Humans and animals divide. What truly sets us apart?

What Makes Us Human? Philosophers’ Theories and Children’s Theories

Humans and animals. Ancient philosophers already pondered the difference between them and what truly makes us human. According to Aristotle, it is the capacity for reasoning and forming social groups. Plato suggested it is the soul striving for truth, goodness, and beauty. Cicero claimed that the essence of humanity lies in language, while Marcus Aurelius believed it was the ability to control one’s own emotions. Heraclitus of Ephesus pointed to something else entirely: the consciousness of one’s own existence.

Interestingly, primary school students reach similar conclusions—though expressed, of course, in different words and contexts. When I asked children gathered at a meeting in a library in Zduńska Wola what distinguishes us from (other) animals, I received these answers:

• We are smarter than animals and have bigger brains.
• We sort garbage, care for the planet and wild animals, but wild animals do not care for us.
• That’s not true. We are worse than animals. We lie and gossip, and animals do not.
• We speak. A dog barks, but that’s not the same.
• We know who we are, and animals do not know who they are.
• Maybe it’s because we wear jewelry?

Actually, all the children were right. But one child was closest to the truth. At least that is what the discoveries and observations of neurobiologists, cognitive scientists, and other contemporary researchers suggest.

Humans and Animals: We Are Smarter and Have Bigger Brains

Homo sapiens—wise man—evolved around 200,000–300,000 years ago, but we were not the first representatives of the genus Homo. Homo habilis, living about 2 million years ago, walked on two legs and probably knew how to use primitive stone tools. Homo erectus was even more manually capable, and additionally, was the first to learn how to use fire. Neanderthals lived alongside Homo sapiens at one point and, according to genetic research, often interbred with us.

For about 30,000 years, however, we have been the only hominid (representative of the genus Homo) living on Earth. Why did we win the fight for leadership on our planet?

The answer is simple: thanks to our brain. This is not about its size (Neanderthals had larger brains than us, and dolphins currently have larger brains), but about the development of regions responsible for cognitive flexibility, imagination, and abstract thinking. Although MRI studies suggest that our brain lacks any structures not present in the brains of our closest cousins, the great apes, we can utilize these structures better. Because we require a lot of energy to do this (our brain constitutes 2 percent of our body weight but consumes as much as 20 percent of energy), we paid a price: the loss of muscle mass. Physically, we are much weaker and frailer than our ancestors.

Empathy Matters: We Care for the Planet

It is true: Homo sapiens is the most capable of self-sacrifice—not only toward members of our own species, but also toward other animals, the planet, and higher values. We are the only species that can boast of morality, a “compass” that tells us what is good and just. This extends beyond just ourselves and our offspring.

Morality results from the development of various brain structures, but mirror neurons deserve special attention—these are nerve cells that allow us to understand what someone else is feeling; to imagine, or even feel, their suffering or joy. The development of these neurons fostered a greater capacity for empathy and compassion in us than in other species, and it played a key role in creating social networks.

Mirror neurons are particularly developed in humans and animals like us, but we are not the only species that possesses them. Apes, elephants, dolphins, rats, and even some birds (parrots and ravens) have similar cells. Empathetic reflexes are also observed beyond humans. Apes, when unfairly given food, are able to share with others. Their capacity for sacrifice even extends beyond their own species. For instance, in 1996, at a zoo in Chicago, a gorilla saved a toddler who had fallen into the enclosure and lost consciousness. She gently picked him up in her large arms and carried him to safety while cradling him.

Humans and Animals: We Lie and Gossip

The boy from Zduńska Wola who claimed we are worse than animals was also unfortunately right. Humanness is distinguished by morality, but it is also distinguished by its exact opposite. Humans are the only species capable of lying, deceit, and highly sophisticated manipulation.

“Lying is a uniquely human thing,” says Thomas Erikson, Swedish author and social communication psychologist, known for global bestsellers like Surrounded by Idiots and Surrounded by Liars. “We all lie. Every day. Probably most often when answering the question, ‘How are you?’ We lie to deceive someone, to gain something, but also to be accepted, liked, or to avoid causing distress to someone.”

