Well, Zas, you and I have sort of discussed this on and off on various theory threads, but now it is time for me to make a comprehensive reply. It should be noted that I, of course, sponsor the Principle of Intent, so this reply will probably end up being a "You're wrong, my theory is right" sort of thing... Oops. I’ll try and soften it, but hopefully you don’t take it personally

For readers, I'll sum up the differences between Zas's and I's theory, though I have not written a comprehensive article on mine. (Oops)
Zas separates things into Human Power, Shard Power, and Power of Creation. Shards are gateways to the Power of Creation. Shards "flavor" the Power of Creation to a distinct intent. I'm oversimplifying the theory, of course, but you can all scroll up

I, however, support the idea that Shards are literal fragments of Adonalsium. They are the highest level of power. Adonalsium is the power of creation, and Shards are a portion of that power. The Shattering separated Adonalsium's power into sixteen distinct intents/powers, sort of like the sixteen distinct abilities of Allomancy. In this conception, Zas's Shard Power and Power of Creation are identical. Additionally, there is not a special classification for Human Power.
Okay. Now let's discuss these.
Firstly, nowhere is there any explicit distinction between Human, Shard, or Power of Creation. That's my biggest problem with this basic idea. Let's discuss the largest piece of evidence for this theory:
3. The powers of Ruin and Preservation are Shards of Adonalsium, pieces of the power of creation itself. Allomancy, Hemalurgy, Feruchemy are manifestations of this power in mortal form, the ability to touch the powers of creation and use them. These metallic powers are how people's physical forms interpret the use of the Shard, though it's not the only possible way they could be interpreted or used. It's what the genetics and Realmatic interactions of Scadrial allow for, and has to do with the Spiritual, the Cognitive, and the Physical Realms.
Condensed 'essence' of these godly powers can act as super-fuel for Allomancy, Feruchemy, or really any of the powers. The form of that super fuel is important. In liquid form it's most potent, in gas form it's able to fuel Allomancy as if working as a metal. In physical form it is rigid and does one specific thing. In the case of atium, it allows sight into the future. In the case of concentrated Preservation, it gives one a permanent connection to the mists and the powers of creation. (I.e., it makes them an Allomancer.)
So when a person is burning metals, they aren't using Preservation's body as a fuel so to speak--though they are tapping into the powers of creation just slightly. When Vin burns the mists, however, she'd doing just that--using the essence of Preservation, the Shard of Adonalsium itself--to fuel Allomancy. Doing this, however, rips 'troughs' through her body. It's like forcing far too much pressure through a very small, fragile hose. That much power eventually vaporizes the corporeal host, which is acting as the block and forcing the power into a single type of conduit (Allomancy) and frees it to be more expansive.
I’m going to parse this line by line. I’m sick of using quote blocks, so I’ll just bold stuff.
The powers of Ruin and Preservation are Shards of Adonalsium, pieces of the power of creation itself.This explicitly states that the Shards of Adonalsium are of the same power as the power of creation, so the distinction with Shard Power and Power of Creation is a false one.
The only way there is such a distinction is if the Shards of Adonalsium are not all of Adonalsium. Meaning, you can have sixteen pieces of the power of creation, but that may not be every piece of Adonalsium.
However, you’d be hard pressed to show there is, in fact, another piece of Adonalsium, much less a power more infinite than the Shards, like Zas suggests.
The two things that are apparently of the Power of Creation: Allomancy and AonDor. I would argue that, given that Aona and Skai are dead, there is plenty of energy to make up the Dor. What the makeup of AonDor is exactly is another story. There’s a bunch of energy to go around without inventing a higher level of power.
In fact, I would argue that Sazed’s words about Adonalsium implies the opposite, that there is no higher power of creation.
Even now, I can barely grasp the scope of all this. The events surrounding the end of the world seem even larger than the Final Empire and the people within it. I sense shards of something from long ago, a fractured presence, something spanning the void.
