(Continued from the Ocho (IDW) talk page, as my draft response was getting bigger than I expected.)
The problem is arbitrary definitions of mutation. I've understood it to mean simply to change forms more or less permanently, whether by gradual genetic mutation, abrupt genetic mutation, a Turnstone, an enchantment (like with Ocho), or other means. If this is going to be a point of contention as far as categories are concerned, we need to assess the entire franchise's lore and answer the question, "What is a mutant?", because we can't adopt an arbitrarily narrow definition that will end up excluding anyone whose change was considered to have made them a mutant. This becomes an issue when we classify not just by individual continuity, but across all continuities—if the creative minds of one continuity differ on this question from the creative minds of another continuity, that distinction won't necessarily be obvious to editors or readers who may be aware of more than one continuity's lore strictly as audiences of the end product.
In this case, I can accept that Sophie didn't necessarily consider Ocho a mutant when she co-designed her. But if other mutants have been similarly made the way Ocho was, then what she considers, with all due respect to her creative authority on the matter, is still an incomplete picture here.
And just four days ago, another user sought my opinion at Thread:250643 on whether Rise of the TMNT was abandoning the franchise's trend of science fiction mutations in favor of magical mutations, because, and I quote, "Splinter and the Turtles are no longer mutants created by science, they are magical beings." I responded to their question there. But the point here is that even the Rise turtles have been intuitively judged by some of their audience as having been changed by a magical potion rather than by a sci-fi chemical, which would seem to put their mutations on par with the Turnstone and other magic-based mutation plot devices.
Regardless of what that is or not, when the author says "not a mutant", they're not mutant. On top of that, I don't know if you can call it "arbitrary" when it's the rules the franchise has run on since day 1. Mutant/mutation in a fictional universe is what it is in a fictional universe, regardless of real world or other fictional universes. You might as well start calling werewolves and the like mutants, if you're going to go by the logic that literally every transformation is a mutation.
Rise literally calls the Turtles and others transformed the same way, mutants. The substance they are transformed is called mutagen.
I suppose there are instances in which a magical usage can be considered mutation but that would be literally only in cases where it is called in-universe or by a creator to be mutation, such as the Transmutador Yin-Yang.
I've never been entirely convinced werewolves can't be considered mutants. But you make some good points here. All right. It appears there may still be some confusion over Jess Harley's status, but I will agree that, for the interests of categorization, Ocho is not a mutant. I'll edit accordingly.
You know, I do realize that sometimes I don't always think of these things in an ordinary manner that would be considered straightforward. I'm not exactly a lay person, and it's not always easy to think outside the boxes of my own training. Some things that people see as complicated, I see as plain, and some things that people see as plain, I see as complicated. Sometimes it...helps for another person to remind me of the steps I haven't considered and why they are necessary.
In regards to how I approach the word "mutate," my perception is perhaps skewed by both linguistics and computer science, two fields of study I'm heavily invested in. In linguistics, "mutate" is from Latin mutare, which means "to change." And in computer science, the terms "mutation" and "mutable" are used to describe the programmatic altering of data structures stored in live memory. All this has made me treat "mutate" as a synonym for "change," and "mutant" as a synonym for "changed." Sometimes I forget that meanings of words like that can be more contextual and layered.