It is true that some animals can deceive in their own way—for example, by feigning death when a predator approaches—but only humans can lie with premeditation. Furthermore, lying and manipulation were our evolutionary allies—it was partly thanks to them that social bonds were formed.

Gossip is similar. Ever since humans developed language (for tens of thousands of years), we have been transmitting information about others. This allowed us to share knowledge, warn each other about “bad characters,” and simply provide entertainment. The ability to gossip made the cognitive revolution possible.

Humanness and the Matter of Language: We Speak, and the Dog Barks

Language is a system of abstract signs governed by grammatical rules. Thanks to these rules, we can create an unlimited number of combinations and sentences from a limited number of words. By knowing just a thousand words in a given language, we can express practically anything we want. Even if it is abstract—through creativity, we can create fictional stories.

Other animals also communicate with each other. A large proportion, like humans, use auditory signals. It is true that a dog barks differently out of excitement, differently out of fear, and yet differently when warning its owners that someone is approaching the door. However, it cannot arrange its sounds into sentences governed by the rules of syntax, semantics, and grammar. It uses a signaling system (like many other animals) but not language.

And yet, we cannot be sure that language—as a system of signs from which an unlimited number of messages can be constructed—is exclusive to humans. The “clicks” and “whistles” of dolphins also seem to have their own semantics and arrange themselves into equivalents of human sentences. The problem is that we—at least for now—cannot decipher them. Scientists have observed that the communications of these animals are elaborate and probably created according to “dolphin” grammar, but we do not have the key.

Humans and Animals: We Know Who We Are

Self-awareness. Heraclitus of Ephesus pointed to this as the factor distinguishing us from animals. It is the ability to perceive oneself as a separate entity, which allows us to understand our thoughts and feelings, understand ourselves in the context of not only the present but also the past or future, plan, predict, and build deep relationships with our surroundings and with ourselves.

We are not born with full self-awareness. A newborn does not understand that it is separate from its environment (primarily its mother). In infancy, it will gradually discover its own body (noticing it can move a hand or foot), and then the environment’s reactions to its behavior. We speak of full self-awareness when a child recognizes its own reflection in the mirror (between 18 and 24 months).

The thing is, the “mirror test” is passed by more than just humans. Apes (chimpanzees, orangutans, bonobos, and some gorillas), dolphins, magpies, and elephants also succeed. What is more, the latter are so conscious that they mourn the death of their own species. They stop, almost “in contemplation,” when encountering the remains of other fallen elephants, and when someone from the herd dies, specific mourning rituals are observed.

Experiencing Art: We Wear Jewelry and Dream of a Better World

It is quite possible that the love of art and aesthetic sense constitute our humanness. Leo Tolstoy wrote: “Art is an organ of human life.”

Indeed, it is difficult to find another trait that so strongly differentiates us from animals. While we use language, dolphins likely do too. Furthermore, we have empathy and can care for other species—like gorillas. Similarly, we know who we are and pass the mirror test—like magpies. Finally, although we grieve, elephants probably do too.

But no other species has a fondness for beauty. Although chimpanzees can create simple, colorful paintings (some of which fetch staggering prices at auctions), they are not consumers of art. In other words, while they eagerly dip brushes in paint and smear them on canvas, they lose interest in the painting as soon as they finish their work. It is also never appreciated by other apes.

Art has accompanied humans from the very beginning, and if so, it was likely evolutionarily necessary for our survival. Initially, it primarily served a utilitarian role (cave paintings containing warnings about predators or hunting instructions); over time, it became a carrier of our emotions, experiences, longings, and impressions. Practicing and engaging with art developed our creativity, and with it—cognitive plasticity, which allows us to adapt to new conditions, learn from mistakes, develop, and constantly dream of a better world.

Therefore, despite having a smaller brain than Neanderthals, we probably won the race for the future.

Read the original article in Polish: Ludzie i zwierzęta. Tak bliscy, a tak odmienni