Why is sentience a "go to" argument for animal advocates and vegans?
I'm not so sure it is. In fact, I'm pretty sure it isn't. At least among the advocates I have read. Some of the very earliest vegan advocates actually constructed arguments that sentience was not at issue. I think most famously and most quoted is Jeremy Bethany. He said something like it doesn't matter if they can think, only that if they can suffer.
Animal advocates and vegans advance the argument that animals are sentient and this means that they should be afforded a particular kind of regard.
Yeah, again I think this is a false premise.
Often this means some kind of interest-based rights, but I get the feeling that for most, sentience just means that other animals feel stuff so we shouldn't be harming them.
This is the crux of it. not if they can think or be self aware or whatever. but that they feel pain.
The problem of harm is one of welfarism - that is, if we can use other animals without harming them (except for the killing part that is) there seems no real reason not to do so if there is a benefit to us from this. In the end I think the argument against this kind of animal use is from a personal sensitivity point of view - someone feels uncomfortable or sad that another animal is killed for food for example. For most people it probably is the case that as long as there is some level of good welfare, the use of animals in this way is fine.
that is more or less why vegans are only tolerant of the the animal welfare movement. We are not against it because it is better than nothing but a lot of vegans feel it is a sop. Although there are a few who speak out against it.
The rights question seems to me to be a bit harder to work out. Why does "sentience" mean we should afford other animals rights? Do activists seriously believe that mice should have rights? Or, at least, the same rights as a cow? When is sentience sufficient to require rights?
Ok, this is a good question and one that is discussed by "real" philosophers. Whole books are devoted to this.
IMHO, "Rights" are a construct. (although I think some philosophers make a good argument that it is real and something bestowed by the creator.)
The Vegan's argument is pretty simple: Animals have the right to life. At least. Once you accept that we can talk about freedom and the pursuit of happiness.
This seems a rubbery question and I am not sure it reduces to any solid argument. No-one can really know what cows or mice think and how they feel about the world, so doesn't the case from sentience really just reduce to welfarism again? Why does it have to be more?
Yes again, I don't know where you are getting this from. From my reading, I understand that vegan philosophers have gone out of the way to avoid a reliance on sentience (or intelligence or emotions). although scientists have shown evidence of some animals being intelligent, and/or self aware, and/or experience a plethora of emotions, there are just too many problems associated with using any of those measurement to assign rights. (1)
Some of the off shoots of veganism have brought this up. Oh, maybe this is where you are getting this from.
Bees have tiny brains, so they must not be sentient, so we can eat honey. Clams have nothing to think about (or with) so we can eat them, too.
Can an oyster feel pain? Well, certainly not like we do but they (and all animals) react to stimuli. We can observe this. So they "feel" something. For most vegans that is all they need to know. To repeat Bethany again, its not whether or not they think. it's that they feel pain.
I can't really get into your other questions because as far as I'm concerned they are based on a false premise. Do they have any meaning at all once you remove the whole sentience part of the problem. Perhaps you could reword the question but then my answer would be something like animals have a right to life.
where these rights come from is an interesting discussion but I'm going to avoid it. But keep in mind that most vegans are Abolitionists: that all animals are not to be exploited.
Yes, I've read a few books about this but mostly it just comes down to someone's feeling that sentience demands a rights based recognition. Is there any empirical basis to this claim that doesn't simply reduce to welfarism?
Yes again, I don't know where you are getting this from. From my reading, I understand that vegan philosophers have gone out of the way to avoid a reliance on sentience. although scientists have shown evidence of some animals being intelligent, and/or self aware, and/or experience of plethora of emotions, there are just too many problems associated with using any of those measurement to assign rights.
So instead vegans fall back basic biology. If its an animal it has the right to life. Actually as I like to do - fall back on the definition of veganism. that people don't have the right to exploit others.
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1. the famous argument is that a pig is smarter than a dog. or even a toddler. maybe a mentally disabled person.