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Animals as Persons: Can We Scale Intelligence or Sentience?

An essay in New Scientist called "Almost Human" raises many important questions

A recent essay by Aviva Rutkin called "When is an animal a person? Neuroscience tries to set the rules" focuses on the daunting question, "When is an animal a person?" It's surely an extremely important question and also a "hot" topic, as many people are working on achieving the legal status of "person" for nonhuman animals (animals). For example, attorney Steven Wise and people working with The Nonhuman Rights Project have been working to achieve legal personhood for chimpanzees, and a recent essay by philosopher Mark Rowlands called "Are animals persons?" concludes "personhood is widely distributed through the animal kingdom." More information on the general topic of personhood in other animals can be found here.

Almost human?

The title of Ms. Ritkin's print essay is "Almost human?" and when I saw it I immediately thought about whether it's really possible to scale intelligence or sentience and make comparisons among individuals of different species. Her essay is currently unavailable online, so here are a few snippets to whet your appetite for more.

Concerning Steven Wise's efforts, Ms. Ritkin writes,

... the non-profit Nonhuman Rights Project has drawn attention for its attempts to take legal action to free captive chimps – so far Hercules and Leo from a Long Island research lab and Kiko and Tommy from private ownership. A new documentary, Unlocking the Cage, chronicles the group’s so-far-unsuccessful quest for what its president Stephen Wise describes as 'legal transubstantiation'. If the courts ever find in its favour, 'the non-human animal would come out of that courtroom looking the exact same, but her legal status would be forever changed', Wise said on the film.

Ms. Ritkin also notes,

Public opinion does seem to be shifting toward giving animals at least some rights. Last year, a Gallup poll found that 32 per cent of people in the US believe that animals should receive the same rights as people – an eight-point rise since 2008.

But what rights might those be? The Nonhuman Rights Project focuses on habeas corpus, to protect against unlawful imprisonment. The group wants captive chimps to be sent to a sanctuary, where they can live in a wilder and more open environment. So far, no judge has ruled in favour of their cause. However, in May, it was announced that the chimp research facility where Hercules and Leo live will transfer the pair, along with the 200 others, to a sanctuary.

A checklist for personhood

A most important aspect of Ms. Ritkin's essay is her inclusion of a checklist for personhood. She writes:

Philosophers disagree on exactly what it would take for an animal to qualify as a person. Kristin Andrews at York University in Toronto, Canada, suggests searching for the six attributes listed here.


Showing emotion, perspective and a point of view. Chimps and bonobos throw tantrums when they don’t get their way. One researcher has reported a baboon urinating on a rival as a form of revenge.


The ability to think and reason logically. Elephants, monkeys, birds and even fish have shown some understanding of basic maths. Some animals can handle tougher problems: in one study, orangutans worked out the principles of water displacement to get a peanut. Many animals have also mastered tools: chimpanzees use leaves as toilet paper, for example, and crows make their own hooked tools to forage.


A distinctive, individual character. Individual squid can be shy or bold; sharks may be more social or solitary; and some great tits act cautiously while others are the reverse. Members of some spider species can vary in how docile or aggressive they are. As for chimps, their personalities can be assigned to sit on a six-point scale.


The capacity to form bonds with other creatures, and to care for others and be cared for. Pilot whales stay close to one another as they dive, and use frequent bodily contact, behaviour that looks like it is giving social comfort. Monkeys and elephants grieve the loss of fellow creatures. Imitation, too, could be a sign of the ability to form relationships – newborn chimps can imitate facial expressions, for example.

Narrative self

The sense of having an autobiographically connected past and future. Dolphins can remember tricks they did in the past. Apes have some ability to look forward and backward: by remembering major events from previously watched movies, or taking a tool with them to solve a human-posed puzzle.


The ability to make decisions for oneself. Communication might indicate an animal’s preference – like when an orangutan was observed pantomiming for help with a coconut. Some species also show signs of distinct social cultures; orcas, for example, live in groups with their own lifestyle, social structure and hunting techniques."

Can we truly scale intelligence among species and should intelligence be the defining measure for granting personhood?

