Peter Watts – the brilliant science fiction author and all around awesome human being – posted on his blog about a lawsuit filed by PETA to classify killer whales on display at Seaworld as ‘slaves’ and have them released.

There’s an increasing body of evidence suggesting that killer whales have intellectual and emotional intelligence levels comparable to our own. In fact there are a multitude of animal species that are, for all intents and purposes, sentient and intelligent. The BBC has even created an entire TV series exploring that premise.

The point PETA is making is that due to the level of intelligence possessed by killer whales, keeping them locked up for human entertainment is equal to slavery. The lawsuit was apparently entertained by the courts for a while before being thrown out on the grounds that slavery laws apply only to human beings, not animals.

Now that raises an interesting question, one that Watts also addresses on his blog. That question is about where we, as the dominant life form on the planet, draw the line when it comes to awarding rights? Does a sentient being have to be human for it to have appropriate rights? Is sentience – and thus the ability to suffer – in itself not enough?

It seems that our legal system requires more than mere sentience. The ability to suffer is not sufficient to award a creature any rights to protect it from harm. But here, too, humans have double standards. When common pets are abused by their owners, many countries do have laws in place that can protect the animal and punish the human.

However this all seems predicated on physical abuse only. Mental abuse – such as invonluntary incarceration and being forced to put on shows for the entertainment of your captors – does not apply to animals, or so the law is interpreted. Yet is that kind of suffering any less?

Also, it raises all kinds of questions about how humanity will deal, at some stage, with artificial intelligence. This will be yet another form of non-human sentience, so what rights will apply to AI? If we’re being consistent, slavery and mental abuse will, too, be perfectly allowable then.

And, to take the thought experiment even further, what about intelligent alien lifeforms? Do they have any protections under human law? Again, if we’re being consistent, our laws should only apply to aliens inasmuch as they apply to cats and dogs.

What this all boils down to is that our current perceptions of what is right and wrong are, understandably, entirely human-centric (and even that is a recent development – it used to be entirely rich-white-male-centric). It might be time that we continue our progression as a species, and start to expand our legal and societal frameworks to include all sentient life.

But I suppose that as long as we still treat entire swaths of our own species as lesser beings, any form of cross-species legal inclusion is just an ephemeral dream.

Addendum: as the ever keenly perceptive Andrew Nattan observed on twitter, some would draw the line at responsibility. I.e. if one sentient being such as an orca would kill another – a dolphin for example – if we’re to be truly consistent and inclusive we’d have to convict the orca for murder.

This however leads to a different but related discussion: one about free will and responsibility. Andrew’s argument presumes that all sentient beings have free will, and that they make deliberate decisions whilst fully aware of the consequences.

However this has been proven to be a fallacy. Recent research in neuroscience goes as far as to suggest even human beings don’t have free will – or if we do, it’s of limited scope and influence on our daily actions – which casts the whole debate about sentience, responsibility, and punishment in an entirely different light.