Along the lines of BioChromatic Breath being akin to a person's soul, how would a Shardblade react to someone who does not have any Breath, would it cut them like an inanimate object?
No. Remember, one of the things with Breath is I consider Breath to be a part of someone's soul, but it is the extra part that the Cosmere has that non-Cosmere doesn't have. I don't know how far I want to lean into this, but there is definitely a part of me that thinks that Drabs, people who have given up their breath on Nalthis, are just like people from our world. That's what they are, that if we went to the Cosmere we would all be Drabs. Even on planets that aren't Nalthis, where you can't take part of that and give it away and things like that, people are invested. They are invested generally more than here.
Why do I do this? There's a couple reasons. One, it's really convenient for some narrative reasons. A lot of books I'm writing are these kind of action-adventure stories, and can human beings actually take the punishment that is delivered, let's say to Adolin in the end of Oathbringer? *noncommital negative sounds* He doesn't come off well from that, but could a human being really take that? I go back and forth. Humans are capable of some pretty incredible feats, particularly with adrenaline driving them, but my kind of blanket answer is everyone in the Cosmere has got a bit more Investiture; everyone's got something like Breath. Nalthians have something kind of extra special because they can use it in different ways, but everybody's got something like that.
It's leading to the fact that for instance, I highlighted this in the books, this part is canon: There are things about Rosharans that make it so that a lot of diseases have trouble getting a foothold. You do not have the bubonic plague on Roshar. You could maybe say this is because they are not living in close enough proximity to mammals for diseases to hop species as happens on our planet, which is a pretty valid point. Things that affect a horse or a cow (a lot of different diseases from cows come to us), things that affect a cow are much more likely to be able to affect a human than something that affects a chull being able to affect a human. Totally valid, but I also think that there is something more going on here.
This allows me to do fantasy stories where... In Warbreaker we don't have to be worrying about the next outbreak of smallpox, which legitimately they probably would have to be worrying about. It means that, while this is kind of a trope that people, trope is the wrong term, but that people in the past did not have as bad as teeth as we assume that we do because they did not eat the levels of sugars and starches that we do. Investiture also in the Cosmere means that you're not going to... Dalinar probably would not have a full set of teeth, even without being punched in the face and stuff, if he were a human from Earth. But on Roshar he's got just a little bit extra vitality, a little bit extra something, just like everyone on the planet, that is making him a little tougher and making him a little more disease resistant and some of these things. It makes the stories more fun for me to tell and also gives us some suspension of disbelief on some of these things. You do not have to worry about smallpox outbreaks on most planets. You do have to worry about catching the curse of the Elantrian disease and being thrown into a prison city, but smallpox, not as big of a deal.
Yeah, but you don’t have to worry about that too much anymore.
No, but I'm saying you could have to worry about things like that. Magical diseases, totally on the board, but the big plague they're dealing with in Roshar is the common cold that got brought across by some of the members of Seventeenth Shard, and that's going to die out pretty quickly. They will get over it and their immune system is... The common cold has come over multiple times before for reasons like that, colds just from another planet. Roshar, they've got three Shards. Basically if you want something like this to happen you go to a planet that's not quite as highly Invested where they might have a few more diseases, you pick one up, you bring it, and it spreads a little bit but then it dies off. That sort of thing happens a lot in the Cosmere. You do not have to worry about during the space age that people are going to be bringing lots of diseases across planets.