Sentience: the trait that makes us matter

Whether an animal is a dog, lion, chicken, fish or human, we share one thing in common: sentience.

Sentience is the capacity to have a subjective experience of the world. It’s the capacity to experience feelings and sensations.

When we say a being is sentient, that means it feels like something to be that being. Saying a human is sentient means it feels like something to be a human, and saying a salmon is sentient means it feels like something to be a salmon.

Of course, not all experiences of sentience are the same. Being a human undoubtedly feels different than being a salmon. However, it would be unwise to believe like we often do, that one experience is “better” than the other.

Indeed, perhaps because we (or at least some of us) can write poetry, solve quadratic equations, or debate philosophy, we humans like to think that our experience of the world must be “the best”. The richest, broadest, and most meaningful experience of the world.

This may be true in some aspects, but not necessarily in others.

Take the example of perceiving the world through our senses. As it turns out, human senses are embarrassingly dull compared to that of many other animals. Dogs smell better than us, eagles see better than us, and dolphins hear better than us. Could it be that at least in some regard, these animals have a richer experience of the world than us?

And beyond that, many animals perceive the world in ways that are completely foreign to us. Mice use their whiskers to locate food in complete darkness, sharks detect electric fields to hunt in murky waters, bats use echolocation to navigate, and salmon can sense the earth’s magnetic field.

Indeed many animals have abilities that to us are like literal superpowers. No wonder in fiction humans who acquire animal abilities become superheroes, like Spiderman, Wolverine and Black Panther.

On top of that, years of research has now found that many animals can not just sharply perceive the world, but solve problems, feel a wide range of complex emotions, and suffer both physically and psychologically. Tuskfish use tools to crack clams open, chickens get scared when they hear predators, and cows get distressed when separated from their herds.

The mirror test, a test designed to determine whether an animal can recognize themselves in a mirror, has been passed not only by the usual culprits like chimpanzees, elephants and dolphins, but also by magpies, manta rays and bluestreak cleaner wrasses (a tiny fish the length of a smartphone).

Being sentient undoubtedly feels different for different animals. But so long as it feels like something to be them, they are sentient.

They’re not a “something”, they’re a “someone”.

So, why does this matter?

The reason sentience is important is because it forms a solid basis for determining what, or should I say who matters morally.

When a being is sentient, our actions can affect them in a real way. For example, a rooster is sentient, so if I tie one up and throw him in a pond, he will panic, suffocate, and drown. My actions will cause him to suffer (intensely), and that suffering will matter to him. That’s why a rooster matters morally.

In contrast, when an entity isn’t sentient, our actions can’t affect it. For example, rock isn’t sentient, so if I tie one up and throw it in a pond, it will simply sink. It won’t panic, suffocate, or suffer. My actions don't and can’t cause it to experience anything. That’s why a rock doesn’t matter morally.

When an entity is sentient, we should think very carefully about how our actions impact them, while if it isn’t, doing so is inconsequential.

If you’ve ever thought about helping animals, you might’ve thought: “of course we should help dogs, elephants and dolphins, but what about chickens, trout and soldier flies?”

In other words, where do we draw the line?

Intuitively, we tend to use criteria like intelligence, cuteness, or an animal’s status as a “companion animal” to measure an animal’s worth and draw a line. Monkeys matter because they’re smart, foxes matter because they’re cute and cats matter because they're companion animals.

However, this would (and does) lead to treating certain animals as less than others unfairly and irrationally. Dogs for example are smart, cute and “man’s best friend”, so we welcome them into our homes, give them belly rubs and play fetch with them. Chickens on the other hand are considered by many stupid, unsightly and a mere “farm animal”, so we lock them up in barns, kill them and eat their bodies.

In other words, using traits like intelligence, cuteness or status as “companion animal” to measure an animal’s worth leads to discrimination which in the real world has devastating consequences for the unlucky animals who lack those traits.

In contrast, using sentience as the sole criterion for determining if an animal matters allows us to guard against that and be impartial. If sentience is what matters, then dogs and chickens both matter, despite their differences, and we can create a just world for both of them.

No matter what species an animal belongs to, when they are sentient, their experiences, wellbeing and suffering matter to them, which is why they should matter to us.

If our goal is to create a just world for animals, instead of looking for where to draw a line, we’d much better strive to expand our circle of moral consideration to include all sentient beings.

Written by Ryuji Chua and Tosh

Special thanks to Oscar Horta