for a garnet to soulcast blood because she is terrible at Transforming organics. Given the WoB @RShara pointed out, on whether a given gem is necessary, it does seem like certain gems aid specific Transformations because of Cognitive association/Connection. I tend to feel like that does support an approximation of a nahel bond, given that a Soulcaster Fabrial would be dependent on a particular type of spren needing to be present to power it, as a Fabrial. 

There's a couple things happening in that scene. One, Jasnah is limited by needing to not reveal her secret that she's able to Soulcast without a fabrial, so she needs the garnet to justify Soulcasting Shallan's blood. Two, Blood is one of the essences, so actually doing it shouldn't fall into Jasnah's "really bad at organics" thing. The ten Essences are the easiest things to Soulcast, further you get from them, more problems you have. Three... I have no idea what the idea is with gems beyond some kind of mass Cognitive effect similar to what causes the Returned to look like they do. Everyone assumes a god should look godly, so they do. Everyone assumes garnets are a focus for Blood, so they are.

[11thorderknight]

With regard to Jasnah's Soulcasting in tWoK - remember, the fact that she isn't using a device is part of the Big Reveal of the book. Ergo, BS didn't have a choice; he had to write the Soulcasting scenes as conforming to the general expectation of mechanical Soulcasting, strictly from a meta perspective. He sort of had to work backwards here. The In-World explanation that makes the most sense, to me, is the fact that Jasnah is trying very hard to keep a secret. Shallan Soulcasting blood happens too early in the book to allow the secret to be given away; hence, it doesn't really matter what handwaving we have to do in order to justify it - it simply had to be written that way. My explanation would be that Shallan knows that garnet = blood, and subconsciously knew the "flavor" of Stormlight she inhaled; therefore, she gets blood. Also makes for a great segue to the suicide attempt. Alternatively, it could be that the associated Essence is the default state for Radiant Soulcasting, and Shallan doesn't know how do change the default. Might require more Stormlight to do so, or might just require a mental trick. Ether way, Shallan can't do it yet at that point. 

Regarding Jasnah calling for a garnet - if you think about it, the jig's already up at that point. Jasnah's not going to let Shallan die, so she makes an attempt to stick to the story, but in reality, a sphere could never fuel a mechanical Soulcaster - we're shown many times that the real devices require a large stone of a specific cut, installed into the device. She might manage to fool a poisoned Shallan (until she's feeling better) or the common people in the room, but to the eyes of a knowledgeable observer, the cover's blown at that point. 

With regard to cracking gemstones - mechanical Soulcasters do this, so Jasnah feels the need to periodically do so as well - publicly. Maybe she's learned to "suck" on a stone so hard that it snaps, or whatever. Anyway, she "knows", prior to Soulcasting the boulder, that she's "very likely" going to lose a valuable stone - why not take 2 seconds to swap out one or both of the other gems for another smokestone? It's implausible to believe that one of the three wealthiest women in the wealthiest kingdom on the planet wouldn't have a spare or two with her. And yet, the gemstone that's cracked from being over-drained still somehow has just enough juice to disappear the entire boulder? A bit on the coincidental side. Ditto for the street thugs; she's got enough Light in the smokestone for two of them, but just barely? 

And finally - what's the In-World reason that Jasnah "discovers" the "Soulcaster"? She obviously doesn't need the money, or the assassination attempts, and having been digging into records of the Recreance and the Desolations she must have come across hints of the various secret societies. The meta reason is obviously that Shallan needs to have a reason to seek her out, but the In-World reason, imho, is the reverse: Jasnah wants other potential Radiants to seek her out also. It's like a dog whistle to anyone else who has discovered Surgebinding abilities. Unfortunately, it's a dog whistle the Ghostbloods can hear as well.

Edited January 3, 2018 by 11thorderknight

[Calderis]

7 hours ago, 11thorderknight said:

Regarding Jasnah calling for a garnet - if you think about it, the jig's already up at that point. Jasnah's not going to let Shallan die, so she makes an attempt to stick to the story, but in reality, a sphere could never fuel a mechanical Soulcaster - we're shown many times that the real devices require a large stone of a specific cut, installed into the device. She might manage to fool a poisoned Shallan (until she's feeling better) or the common people in the room, but to the eyes of a knowledgeable observer, the cover's blown at that point. 

Where is it said Soulcasters need specific cuts? Soulcasters do not work like modern fabrials. They need specific cuts to trap specific spren. All a Soulcaster requires is a gem of the proper color to provide the stormlight to provide the essence. 

Jasnah did exactly what was needed to maintain her story. 