I have delved and searched, and have only been able to come up with a single name: Adonasium. Who, or what, it was, I do not yet know.Okay, so Sazed hasn’t searched for that long, but he’s used two Shards to figure it out. You’d think if there was an ultimately infinite power higher than his own Shards, he’d find it, like a massive bronzepulse. Instead, Adonalsium is a mysterious thing. Sazed has two pieces of the story, but he’s missing fourteen.
Plus, it’s a fractured presence, as you’d expect when you chop Adonalsium into sixteen Shards.
Considering that, in Zas’s conception, the Power of Creation is directly related to Allomancy, you’d think Sazed would figure it out, as if it was a huge, blasting neon light. “Look, infinite power!”
The fact that he
didn’t is very telling. Already, I feel this theory is mortally wounded.
Allomancy, Hemalurgy, Feruchemy are manifestations of this power in mortal form, the ability to touch the powers of creation and use them. These metallic powers are how people's physical forms interpret the use of the Shard, though it's not the only possible way they could be interpreted or used.Look at the first two sentences. It’s hard to deny that Brandon is equating Shard with the power of creation.
It's what the genetics and Realmatic interactions of Scadrial allow for, and has to do with the Spiritual, the Cognitive, and the Physical Realms. There we have it. The real distinctions are in Realmatic interactions. What is specific to Scadrial are Ruin and Preservation. These two things combined are what create the Metallic Arts.
I feel that Human Power, Shard Power, and Power of Creation are fictious categories. I do not feel that we should use fictious categories on a theoretical basis. If they were real categories, they would have vast influences. Instead, things are categorized by Physical, Cognitive, and Spiritual Realms. These
absolutely have far reaching consequences. Whatever Brandon meant by “Realmatic interaction,” we can only guess, but it’s much more fundamental than Zas’s triad of categories.
Indeed, the
Three Parts of Magic theory states that every magic system has three elements. I would go further (as the commentors in that theory already have) and say that
everything has a Physical, Cognitive, and Spiritual aspect. Humans certainly do. Rocks, or goblets, have weaker Cognitive aspects, but they are still there.
Another Realmatic theory involves the idea that
Shard power creates sentience. Why is that fact problematic for the Power of Creation theory? Well, because sentience is neither in Human Power, nor Shard Power. They are a weird hybrid. In Zas’s theory, this is an ambiguity, but in Realmatics, we call it the Cognitive Realm and call it a day.
Does there need to be a distinction between Human and Shard? I don’t think so. Ruin built humans in the shape they had seen before. As such, creating humans is doable from Shards. Sure, there are Realmatic considerations as well as a Shard’s intent which causes diversity between planets, but humans have a Physical aspect (duh), a Cognitive aspect, and a Spiritual aspect with the fragments of Preservation and Ruin in someone. Humanity, then, is neither “Human” nor “Shard” power. The distinction between the two are not useful.
“But wait!” I hear you say, “what about Feruchemy? Surely that is a Human power.” Yes, but that can just as easily be described from a Principle of Intent background. Feruchemy works within Physical attributes because the Shard’s intents have a “balance,” and thus, the
Realmatic interaction should then be a balance with Spiritual aspects. What’s left to use? Physical attributes.
You could say that I’m inserting a Shard’s intent into the words Brandon said here, and you would be right. But he said “the Realmatic interactions Scadrial allows for.” It’s hard to make a bigger distinction between planets than the Shards on a given world, and their intent.
Moving on.
Condensed 'essence' of these godly powers can act as super-fuel for Allomancy, Feruchemy, or really any of the powers. The form of that super fuel is important. In liquid form it's most potent, in gas form it's able to fuel Allomancy as if working as a metal. In physical form it is rigid and does one specific thing. In the case of atium, it allows sight into the future. Not much to say here. Zas calls this Shard Power, but I’m not sure the category is useful.
In the case of concentrated Preservation, it gives one a permanent connection to the mists and the powers of creation. (I.e., it makes them an Allomancer.) Here we have a reference to the mists and power of creation as separate. But, of course, the mists are a part of the power of creation.
