Or, for that matter, that you can't allow or prevent critters from having sex with other critters, which by the "they lack an adult human mind, therefore sex = abuse automatically" line of reasoning would be equivalent to pit fighting.
Err...no? This is similar to two underage persons having sex: while they are incapable of consenting, they're also incapable of bearing punishment for their acts. And as with underage people, they can be legally prevented from going at it, even against their will.
That's not actually the case, though; as mentioned, most laws make no distinction between an of age and underage perpetrator, and have to be augmented with exceptions where they exist, which isn't anywhere near universally.
The reasoning for it is also not "they're unable to be punished for this heinous act," as far as I'm aware, unless you mean "incapable" as "well that's messed up we shouldn't do that." Else, again, minors would be incapable of being charged for any sex-related offenses, which isn't the case, and possibly be exempt from being charged with
any offenses, which
certainly isn't the case.
You'd also expect there to be some kind of prevention mechanism in that case, since even though neither party can be punished they're still causing each other harm. But I'm unaware of anything like that outside of normal parental authority; as far as I've heard, sex is legal or illegal and parental or stranger intervention is legal or illegal, with no connection to each other at all. That is, you can't abduct or assault a minor to prevent them from having sex with another minor in the same way you could to prevent them from assaulting said minor or going to a party with said minor, unless them having sex with each other is illegal or preventing them from having sex with each other is legal in the same way that assaulting each other or going to a party together would be.
E: doesn't cruelty imply violation of consent? Like, if your cow clearly communicated to you that it wanted you to, I dunno, remove its leg or something, it would be questionable but not cruel to comply. But it is unable to communicate this, therefore we assume it does not consent.
That reasoning doesn't work for a lot of things that we allow and does work for sex under a lot of circumstances. Pets can't communicate that they want to go to the vet, but we don't assume that means they're not consenting; indeed, I'm pretty sure we don't care if they consent, because in
that case we just shrug and assume the human has authority to make important decisions in their pet's stead. When we're talking about docking ears, things split off a bit more, with some people all of a sudden deciding they
don't have the pet's best interests at heart and others figuring they can do what they want to their property and so on.
Conversely, if an animal communicating that it wants something is consent, I imagine quite a lot of bestiality is no longer cruel.
I know, I know. I am just making an assumption that underage persons bear very limited legal responsibility in most places.
Not the case as far as I'm aware. You Europeans and your weird civility.
Anyway, I am not really arguing that my views are to be enforced as law. My case here is more that I do have a more or less clear idea of what kind of harm I would consider acceptable for myself to bring to an animal, and what kind I would not. I claim no consistency except internal (with regards to the homosexuality thing). Humanity as a whole is rather inconsistent with this, as with most other things, I agree.
If you're just speaking for yourself then a lot of this stuff is extraneous, but oh well.