The world out there is a cruel, terrifying place. I’ve heard plenty of wild birds and rabbits scream in agony when killed by feral cats, right outside my window.

That's my general take on the subject. To your point about anthropomorphism, I disagree, I think assessing one's health and bodily integrity is a primal instinct that is most likely shared by most animals. I can't say for sure but I have experienced a lot of body horror myself (torn & deformed limbs) and it was never higher thoughts that prevailed, even in situations without pain (like after surgery).

I sympathize with your view very much, but there's also the agony that results from unconstrained breeding of cats and dogs to consider.

In developed nations feral cats and dogs are often hunted down and exterminated. Even while they live their lives in are often no picnic, whether they're in a shelter or in the wild.

Also, if you have, say, a cat and you don't get them neutered and you let them out what are you going to do with all the kittens? If you don't let them out, the endless confinement could be argued as a form of misery itself.

Then you could argue about having pets at all, but then what about all the cats and dogs that live miserable lives in shelters or are unwanted or abused in other homes? Wouldn't they be better off with you?

There are two different situations, though: preventing reproduction and preventing potentially undesirable hormone-fueled behavior. You don't need to castrate just to prevent reproduction.

I don't think there'd be anything wrong with performing a vasectomy, for example. I'm not sure if there's a similar analog for female animals, though.

Since we are the ones who introduced cats in the first place, we are responsible for the consequences. Violating the bodily autonomy of individual cats is a small price to pay to avoid a population explosion that would ultimately result in the large scale killing of countless birds and other small animals.

Back before we humanly killed animals, an argument could be made

“well it would be better to humanly kill animals as painlessly as possible, versus a painful death. Therefore I’d prefer and support the humane killing”

Now that humane killing is the norm, the act of killing became bad, or at least has become more popular. Obviously the more popular today notion of killing animals being unethical existed back then.

Now we’re onto the argument of consent, regardless of pain (sampling cultures versus not). The next step will be, even having these animals on pastures is unethical, as they cannot be free to go where they want (despite these essentially domesticated livestock being unable to live in the wild without heavy evolutionary pressures I.e. massive death or extinction)

So as “extreme” as it may seem to proclaim that it’s unethical to sample cells from an animal, regardless of pain, I think it’ll surely shift to being more mainstream and acceptable as a viewpoint.

I also think the latter vs in your statement is a straw man, and a poor one at that. To say all livestock grown for meat consumption are “tortured” is a gross generalization.

Sure it exists, but so does ethically raised, pasture raised livestock that are humanly killed (and such practices increasing at a great rate, as grass fed/finished becomes more desirable)

Lastly, this personification of all animals is a misrepresentation of many species. I think there are a few animals we can truly question their sentience (dolphins come to mind), while others I think we can say to a reasonable degree are less sentient than humans, and therefore if killed in the most painless way possible is ethically okay. Obviously this is a philosophical can of worms.

You're thinking about what some others (including newscasters, politicians, etc.) call a slippery slope[1].

I'm wary about criticizing arguments via slippery slope, because.

1. Most optimal-ethically choices sit at a middle-point of a slope when you consider only one dimension; e.g. a limited right to free speech.

2. With respect to shifting mores, one can also consider the situation of empire and slavery. The argument goes that communication and automation respectively were insufficiently developed in the past that these structures were in fact the most empirically ethical, but that they are generally no longer optimally good given today's communication and automation technology. Analogously, as we have better dietary options today, the ethically optimal option might have shifted. That is, the point in the single dimension has shifted because we have shifted wrt the other dimensions.

[1]: note that this is a misuse and misunderstanding about an actual slippery slope fallacy. In the valid usage, the slippery slope is exhibited completely within the fallacious argument so that the evidence is exaggerated to support the conclusion when the conclusion actually does not follow. In the misuse, one worries that the proposed conclusion would lead to a change in what people think is accepted, such that bad things become accepted.

I'm aware, and wasn't trying to say that (hence "trillions" instead of "all").

I just said that, for an average (say) cow, if you assume current trends continue for decades and centuries, with no lab-grown alternatives, it is likely that over time trillions of cows will be raised in cruel conditions and killed for food.

While this is happening, there may also simultaneously be billions (or more) of cows that are raised with a lot of open space to graze on and are treated well before being killed. Relative percentages aside, it's still a high absolute number of animals tortured and killed.

The only way for this massive death/extinction (within the current system) is if everyone adopts this vision overnight. What's more likely to happen is by people eating less and less meat, animals will be less and less bred by farmers. Probably something similar to when cars supplanted horses in cities.

Is it? As far as I know, most animals are "factory farmed" in conditions so inhuman that some countries have laws against... documenting their conditions on video.

But you can turn this also the other way round: If we are all, humans, cows and trees, ultimately one living creature, why should we worry more about dying cows than we worry about our dying skin cells or dying white blood cells that defend us? We are killing more awareness by drowning our attention in cheap entertainment and we are enduring more suffering by not delivering food to the starving children, and adults around the world.

We are all one conglomerated living creature - the many twisting branches of the LUCA - but over time different aspects of this creature emerged with varying levels of complexity and information processing capability. One could argue that a lot of our atoms come from stars, so why treat ourselves any differently from stars, or that all matter and energy in the universe is just the offspring of a unified low-entropy blob at the Big Bang, so what difference does any of it make anyway.

There is some logical truth to this reasoning, but if we assume sentience to have at least some effectively non-illusory component, then I think it makes sense to consider sentient systems very differently from non-sentient or almost-non-sentient ones.

Puzzles don't matter. The world doesn't like them much and therefore doesn't do them much. What they do like is tasty food. So that's the route to conversion. Not the puzzles.

It's quite a terrifying thought, to be honest - maybe because the animal in question is very much conscious and intelligent.

I'm never quite sure whether or not Douglas Adams wrote it for comedic effect or to provoke some deeper discussion.

Might as well be both.

The current scientific understanding is that most animals are so much more sentient and conscious than all plants that it makes sense to give moral consideration up to some threshold lying between the two. (With unicellular organisms even lower.) There are some animals (e.g. jellyfish) that as far as we know appear to reside below the plant threshold, in which case I'd consider it okay to kill and eat those animals.

Isn't that a contradiction? You know that mother cows are slaughtered after they're done producing milk, right? And the male calves are mostly slaughtered immediately.

"I'm a celibate prostitute"

I think veganism is much closer to being ethical