Since you visited the blog, I'm safely assuming, you, as a member of the homo sapience species and would likely be curious to know where do we stand among our brothers and sisters from different species and kingdoms? You probably wondered what makes us human? Let's break it down. How exactly do we differ from other animals in terms of our genes, brains, hormones, and behavior? And how do we explain the diversity and complexity of human culture, morality, and creativity?
These are some of the questions that Robert Sapolsky, a professor of neurology and neurobiology at Stanford University, tackles in his fascinating lecture series on human behavior which has been lying at the core of my heart for a very long time and had influenced me through several steps of life. Hence in this blog, I will summarize the first part of his lecture, where he compares humans with other animals and shows how biology influences our behavior and cognition. And despite our self-centered ego bias, we aren't being able to distinct ourselves from our primate cousins.
Sapolsky begins his lecture with a joke about his childhood dream of being applauded in a basketball stadium, which he says is the closest he will ever get to that fantasy. He then explains his goal of comparing humans with other animals and challenges the notion that humans are unique in terms of genes, neurons, or neurotransmitters. He says that these are just the building blocks of life, and that what matters is how they are organized and regulated. He gives some examples of how genes can be turned on and off by environmental factors, how neurons can form new connections and prune old ones, and how neurotransmitters can have different effects depending on the context and the receptor.
The Not So Human Part
He then moves on to discuss some examples of animal behavior that challenge human uniqueness. He starts with female hamsters and humans, who synchronize their ovulatory cycles through olfaction. He says that this is not a sign of social bonding, but rather a way of avoiding competition and increasing the chances of fertilization. He then talks about chess players and baboons, who activate the same stress response with different triggers. He says that the stress response is adaptive for short-term threats, but maladaptive for chronic challenges. He then talks about chimps and humans, who kill members of their own species, sometimes in organized ways. He says that this is not a sign of rationality, but rather a result of emotional and social factors. He mentions about chimps and humans, who have theory of mind, which is the ability to infer the mental states of others. He says that this is not a sign of intelligence, but rather a way of manipulating and deceiving others. He adds that only humans have secondary theory of mind, which is the ability to infer what others think about what we think, and that this is the basis of empathy and morality.
He further explores the domains of aggression, empathy, and reward in humans and other animals. He says that humans can be aggressive in ways that are unprecedented, such as drone bombing or passive-aggression. He says that these are not signs of sophistication, but rather of detachment and dissociation. He says that humans can empathize with members of other species, paintings, or imaginary animals. He says that these are not signs of weakness, but rather of imagination and compassion. He says that humans can anticipate and pursue rewards that are not immediate or tangible, such as chess or art. He says that these are not signs of madness, but rather of creativity and curiosity.
He ends his first part of lecture with a cliffhanger, promising to continue in the next part, where he will talk about how humans differ from other animals in terms of dopamine, culture, and morality. And I will do the same. Please stick with me for a moment to unravel the true uniqueness of humanity, discovered by humans.
The Question of Human Uniqueness is not of a kind, but degree.
Sapolsky returns to his lecture with a discussion of dopamine, the neurotransmitter that is involved in reward and motivation. He says that dopamine is not about the pleasure of reward, but rather about the anticipation and uncertainty of reward. Showing an example of a study where monkeys were given juice as a reward for pressing a lever, and their dopamine levels were measured. He explained that the monkeys showed the highest dopamine levels when the reward was 50% probable, meaning that they were most excited when they did not know if they would get the juice or not. He says that this is similar to gambling, where the uncertainty of winning or losing is what drives the dopamine rush.
He then says that humans can sustain dopamine-driven work for long periods of time, even when the reward is not immediate or tangible. He gives an example of chess players, who can spend hours or days playing a game that has no intrinsic value but is driven by the challenge and the possibility of winning. He says that this is similar to art, where the reward is not material, but aesthetic or emotional. He then says that humans can even hold on to rewards that come after death, such as heaven or reincarnation. He says that this is the ultimate form of dopamine, where the reward is infinitely delayed and uncertain, but still motivates people to behave in certain ways.
He then moves on to talk about culture, which he defines as the non-genetic transmission of behavioral styles. He says that culture is not unique to humans, but that humans have the most complex and diverse forms of culture. He gives some examples of how culture varies across different human groups, such as food preferences, clothing styles, music genres, and religious beliefs. He then gives some examples of how culture exists in other animals, such as chimps and baboons.
He says that chimps have regional differences in tool use and social behavior, such as using sticks to fish for termites, or using rocks to crack nuts, or greeting each other with handshakes or kisses. He says that these behaviors are not genetically determined but learned from other chimps in the same group. He then says that baboons can learn to groom each other and reduce aggression, as shown by a study where a group of baboons became more peaceful after the dominant males died of tuberculosis. He says that these behaviors are not innate but influenced by the social environment.
He talks about morality, which he defines as the ability to hold contradictions and impossibilities. He says that morality is not rational, but emotional and intuitive. He gives an example of a study where people were asked to judge moral dilemmas, such as whether it is acceptable to push a fat man off a bridge to save five people on a train track. He says that people’s judgments were not based on logic, but on gut feelings and emotions. He then gives an example of a person who exemplifies morality, Sister Helen Prejean, a Catholic nun who works with death row inmates and advocates for the abolition of the death penalty.
There’s one thing that humans do that no other animal comes close to. It’s when we decide that the more impossible something is, the more we have to make it happen. This isn’t some big fancy things like culture or brain power, but it’s a core part of what makes us human, and you won’t find anything like it in the rest of the animal kingdom. To illustrate this, let me tell you a story about a nun who devoted her life to saving the souls of the most hopeless murderers on death row. She figured that the more doomed they were, the more she had to do something about it, whether it was to redeem them from hell or transform their rotten lives. This kind of behavior makes no sense, and it’s utterly unique. He says that Sister Helen Prejean forgives and loves the most unforgivable and unlovable people to ever walk on earth. And this is not a sign of stupidity, but of grace and compassion. He says that this is the most irrational and magnificent thing humans can do, to love their enemies and to hope for their redemption. He says that this is what makes us human, to be able to hold contradictions and impossibilities, and to act on them.
Sapolsky ends his lecture with a call to action, urging the audience to make a difference in the world despite the impossibility. He says that humans have the potential to be the best or the worst of animals, depending on how they use their biology, their culture, and their morality.
I hope you enjoyed this summary and learned something new about human behavior and cognition. If you want to watch the full video, you can find it here, or read more about Sapolsky’s research and writing here. You can also check out some of his books, such as Behave, Determined, or [A Primate’s Memoir]. In my honest thoughts, Sapolsky is one of the best scientist-writers of our time. He is also one of the most humane and humble scholars, who can inspire you to make a difference in the world. He is, in short, a human being.