Human Consciousness, Theory of Mind, and Smart Animals

Nim Chimpsky doing the dishes [1]

Human beings are unique to all other creatures in the Earth biome. Is this statement even true? Is this human hubris or a dangerous modern idea that has separated us from Nature to lead to our eventual destruction? Maynard Smith listed human language as the most recent major transition in evolution. [2] Whether consciousness or language in humans came first is an open question. Since writing is very recent, the only ways to track language in the archaeological record are by throat and mouth anatomy, genetics, and artifacts of symbolic thought such as musical instruments, art, and burial of the dead. [3] Of course, symbolic thought is a signal of consciousness, not necessarily language. In genetics, the FoxP2 gene has been studied extensively as implicated in human speech. [4] There are mutations to it that differ from chimps. Recently, however, the consensus is that these mutations occurred before homo sapiens split off from their common ancestor. This means that Neanderthals, for instance, were perhaps capable of speech. [5] Speech is not the only means of language, gesture languages like deaf American Sign Language are real languages and no speech is involved. Language seems to be a separate system with speech just one possible communication device. Whether Neanderthals had language is a hotly debated topic. [6] [7] Homo sapiens and Neanderthals have a common ancestor about a million years ago. [8] Chimps and Bonobos are about the same evolutionary distance apart and recent research is starting to show how different they are cognitively. The study of language evolution is still at a very young stage and whether language is unique and first evolved in modern humans is an unanswered question.

Theory of Mind is the realization that for conscious beings to communicate they must be able to recognize others as likewise conscious beings. This presents sort of a back door to the study of consciousness. In 1978, David Premack and Guy Woodmark published Does the Chimpanzee have a Theory of Mind? They defined it thus:

“In saying that an individual has a theory of mind, we mean that the individual imputes mental states to himself and to others (either to conspecifics or to other species as well).” [9]

Experimental results have been mixed but this has started a vast research project in animal and human cognition including dogs, crows, parrots, fish, squirrels, autistic, and child development. [10] There is even a Theory of Mind in literary theory leading to my favorite research paper title: Do Experimental Scientists have a Theory of Mind? [11] As to the actual research, two ideas have come out about this:

1. Theory of Mind is not a single concept but a cluster of concepts that vary from species to species, during child development, and even among adult humans.
   

2. Animals have specific cognitive abilities because they need them to exist in their particular ecological landscape. Without this, experiments will fail to answer any meaningful questions. For instance, work on chimps was inconclusive until it was realized that the strict social dominance hierarchy of chimp interaction needed to be considered. With Bonobos, who have hierarchies that are looser and different than chimps, chimp-derived experiments either bored them or the competitive nature stressed them out. Experiments had to be designed with their social system in mind. Bonobos and chimps, as our most recent surviving common ancestors, are an important study group as they are only one million years apart and quite different in behavior. Finding what is like and what is different cognitively between them is important but as the table below shows, there is still much research to be done with Bonobos.

[12]

Whether language started with homo sapiens or not, it is now generally excepted that language is unique to humans only. Human language is different in that is endlessly malleable, there is no end to the words that can be created, or to the different ways they can be used. For instance, there is no lower bound to a human sentence, it can go on forever. This malleability is one reason why there are so many human languages. No other creature has this capacity. For instance, birdsong is also complex and constantly evolving. But birdsong is for one purpose, sexual selection, and usually, only males sing. Actual vocal communication uses a much-reduced set of cries. This is also true with mathematics. Many different animal species including birds and fish can count and do simple arithmetic, but only with a limited set of numbers. Humans alone have infinite numbers, humans alone have created mathematics. And humans are the only species I know of who are actively trying to communicate with other species. Stories going back millennia, myths, fables, and fairy tales, all have talking animals in them. When I was a kid there were TV shows of Mr. Ed, the talking horse, and Cleo, the talking Basset Hound. Perhaps this is our own Theory of Mind projecting itself on other animals.

