We have come a long way from Descartes argument that animals are no more than automata. Which supported our unabashed exploitation of countless species.
It is now abundantly clear that animals have their own phenomenological experience of the world, and their intelligence is part of a continuum, shaped mostly to survive in their niches. And some species demonstrate a higher level of general intelligence - something in which we are quite easily the best.
Although, it's worth noting that some cultures (Buddhists or Jain's for example) did give animals their due with respect to their lives and intelligence.
Descartes couldn't figure out how humans weren't automata either. That's where his explanations start getting supernatural, and not particularly insightful. Any kook can babble on about an invisible pineal gland soul-thread.
edit: I think the interesting thing for people is how insight like Descartes' becomes useless when he tries to distinguish us from automata.
It's not abundantly clear what the ability to have phenomenological "experiences" means in relation to our moral values regarding what we shouldn't do with the creature. I mean, we do have moral values about animal rights, but they start with the animals we actually relate to (pets) and are in essence human rights by proxy. Then out of a sense of consistency we try to extend these rights to all the wild animals, many of them busily eating one another and blatantly not caring about nice things or participating in our value system.
As far as I can tell, current theories are that animals are also somewhat conscious and intelligent, but that we're all, including humans, automata, with zero or near zero free will.
I don't even know what that means or why it worries people, I think it's a big red herring. (And near-zero is a confusing concept.) We're machines that make choices, spontaneously and deterministically (which is not a contradiction). People fretting about free will are getting caught in some kind of category error that confuses the physics of time with being controlled by an invisible tyrant.
Law is one practical aspect of free will that people generally don't talk much about.
For example, criminal law generally assumes people have free will, and thus should be responsible for their actions. If we take the stance that people are in fact merely deterministically doing what they are fated to do given circumstances, some of the punishments doled out to convicts might make people feel uneasy. (Eg. if being poor made the person commit theft... shouldn't we tackle the issue of poverty instead of locking up starving people?)
Contract law also assumes people are free to make agreements. Like, signing a contract with onerous terms because that's the only option a person has to avoid something worse.
In short, free will provides a kind of cop out for moral philosophers to blame individuals for their own failures. You may or may not agree with this approach, I'm not advocating for or against, but anyway that's one of the practical consequences of free will.
Funny, to me it seems people talk about this one a lot. And the same answer applies. Yes, we have free will and responsibility (because we can respond). Also yes, we do what we do because of physical mechanisms which means you could say we're "fated" (leaving aside the irrelevant complication of chance and probability).
However, the law is only concerned with people doing (codified) wrong. It lets people off for being insane, because dealing with insanity falls outside of its mission. And similarly it can let people off on compassionate grounds, if for instance they stole food due to being hungry due to poverty. Punishing people for bad luck isn't its mission either. And a contract signed under duress isn't supposed to be valid, because the law's mission isn't to enable formalized bullying. Of course in reality the law is sketchy, lacks compassion, fails to recognize forms of duress. But generally speaking the idea is that it's restricted to the bad things a person freely did, as opposed to things that happened to the person.
So then you might say, well, do we freely do anything at all, because it's all just physics and mechanisms. But a lot of the mechanisms are in our brains, thinking sanely (if immorally), so yes, we do act freely, when not coerced.
It's important to separate the part of fate which is the things we're probably going to think, which is our responsibility, from the part of fate which is the things that the outside world is probably going to do to us, which is outside of our responsibility.
I'm not sure I get your point -- it looks like you're starting from the conclusion that people do have free will, which of course does not create problems I mentioned.
What I was trying to say is that if one believes determinism is incompatible with the concept of free will, then they cannot think the law is fair because nothing has free will. And I'm hypothesizing that people who think that way might be a bit queasy about determinism etc.
FWIW, I personally believe free will exists for reasons outside the scope of this discussion, and I doubt it's necessary to conclude first whether it exists or not to get my original point across...
It is now abundantly clear that animals have their own phenomenological experience of the world, and their intelligence is part of a continuum, shaped mostly to survive in their niches. And some species demonstrate a higher level of general intelligence - something in which we are quite easily the best.
Although, it's worth noting that some cultures (Buddhists or Jain's for example) did give animals their due with respect to their lives and intelligence.