[ccstat]

@Vortaan I know I promised you a response last week, but I'm only now getting to it. You did a great job compiling what we know and drawing connections. 

On 1/1/2018 at 9:43 AM, Vortaan said:

Not all Soulcasters are able to Soulcast every essence [...] In addition, Soulcasters are only able to Soulcast things into an essence that has a corresponding gemstone on the fabrial. This is directly different from how Radiant Soulcasting seems to function, as Jasnah uses multiple essences in the battle for Thaylen city without any particular types of gemstones being noted as being drained.

While I am convinced that Radiant soulcasting does not require polestones of the corresponding essence, I don't think the battle for Thaylen city is necessarily good evidence in support of that. The contents of an entire bank had been scattered across the city and field, so it is reasonable to assume that all of the required gem types would have been available for Jasnah to use, consciously or not. The WoBs that @Calderis shared (this one and this one) are the more convincing evidence. An older WoB from 2013 didn't distinguish between Radiant and fabrial soulcasting, and seemed to suggest that they both required specific polestones. (note also that it is paraphrased). I think that may be the source of any disagreements--it's certainly one that stuck in my mind. 

Quote

StormAtlas (paraphrased)

Why can Kaladin Surgebind with any gem type but Jasnah and Shallan need specific types?

Brandon Sanderson (paraphrased)

A lot of that will be explained as the series comes along. It is really the difference between Soulcasting and the other forms of Surgebinding. It's more a quirk of Soulcasting than it is something that is different about about Kaladin. So you've kind of got it reversed a little bit though; Soulcasting has this additional restriction that the other ones don't.

See also this one from around the same time.

Regarding the metal, I really doubt it is a godmetal. While @RShara is right to point out that godmetals aren't necessarily indestructible, the ease with which the Davar soulcaster was disabled (jabbed once with a sword) doesn't round at all like the resilience we expect to see on Roshar from ancient fabrials. In my mind that includes soulcasters, regrowth, and oathgates, and we've seen that the oathgate mechanism can withstand shardblades (and is at least partially made out of spren).

I can't decide whether my disagreement with this next statement of yours is over semantics or the fundamentals of your theory. You'll have to chime in on your intended meaning:

On 1/1/2018 at 9:43 AM, Vortaan said:

Khriss seems to think that Soulcasting fabrials, medallions on Scadrial, and Honorblades all work by similar principles. What I believe occurs in each case is that the possession of a medallion, Soulcaster, or Honorblade temporarily overwrites the person who is using it's Spiritweb to make them a temporary Metalborn or Surgebinder

I have a strong reaction against your use of "overwrites." Overwriting a spiritweb sounds like Selish forgery, and makes me think that the person is being changed. IMO there is no direct alteration of a user's spiritweb when using a soulcaster fabrial. Rather, they have a temporary connection to the device (for as long as they are touching it), while all of the spiritwebby pieces necessary for utilizing the surge of transformation are contained in the fabrial itself. Which is to say, nothing gets altered or integrated into the user's sDNA, even temporarily. It's like equipping a tool, not granting an ability. (In this respect soulcasters would function differently from the Scadrian medallions, but similarly to the airship fans/primer cubes.)

On 1/1/2018 at 9:43 AM, Vortaan said:

Conclusion: Soulcasting Fabrials create a weak approximation of a Nahel bond

Rather than approximating a nahel bond as you suggest, I think that a soulcasting fabrial operates more as a pre-formed conduit, similar perhaps to aons or the allomantic metals. Burning a metal creates a channel for the power of Preservation, and the molecular "shape" of the metal acts as a filter that shapes what the power will do when it flows through. (See these  WoBs.) A soulcaster is similar, with the device and the associated gems combining to make a channel in the shape of (e.g.) "transform stuff into stone". These channels leak a bit, and that spillage of power is what causes fabrial users to slowly transform into the essence that they soulcast. When one has a nahel bond, the channel is more efficient and more flexible, therefore there is less spillage. I also suspect that any spillage that does occur either gets absorbed by the spren and does no harm, or gets quickly corrected by passive Radiant healing.

I haven't decided quite how I think honorblades fit into this. I could agree that they create something approximating a nahel bond, since clearly the nahel bond was modeled after whatever the honorblades do, but that doesn't actually address the mechanics.

[+Hoiditthroughthegrapevine]

4 minutes ago, ccstat said:

Regarding the metal, I really doubt it is a godmetal. While @RShara is right to point out that godmetals aren't necessarily indestructible, the ease with which the Davar soulcaster was disabled (jabbed once with a sword) doesn't round at all like the resilience we expect to see on Roshar from ancient fabrials. In my mind that includes soulcasters, regrowth, and oathgates, and we've seen that the oathgate mechanism can withstand shardblades (and is at least partially made out of spren).

