Soulcasting and Forgery

[Gasper]

I have been rereading the SLA and a few things have stood out to me. One of which is when Jasnah's hand sinks into the rock she soulcasts into smoke in front of Shallan and King T. That scene looks very similar to the stamps used in Forgery that sink into the material being forged. Soulcasting is basically feeding an object investure and getting it to change permanently. Forging is basically the same thing only it takes less investure and the effect is less permanent and takes a far longer time to prepare for. My question(s) are this: Is soulcasting as functionally similar to forging as I think it is? And: Could this link be exploited to hack either of the magic systems using the other system, if so, how?

[Calderis]

I think there is a similarity in what you're seeing with the "sinking in." it's bypassing the Physical to touch the Cognitive/Spiritual. 

The actual method of change though... I think is very different.

In soulcasting your changing what something is, with no regard for plausibility and no need of investiture to upkeep the transformation. It is a total, and permanent change. 

With Forgery, you are rewriting an objects history. It is fundamentally the same object or person, but it's history has been overwritten, creating new Connections and hiding others. Plausibility is an issue because the real Connections (in my opinion) are pressing in trying to reassert themselves. 

Soulcasting has a large, upfront cost. Forgery though I actually think takes  more because you have a large upfront cost in the complete write of history, and then a continual feed to maintain those changes. If the stamp is broken, or you leave the region, the Investiture flow stops, and reality reassert itself. 

Edited October 17, 2018 by Calderis

[+Extesian]

Calderis gave a superb description of the difference (I'll forgive his reprehensible laziness in letting autocorrect do 'your' instead so I'll just add a couple of things.

Bear in mind that while soulcasting is more powerful it is more limited. You can soulcast something into a physical thing. But forgery is so ninja. Its even plausible to turn someone into an elantrian or allomancer with it. And as Cal said, forgery is actually high investiture magic, the Sel ones are because of how much the Dor is trying to burst into the physical realm. Which makes sense, it should take a lot of investiture to rewrite Connection so comprehensively. As Cal said that's why it needs to be plausible. Contrast with soulcasting where you are changing the spiritual aspect but (in my view) that can be interfered with by the cognitive aspect resistingthat change (which is why soulcasting can be done by brute force or with less investiture and more convincing).

 I don't think this commonality can be exploited it just reflects cosmere realities- two magics rewriting the spiritual and needing to work within the limitations the cognitive can put on that.