Clever Hans

{13}

In 1904, after four years of training, Wilhelm von Osten, a high school mathematics teacher, started touring Germany giving free demonstrations of his incredible horse, Clever Hans. The horse knew numbers and the alphabet and he could spell out by tapping his foot, words, whole sentences, and the answers to arithmetic problems. Hans could look at a painting and spell out the name of the artist, he could listen to a symphony and name the composer, he could add, subtract, multiply and divide numbers, reduce fractions and take square roots. He could also solve algebra problems! How was he doing this? The German board of Education set up a commission to study this phenomenon. After a year and a half, they came to the conclusion that Hans was for real. Finally, in 1907, Professor Oscar Pfungst solved the mystery. Clever Hans was reading subtle changes in von Osten’s body language, like a master poker player reading another player's tells.’ When Hans couldn’t see von Osten or von Osten didn’t know the answer to the question, then Hans failed to get the correct answer. This incident sort of started experimental psychology and the Clever Hans Effect is something to be avoided in any experimental design. It must be noted that what Hans was doing was a major cognitive feat that no one realized horses were capable of, it just didn’t have anything to do with human language or human-like intelligence. In 1910 von Osten died and in 1914 Clever Hans was drafted into the German army. Sadly, he was one of the 8 million horses that perished during World War I. [14] [15] [16] [17] [18]

Doctor Dolittle

[19]

Dr. Dolittle started with the British soldier, Hugh Lofting, writing home to his children from the trenches of World War I. Lofting emigrated to America after the war and in 1920 The Story of Doctor Dolittle was published. Dr. Dolittle had discovered the language of the animals and with his talking animal companions they traveled the world talking to different species about their habits and lives. There were twelve Dr. Dolittle books published including two published after Lofting’s death in 1947. [20] [21] During the summer of 1957, when I was eight years old, I discovered the fantasy and science fiction section of the South Euclid public library. By the end of the year, I had read every single book in that section starting with all twelve of the Dr. Dolittle series.

American Behaviorism

[22]

Behaviorist theory dominated American psychology from the start of the 20th century and lasted almost until BF Skinner’s death in 1990. Behaviorism rejected all ideas of consciousness stating that all behaviors (animal or human) are learned reflexes, learned from the environment or from others. Starting in 1937, BF Skinner laid out a theory of learning called “operant conditioning” in which animals and humans learn by a series of positive and negative rewards and punishments. Skinner went on to espouse a philosophy and a way to change human society using behaviorism. By the mid-1960’s he was very popular and one of the most famous scientists in America. [23] In 1959 Noam Chomsky published a critique of behaviorism which would start the science of cognition. [24] This would eventually supersede behaviorism. Today operant conditioning is considered a real but relatively minor part of behavioral learning. [25]

In 1969 I took an Abnormal Psychology course at Marietta College in Marietta, Ohio. The professor was a confirmed behaviorist. Part of the course was a tour of the mental health facilities of southern Ohio. These were still the original 19th-century madhouses with practices not much changed. On one trip we met an 80-year-old woman who had been incarcerated since she was 3 months old. Her mother was originally there and her child had nothing wrong with her mentally except being raised as a crazy person. The people there were trying to “cure” her using operant conditioning. They made her stand up, then she opened her mouth and they used a Pez dispenser to pop a Pez in her mouth. Then she flopped down. They did this again, and again, and again. Just one of the disturbing things I saw during these field trips. We had a little dog named Larry, a cockapoo we found abandoned in a campground in Florida. Larry had the run of the campus and much of the town. That fall, that same professor arranged for BF Skinner to speak at the college. It was to take place in a church because of the large potential crowds. We had talked about going to the lecture but were unable to go at the last minute. People who attended told me that Larry had wandered in, sat in the center aisle, listened for a few minutes, yawned, and walked out. The joke was that behaviorism had bored Larry. How he found this church which was several blocks from the campus and why he went in is one of the mysteries of animal cognition.

It should be noted that of the seven great ape studies listed below, all but one of them were done by behaviorists. Money for these studies dried up in the 1980s and today most of them would be considered unethical.

Donald the Infant and Gua the Chimp

[26]

In 1937, a married couple who were both psychologists took in a female baby chimp, Gua, to raise as a human child with their own infant, Donald. This lasted fourteen months. The purpose of the experiment was to study the behavioral differences between the human and the chimp, given the same structured environment. Their conclusion was that at that age, the chimp was developing faster than the child. One of the four movies they made survives online. [27] It is frankly kind of creepy, the random experiments both were put through. In one scene a gun was shot off directly behind the children’s heads. I don’t have a primary source on the following but supposedly one of the reasons the experiment concluded after fourteen months was that Donald had started acting like his sister, scampering around on the floor on all fours and biting people. Gua was sent back to wherever she came from and died a year later. Donald lived to 43 when he committed suicide. [28] [29]

Viki the Chimp

[30]

