Younger vs Older Breaths

[StanLemon]

The Sunlit Man seems to have given given us an explanation why Breath from children is considered better than from older people. 

The Investiture thresholds are similar in concept to Heightenings. According to Sigzil as long as he retains certain levels he gains abilities, and while those abilities do use Investiture, it's only a tiny amount. Applying this logic over to Breaths and Heightenings, the benefits of Breath, even just one very slowly use up the Breath.

This difference between a young and old Breath is probably small enough that it doesn't make much of a difference between dozens or maybe even hundreds of Breaths, but on the scale of 10s of thousands it like Susebron, it could make enough of a difference to explain why they get their Breaths from children for the Returned.

[Lego Mistborn he/him]

That makes sense, and if true, helps clarify the nature of breaths.

Previously, as I understand it, breaths were thought to act as keys to investiture because they (mostly) didn't get spent. If instead they slowly weaken, then this makes more sense for them to be considered a unit of investiture.

Nice catch.

[Firesong she/her]

22 hours ago, StanLemon said:

The Sunlit Man seems to have given given us an explanation why Breath from children is considered better than from older people. 

The Investiture thresholds are similar in concept to Heightenings. According to Sigzil as long as he retains certain levels he gains abilities, and while those abilities do use Investiture, it's only a tiny amount. Applying this logic over to Breaths and Heightenings, the benefits of Breath, even just one very slowly use up the Breath.

This difference between a young and old Breath is probably small enough that it doesn't make much of a difference between dozens or maybe even hundreds of Breaths, but on the scale of 10s of thousands it like Susebron, it could make enough of a difference to explain why they get their Breaths from children for the Returned.

I feel we already got the answer, Brandon said the aura around people with Breaths uses the same mechanism as Stormlight Leaking, due to the Second Law of Investiture Thermodynamics. Which means that they slowly give off parts of their Breath over time as that aura, which depletes it, albeit very slowly. 

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scottwo

Is the radiance of the Returned, or people with Breath, is it like Stormlight coming off of people? Or is it a different concept?

Brandon Sanderson

It's a similar concept with different magic systems.

This is at least one big part of the answer. Investiture likes flowing from a place of high Investiture to one of low Investiture. Thus Breaths try to radiate outward, but the radiation is very weak when you have one. But as you get more and more, that radiation grows stronger as the differential between yourself and the environment grows.