" ...the question is not, Can they reason? nor, Can they talk? but, Can they suffer? (Jeremy Bentham)

Two sentences that caught my eye in Ms. Ritkin's essay are: "Instead of giving animals the full upgrade, we could start to understand them as near-persons, or at least as creatures of heightened moral value. We could then bestow rights in proportion to their abilities and intelligence." (my emphasis)

It's clear that humans will be the standard against which other animals will be compared and to which animals will be "upgraded," and I don't see how this exercise will really clear up the matters at hand. And, two questions immediately came to mind, namely, "What is a near-person?" and "What about humans who are near-persons?" I'm not going to ponder these questions here, and I know they have been discussed by philosophers and lawyers with varying points of view.

How does sentience factor in to assessments of personhood? One important point concerns the concentration on intelligence, or sapience, but many people really are concerned with an individual's capacity to experience different emotions, or sentience. Often, when people are concerned with an individual's well-being, they focus on their ability to experience pain. Like Jeremy Bentham and others, I favor using sentience as the guide for granting personhood. However, quite frankly, I have no idea of how sentience or the ability to feel pain can be reliably scaled among individuals of the same or different species.

The difficulties of cross-species comparisons of intelligence and sentience

I consider questions of scale, or of proportion, about intelligence and sentience in two previous essays. In "Are Pigs as Smart as Dogs and Does It Really Matter?" I wrote, "I don’t consider questions comparing the intelligence of different species to be useful because individuals do what they need do to be card-carrying members of their species. Comparing members of the same species might be useful in terms of the ways in which individuals learn social skills or the speed of learning different task, but comparing dogs to cats or dogs to pigs says little of importance." Many researchers agree that cross-species comparisons of intelligence are fraught with error and species are difficult to accurately rank.

In another essay titled "Do 'Smarter' Dogs Really Suffer More than 'Dumber' Mice?" I considered problems in reliably scaling sentience and the possible relationship between intelligence and sentience. I stressed that there is no evidence that supposedly smarter animals suffer more than animals who supposedly are not as intelligent. In this essay I also wrote, "It's also become clear that the word 'intelligence' needs to be considered in light of what an individual needs to do to be a card-carrying member of his or her species and that comparisons between species don't really tell us much. So, asking if a dog is smarter than a cat or a cat is smarter than a mouse doesn't result in answers that are very meaningful. Likewise, asking if dogs suffer more than mice ignores who these animals are and what they have to do to survive and thrive in their own worlds, not in ours or those of other animals."

Individual pain matters

In "Do 'Smarter' Dogs Really Suffer More than 'Dumber' Mice?" I also wrote, "we need to take the pain and suffering of 'less intelligent' animals very seriously and that speciesist arguments about 'higher' and 'lower' animals need to be shelved. I also stressed "The pains of supposedly 'smarter' animals are not morally more significant than the pains of 'dumber beings.' Solid science supports these ideas and I stand by this conclusion." Three years later, I still do.

Along these lines, Dr. Lori Marino, founder of the Kimmela Center for Animal Advocacy, Inc., says it well: "The point is not to rank these animals but to re-educate people about who they are. They are very sophisticated animals."

It's difficult enough for humans to accurately scale pain among humans, and it's more difficult and arrogant to assume we can scale pain for other animals. My pain is my pain, your pain is your pain, dogs' pain is their pain, and mice's pain is their pain. Ranking other individuals of other species in comparison to humans or to other animals, including members of their own species, robs them of their individuality, and also can be all too self-serving for us.

I wish all of the dedicated people working on personhood for nonhuman animals the best of luck. Even when there are failures, these efforts call attention to the fascinating animals with whom we share our magnificent planet. When essays such as Ms. Ritkin's are read by people who have never even imagined that others are working on these sorts of projects, or by people who want to learn more about what is being done, we can only hope they will get on board and support these efforts.

Marc Bekoff's latest books are Jasper's Story: Saving Moon Bears (with Jill Robinson), Ignoring Nature No More: The Case for Compassionate Conservation, Why Dogs Hump and Bees Get Depressed: The Fascinating Science of Animal Intelligence, Emotions, Friendship, and Conservation, Rewilding Our Hearts: Building Pathways of Compassion and Coexistence, and The Jane Effect: Celebrating Jane Goodall (edited with Dale Peterson). The Animals' Agenda: Freedom, Compassion, and Coexistence in the Human Age (with Jessica Pierce) will be published in early 2017. (Homepage:; @MarcBekoff)