I have a tin-foil hat type theory regarding Shallan's soulcaster. I think that it might be a fake soulcaster as well. We know from WoR that the only person to use the Davar soulcaster was Luesh, who incidentally was also a member of the Ghostbloods. We know that he had been using the soulcaster to create Marble deposits to fund the political career of Lynn Davar. And it's possible to assume from lack of textual description, that he wasn't turning into the cognitive aspect of what he was soulcasting, which might imply that he was using the Knight Radiant surge of Transformation instead of a soulcasting fabrial. He died in his sleep, and was physically inspected after his death with enough scrutiny to find his ghostblood tattoo, and there was no mention of his body being partially phased into a separate substance.

When Lynn was killed, the ghostbloods were suddenly short a powerful political pawn that they had been cultivating for quite a long time. They are not the sort of organization to let a large investment go without some kind of separate yield. So, after this soulcaster "breaks" (like one chain link is broken), Shallan suddenly comes up with the idea to steal Jasnah's soulcaster. Pretty convenient considering Jasnah is also a figure that the Ghostbloods are actively trying to kill. Kasbal shows up very quickly after Shallan becomes Jasnah's ward to try and utilize her association with Jasnah to get close enough to assassinate her.

So, if this tin-foil hat theory is true, the perceived impermanence of Shallan's soulcaster is not proof that soulcasters are not made out of a god-metal (most likely cultivations).

18 minutes ago, ccstat said:

I haven't decided quite how I think honorblades fit into this. I could agree that they create something approximating a nahel bond, since clearly the nahel bond was modeled after whatever the honorblades do, but that doesn't actually address the mechanics.

I think that the approximation of the nahel bond that the honorblades provide is that they are a connective pathway for the kinetic Investiture to be channeled to do productive work, but unlike a nahel bond, it's not a Cognitive Energy Pathway, it's a Spiritual Energy Pathway. The reason it's less efficient accessing the surge using the Spiritual Pathway, is that a temporary Cognitive Pathway would still have to be created, allowing the wielder of the blade to direct the Kinetic Energy of Investiture. So I think using an honor blade is a two step process, the honor blade uses investiture to create a cognitive pathway connecting the blade to the mind of the wielder so that the wielder can then direct the Kinetic Energy of Investiture to do work. The creation of the connective pathway between the Spiritual Energy of the Blade and Spiritual Energy of the free Kinetic Energy of Investiture (stormlight) is the part that I think the Spren copied when they form Nahel bonds.

[GoddessIMHO]

I was confused by the interlude with the Soul Caster. I'm reading here that she was turning into smoke because she used a smokestone? I don't recall any other mention of the Soul Casters used by the armies to make food turning into emeralds or grain. 

I didn't really get the point of that whole interlude.

[RShara]

39 minutes ago, GoddessIMHO said:

I was confused by the interlude with the Soul Caster. I'm reading here that she was turning into smoke because she used a smokestone? I don't recall any other mention of the Soul Casters used by the armies to make food turning into emeralds or grain. 

I didn't really get the point of that whole interlude.

The ones that make grain turn plant like, and the ones that make stone turn...stony.

The ones Azure has creating food.

Quote

The woman had an inhuman look to her; she seemed to be growing vines under her skin, and they peeked out around her eyes, growing from the corners and spreading down her face like runners of ivy.

The one that turned Gavilar to stone.

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The Soulcaster might have been male, might have been female. Hard to say, with that hood up over their face. The skin beneath was colored like granite, cracked and chipped, and seemed to glow from within. The Soulcaster regarded the corpse, head cocked, as if surprised to find a body here. They ran their fingers along Gavilar’s jaw, then brushed the hair off his forehead.

 

[Cosmé]

On 1/2/2018 at 10:38 PM, 11thorderknight said:

My explanation would be that Shallan knows that garnet = blood, and subconsciously knew the "flavor" of Stormlight she inhaled; therefore, she gets blood. Also makes for a great segue to the suicide attempt.

As a Radiant, she’s able to perform very complex soulcasts like asking a ship to break apart and sink itself (WoR), but as we see in TWoK, she spends the entire book convinced that her Radiant abilities are nothing “special” beyond what normal people can do with the right magical objects. She thinks her blade requires 10 heartbeats to summon. She thinks the soulcaster she acquires can only operate under normal soulcaster constrains. These constraints are probably common knowledge among scholars, because the people that do the soulcasting have to rely on normal people to get them the right gemstones for the tasks they’re performing.