In 1947 Viki was taken as an infant and raised by a human couple, again both psychologists. There was no human sibling and the purpose of this experiment was to teach Viki to talk like a human. Viki learned only four simple words: “mama”, “papa”, “cup”, and “up” which she could barely pronounce. It was later learned that the chimp larynx and vocal cords are incapable of human-like speech. Like Gua, Viki died soon after leaving her human family. [31]

[32]

Washoe the Chimp

[33]

Washoe was the first chimpanzee to be taught human sign language using operant conditioning. She supposedly learned 200 signs and taught her adopted son, Loulis, how to sign also. She died in 2007. [34]

Koko the Gorilla

[35]

Koko is a lowland gorilla and was taught ASL by the psychologist Francine Patterson, starting in 1972. Patterson founded the Gorilla Foundation [36] soon afterward to raise money for Koko's and others' care and training. She supposedly learned 1,000 words and could understand human speech. Koko became famous for her interactions with human celebrities like Robin Williams and Capt. Kirk and for her adopting kittens! Before her death in 2018 she supposedly made a final plea for humans to “Save the earth!” The Gorilla Foundation went through several scandals over fundraising for projects that never happen, human staff working conditions, and care of the apes. [37] Koko lived in a trailer, watched television all day long, and became grossly fat eating human food. The American Dream! Patterson never publicly released any of her raw data on Koko, micromanaged her conversations for release, and the “last words” video had been heavily cut. [38] This video in fact appeared among the garbage on my Facebook page just last month. [39]

Chantek the Orangutan

[40]

Chantek was trained by psychologist Lyn Miles at the University of Tennessee. He learned 150 signs and supposedly could recognize himself in a mirror, a cognitive test for self-awareness. Chantek spent his time at the Atlanta Zoo. He died in 2017. [41] [42]

Nim Chimpsky the Chimp

[43]

Nim Chimpsky was of course named after Noam Chomsky, the foe of behaviorism, and who had proposed that language was a strictly human condition. Psychologist Herbert Terrace of Columbia University brought Nim into his home in 1974 to be raised as a human infant and then moved the project to a lab at Columbia University. Nim learned 125 words but Terrace wanted to know if he was actually learning language by studying his data and what data he could obtain from the other Great Ape projects. In 1979 he published his results [44] in which he concluded that no, there was no language acquisition by these apes. For one thing, operant conditioning with its is really a triumph for science over all the woo surrounding these studies. Nim, however, had a more tragic fate. Adult male chimps are aggressive, violent, and can be quite dangerous. They also live together in strict hierarchies. Nim was introduced to a captive troop but was rejected. He spent a few years in a medical research facility. Nice reward that. He was put in a mixed human environment but killed a poodle. He ended up alone in a cage. Nim died young in 2000. [45] [46] [47]

There are problems with teaching ASL to apes. Ape “hands” don’t have the dexterity that human hands have, so many ASL signs are impossible for apes. ASL is a real human language but it was only first proposed as such by William C. Stokoe in 1965. [48] These researchers didn’t “speak” ASL, maybe didn’t even realize it was a real language at the time, and hired ASL speaking deaf that they couldn’t really communicate with. A case in point is that Koko wrote a poem. Translated by Patterson it rhymed. However, ASL has poetry but it is in the commonality of gestures and the gestures that Koko performed didn’t “rhyme.” So how did Koko know she was signing English rhyme?

Kanzi the Bonobo

[49]

Kanzi is an exception to the great ape studies in that he learned to point out lexigrams (symbols) on tiles instead of ASL and he wasn’t trained using operant conditioning. He also learned himself. They were originally training his mother but he picked it up and became the star. The project was started in the early 1980s by psychologist Susan Savage-Rumbaugh at Georgia State University. She started a foundation like Patterson with Koko. Kanzi supposedly knows 400 symbols and understands English. He also made music with Peter Gabriel and Paul McCarthy and hangs out with Oprah. Whether his success came from being a Bonobo, the training method, or using lexigrams, has been lost in all the fame surrounding him. Savage-Rumbaugh’s foundation came under much the same criticism as Patterson’s ]50] and Kanzi was moved to a Bonobo reserve in Iowa where he was put on a Bonobo diet and supposedly lost 50 lbs. I believe he is still alive today. [51] [52]

Alex the Parrot

[53]

Parrots and some other birds have the vocal apparatus to mimic human speech. When I was a kid the family across the street had a talking bird and when they were away the bird used to scream “Shit!” in the exact voice of the mom. For hours and hours.