So when a person is burning metals, they aren't using Preservation's body as a fuel so to speak--though they are tapping into the powers of creation just slightly. When Vin burns the mists, however, she'd doing just that--using the essence of Preservation, the Shard of Adonalsium itself--to fuel Allomancy. When Vin burns the mists, however, she'd doing just that--using the essence of Preservation, the Shard of Adonalsium itself--to fuel Allomancy. Doing this, however, rips 'troughs' through her body. It's like forcing far too much pressure through a very small, fragile hose. That much power eventually vaporizes the corporeal host, which is acting as the block and forcing the power into a single type of conduit (Allomancy) and frees it to be more expansive.Tons to talk about here. Zas says:
So there is a distinction here. We see that there is a difference between burning the Mists and burning metals. I believe that when you burn metals, you are using Preservation as a "gateway" to the Power of Creation. The closer you are to Preservation then, the closer you are to the Power of Creation.
Okay. Now we’re getting into deep stuff here, and core of the conflict. Earlier from the paragraphs I’m dissecting, Brandon said:
Both gods could, if they wanted, fuel all of the metallic arts. Preservation is stronger at fueling Allomancy, Ruin stronger at fueling Allomancy or Feruchemy when it has been given via a spike. Both are balanced when it comes to Feruchemy. But this rarely comes up in the books, as it required expending power in a way that the gods were hesitant to do.To which Zas realized:
They don't want to use their own power. Can you imagine if Preservation used all his power to fuel all the Allomancers? He would be powerless!
Back up to the dissection:
So when a person is burning metals, they aren't using Preservation's body as a fuel so to speakOkay, they aren’t using Preservation’s body as a fuel. But look at the context of what is said. Brandon gives an example of “not using Preservation’s body as a fuel” to “directly using Preservation’s body as a fuel”. In context, of course Allomancers aren’t using Preservation’s body as a fuel: they are using the metals as a gateway to access the power of creation. And in my conception (and Sazed’s, it should be noted), that is Preservation.
This is quite different from mist-burning. The “burning” is actually “holy crap Preservation power ow ow.” Before, metals had to do with the Realmatics of Scadrial, in that they were a focus for Ruin and Preservation. They provided discrete powers. However, Preservation-burning is like this:
When Vin burns the mists, however, she'd doing just that--using the essence of Preservation, the Shard of Adonalsium itself--to fuel Allomancy. Doing this, however, rips 'troughs' through her body. It's like forcing far too much pressure through a very small, fragile hose. That much power eventually vaporizes the corporeal host, which is acting as the block and forcing the power into a single type of conduit (Allomancy) and frees it to be more expansive.So, whereas burning metals is a perfectly easy way of shoving energy through a “very small, fragile hose,” mist burning has much more pressure. It’s inefficient by comparison. If this were a heat engine and we were in physics, there would be excess “heat”. Mist burning is “expensive” in that it is harming the Physical aspect of the host. It’s expensive because normally, when Shards do this, it is picking up a new host.
Mist burning is cheating.
We never get Vin’s viewpoint of when she was fueling Elend’s metals. Using Realmatic considerations, we’re breaking the need for that Physical focus. That’s ludicrously expensive, in terms of the cosmere, just as creating a Cognitive element to humanity was expensive to Preservation.
Compared to doing it the normal way, of course a god wouldn’t want to, unless they could avoid it.
Ultimately, Spiritual power goes a long way. That Cognitive power that Preservation made? It was a
small effect, compared to the vastness of a Shard. I’d imagine things go like Spiritual -> Cognitive -> Physical, in order of “energy.” Creating Cognitive power is harder than Physical power.
When people do Allomancy the proper way, it’s a speck in a vast pile of Preservation’s power. A little bit, manipulating the Physical Realm? Who cares? (And, if what I suspect is true, that power that is burned as Allomancy regenerates, as the Well of Ascension and atium does)
And besides, there are far too many instances of saying “Allomancy is fueled by Preservation” to say that Allomancy is using a power external to Preservation. To wit, MB3 annotations chapter 38:
Allomancy is not fueled by metal; it is fueled by Preservation. The metal is the means by which a person can access that fuel, however. If there were another way to access it, then the metal wouldn't be needed.