On 1/2/2018 at 10:38 PM, 11thorderknight said:

Regarding Jasnah calling for a garnet - if you think about it, the jig's already up at that point. Jasnah's not going to let Shallan die, so she makes an attempt to stick to the story, but in reality, a sphere could never fuel a mechanical Soulcaster - we're shown many times that the real devices require a large stone of a specific cut, installed into the device. She might manage to fool a poisoned Shallan (until she's feeling better) or the common people in the room, but to the eyes of a knowledgeable observer, the cover's blown at that point. 

If a scholar saw Jasna soulcast without a visible garnet, they’d probably assume she had a hidden one, or just remembered that she had one in a bag or safepouch. Which is the simplest likely solution, from their standpoint: Jasna is hiding a gem, or the lost Radiants that have been gone for thousands of years are back? It’s like witnessing a magic trick in the real world. It’s probably an illusion, not magic, they would think. So, Jasna doesn’t have to work hard to maintain cover. If she told them she was a Radiant, they probably wouldn’t beleive her, especially since they already distrust her for being an atheist.

On 1/2/2018 at 10:38 PM, 11thorderknight said:

With regard to cracking gemstones - mechanical Soulcasters do this, so Jasnah feels the need to periodically do so as well - publicly. Maybe she's learned to "suck" on a stone so hard that it snaps, or whatever.

She could probably just soulcast the gem into a cracked gem, similar to breaking the boat.

On 1/2/2018 at 10:38 PM, 11thorderknight said:

And finally - what's the In-World reason that Jasnah "discovers" the "Soulcaster"?

She’s going to be using her powers, either in a pinch (killing random thieves) or to practice. People are going to see it in a gossipy Alethi court. Best to give them a story they will accept. The fact that her story is offensive to Vorinism actually makes it more persuasive, probably. People will beleive that someone who is already committing heracy will do other thinks, like use a non-approved soulcaster. Anyone who challenged that she was not using a real soulcaster, but instead had something more powerful and special, would be saying that what she, an atheist, had is better than what Vorin ardents have. Probably not a kosher opinion in Vorin society. Of course, that view is harder to maintain now that the Radiants are back, but we see that many still do not trust them.

 

I don’t think she meant to attract Radiants, but the Ghostbloods would probably see through it all. They are an extremely cosmere-aware bunch.

Edited January 12, 2018 by Cosmé

[GoddessIMHO]

Thanks @RSHARA. I had completely forgotten those episodes. This would make Jasnah hiding her "Radiance" even more difficult. It would expected that she too would show these effects.

[digitalbusker]

1 hour ago, GoddessIMHO said:

Thanks @RSHARA. I had completely forgotten those episodes. This would make Jasnah hiding her "Radiance" even more difficult. It would expected that she too would show these effects.

It takes a while, apparently. And the effects we've seen seem to all be associated with the single-substance fabrials. Maybe the Greater Soulcasters don't experience the same side effects.

[MonsterMetroid]

On 1/1/2018 at 10:39 AM, digitalbusker said:

The only part of this I'd quibble with off the top of my head is the assertion that Radiant Soulcasting can fuel any transformation from any gem. In The Way of Kings, when Jasnah is Soulcasting she drains the appropriate gems. And when Shallan accidentally turns the goblet to blood she's holding a garnet.

This is what I was just going to write. I assume that maybe using the correct gemstones makes the transformation easier? I dont know what gemstone shallan had when she talked to stick... But I would assume there still has to be some correlation since gemstones still break from nahel bond soulcasting.

Unless... maybe gemstones break from having stormlight drawn out of them over and over again? we havent seen the other radients do it in exorbitant amounts to the same gemstones yet.

Edited January 12, 2018 by MonsterMetroid

[RShara]

4 minutes ago, MonsterMetroid said:

This is what I was just going to write. I assume that maybe using the correct gemstones makes the transformation easier? I dont know what gemstone shallan had when she talked to stick... But I would assume there still has to be some correlation since gemstones still break from nahel bond soulcasting.

Unless... maybe gemstones break from having stormlight drawn out of them over and over again? we havent seen the other radients do it in exorbitant amounts to the same gemstones yet.

I think it has to do with the speed that the stormlight is drawn out.  Soulcasting (and regrowing Plate) seem to use the stormlight very rapidly, whereas "breathing" it in takes slightly more time.  An abrupt change like that could be what causes the gem to crack.