Alex started his training in 1976 from Harvard grad Irene Pepperberg, then at the University of Arizona. This went on continuously until Alex’s death in 2007. The project is still ongoing and is now at Harvard. Alex learned 100 words and could count and add and subtract up to eight. One loose measure of animal intelligence is a high brain-to-body size ratio. It is highest in birds like Corvids (crows) and parrots, both of which have been found to have considerable cognitive skills. Pepperberg does not say that parrots can acquire language but that they can use it to communicate with humans and are not just “parroting” the words. [54]

Bunny the dog

[55]

Dogs are believed to be the first species domesticated by man and have been our companions for tens of thousands of years. Dogs are pretty much dependent on humans and it is in their genetic interest to communicate with humans the best they can. Dog cognition study is fairly recent. Wolves, the ancestors of dogs, have larger brains and different cognitive needs but no comparative study exists that I know of between wolves and dogs. Dogs come in many different breeds and I’m sure some breeds are more intelligent than others. I’ve found poodle mixes to be unusually intelligent, once having a cockapoo, as I’ve mentioned before.

In 2019, Alexis Devine, an artist/designer in Tacoma, Washington got a sheepadoodle (Poodle Sheepdog mix) female puppy she named Bunny and started training her on a soundboard, an augmented communication device. She started posting her results on TikTok and now has 5 million followers. [56] What started as a pandemic project now is major research with 6 streaming cameras in her living room gathering data on Bunny’s every move. The soundboard was developed by an organization called FluentPet. [57] It consists of large buttons that the pet steps on that emit a human word. Each button has a lexigram on it and the buttons are arranged on linked hexagonal pads according to speech parts. The buttons and pads are colored according to what we know about dog vision .

[58]

FluentPet is part of a larger research group on animal cognition led by Federico Rossanoand Leo Trottier of the University of California, San Diego. The project, called They Can Talk, [59] started after the success of speech pathologist Christina Hunger with her dog Stella, [60] using an augmented communication device that she used to help pre-verbal children with their speech development.

Bunny is too cute and of course, she is not really learning a language, yet something in the interaction is definitely going on here. One session with Bunny being very confused about who was a dog and who was a human was particularly weird. Bunny is communicating with Devine, this looks certain. Dog hearing is also different than humans and of course, a dog’s sense of smell is legendary. How dogs communicate among themselves is still pretty much unknown, [61] but they do communicate acoustically. I don’t know if the button uses digital sound but I found something interesting. Sounds and complex pictures are compressed when they are digitized. The compression is called perceptual compression because it is compressed with particular emphasis on how humans hear and see. I wonder what a human voice sounds like compressed to dog hearing? To me, Bunny and others represent a very exciting development. [62]

Billi the Cat

[63]

No one thought that a cat could learn to communicate on a soundboard but Billi came through. She is a very domesticated cat, walking on a leash, for instance. Her claim to fame is hitting the “Mad” button over and over. [64] She also uses the device to communicate. It will be interesting to see these animals in a few years. I hope that at least one makes it on Oprah.

So where are we? Language is still considered unique to humans but whether it is unique to our human species is still an open question. So is the evolution of language. Animals can communicate using methods we are just beginning to understand and wild and especially domesticated animals can communicate with humans. How this relates to human language and the evolutionary path from animal communication to human language is an open question. I don’t like the words 'language' or even "talking" used when speaking of nonhumans. Communication, yes. Animals of all different types have amazing cognitive skills but what human consciousness is and how it evolved is still just on the edge of speculation. Theory of Mind, being a useful and necessary cognitive process for human consciousness, gets us in trouble because we tend to erroneously assign theory of mind to any species we are in contact with. Recent breakthroughs in how we communicate with domestic pets open up whole new possibilities in our relationships to them.

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62. Adrienne Matei, “Bored? These Americans Are Teaching Their Dogs to Talk,” The Guardian, December 8, 2020, sec. Life and style, https://www.theguardian.com/lifeandstyle/2020/dec/08/teaching-dogs-to-talk-stella-bunny.
    

63. “Billi the Cat Can’t Stop ‘Saying’ Mad in This Amusing Video. Watch,” Hindustan Times, July 5, 2020, https://www.hindustantimes.com/it-s-viral/billi-the-cat-can-t-stop-saying-mad-in-this-amusing-video-watch/story-sghGT7VqUKMLiBFEY1m9JN.html.
    

64. Billi Speaks, “Mad” A Short Film Starring Billi the Cat, 2020, https://www.youtube.com/watch?v=xZW2RVY0sWs.