In fact, that annotation fully describes how it works:
First, to these forces, energy and mass are the same thing. So, their power can take physical shape—as Preservation's did in the bead of metal Elend ate. Second, there is a bit of Preservation inside of all the people—and it's this that allows the people to perform Allomancy. It needs to be awakened and stirred to be of use, but when it is, a proper metal can draw forth more of Preservation's power. It's like the metal attunes the bit within the person, allowing it to act as a catalyst to grab more power.
So there you have it. It does not seem that Allomancy is fueled by a separate power of creation.
Moving on. Zas’s quotes.
So Chaos said this, and it really started to bug me. Why? Because Ruin, while he's ruining the planet, does have limits. He can't just instantly destroy the planet. Chaos believes that this is because there is a net limit power that Shards have. I believe that is true, but that there is also a greater power, a limitless (or nearly so) power.
Yes, I do believe there is a net limit to the power Shards have access to. Zas says this is Shard Power. Sure. However, at the same time, Ruin was never omniscient or all-powerful.
I believe Ruin’s inability to do so was limited by the lack of atium and Preservation was, by default, pushing back at Ruin’s force. In addition, there must surely be a Cognitive limit to what Shards can do. Even Sazed, as evidenced by Alloy of Law, cannot speak to Wax in a large scale. He needs the mists to be able to influence things easier. Why? Well, obviously only so much can be done with the mind controlling a Shard.
So really, you can have an effectively limitless Spiritual aspect to a Shard but still not get a infinite power, because as much as one’s mind is expanded by a Shard, there are still Cognitive limits.
[[It’s like flaring a metal. Eventually, you hit a limit. You know, that Shard/Allomancy analogy is pretty good. Just like Allomancy, you can only exert so much of your Cognitive “will.” This could be why flaring has a limit as well. But I’m digressing.]]
Indeed, Mistborn 3 Annotation 55 says:
The mist spirit is, as the next epigraph explains, the remnants of Preservation's mind. I don't delve into it too much in this book, even the epigraphs, but Preservation's consciousness is indeed separate from his power. However, his consciousness itself has a limited power. And that is what he used to bind Ruin.
So, in review, I think it is clear that the distinction between human and Shard power is not a useful one. It’s ambiguous. Consider Hemalurgy’s ability to create koloss and kandra. In the Ars Arcanum, those four Hemalurgic powers are “human” powers. But, as MB3 annotation 39 says, these are parts of Preservation’s power. Granted, that Ars Arcanum is in world, and therefore not entirely accurate, but at the same time I’m hard pressed to find an instance where a human/Shard power distinction is actually important. I’ve discussed Feruchemy, and how that can be explained in a more illuminating way using the Principle of Intent.
The one you like to make is Breath. Zas, you’ve mentioned a couple of times about how Breath are human power, rather than the Divine Breath of the Returned. I’ve said that Breath are simply like the pieces of Ruin and Preservation inside people on Scadrial, or, specifically, make up the pieces of their souls. You’ve said that it’s an effect of Endowment on humanity, rather than Ruin and Preservation giving people that power. (The example used is if, say, Endowment went to Scadrial, they would start to get Breath)
Well, I’m just not sure there is a big enough distinction. Practically speaking, people on Scadrial have souls that are pieces of their Shards. Breaths are very much like this for people on Nalthis.
At the end of the day, people on Nalthis could get their Breath the same way people on Scadrial get their souls: through some mysterious interaction via breeding. The mechanism feels very much the same, so using Breath as a big distiction isn’t too convincing to me for this theory.
So there isn’t really a Human/Shard power separation. The evidence doesn’t support it.
And a power of creation separate from the entirety of the sixteen Shards is unverified by even our most powerful of viewpoint characters (Sazed). I would argue that such a thing does not exist.
Instead, consider the idea that Shards are... Shards of Adonalsium. Pieces of the power of creation. That’s kind of what you’d expect them to be, with names like that. Of course they are pieces of the power of creation.
Is there a possibility there is a piece of Adonalsium that are not Shards (and not Shard derivatives, like Splinters and Slivers)? I suppose there is. But as I am writing this, I do not find that to be a likely possibility. As always, I could be wrong, but hopefully, my logic works for you.