Survival Contingencies: A Review of Sapiens: A Brief History of Humankind by Yuval Noah Harari

My wife and I were traveling from Philadelphia to the Green Mountains of Vermont for a holiday snowboarding trip, when she kindly but firmly suggested that I needed to expand my reading selections. As a junior faculty member, all of the texts I recently selected were either journal articles or books rooted in behavior analysis. I agreed, and we settled upon the audiobook version of the New York Times bestseller, Sapiens: A Brief History of Humankind by Yuval Noah Harari as accompaniment for our journey. As we idled in New Jersey traffic, drove past New York skyscrapers, through Connecticut suburbs, through western Massachusetts, and finally to Vermont, we listened keenly. Although point after point was made, I repeatedly emitted subvocal tacts that are repeated here for the benefit, and perhaps enjoyment, of the behavioral community about this provocative narrative that illustrates the survival of our species, homo sapiens.

Just as the environment selects the operant behavior of individual organisms, so also does the environment select the practices of a group as part of its culture (Skinner, 1981). To the radical behaviorist, cultural practices are behavior patterns of broad similarity, often resulting from similarities in environments.

As B. F. Skinner (1981) noted in “Selection by Consequences,” “Like astronomer and cosmologist, the historian proceeds only by reconstructing what may have happened rather than by reviewing recorded facts” (p. 501). Yuval Noah Harari, reconstructed what may have happened to homo sapiens by describing ever-changing macrocontingencies of homo sapiens that propelled the species from the lower end to the top of the food chain. He draws on knowledge from history, anthropology, and evolutionary biology. Although he does not directly mention the field of behavior analysis (vs. Schneider, 2012), he repeatedly describes environmental contingencies that contributed to the survival of homo sapiens. Throughout his book, Harari draws on historical descriptions from the ontogenic, phylogenic, and most commonly the cultural level of selection.

The evolution of cultural complexity is enabled by the roles operant behavior plays in the ontogeny of individual repertoires and also in the evolution of cultural phenomena. Culturobehavioral lineages are considered the link between behavioral and cultural processes. A distinction between operant lineages and culturobehavioral lineages rests on the fact that operant lineages are the parts of the repertoires of individual organisms and they cease to exist when their host organism dies whereas culturobehavioral lineages endure within populations of individuals (Glenn, 2003). A culturobehavioral lineage exists if the operant lineages of any participants’ repertoires continue by being replicated in the repertoires of other participants.

Harari takes a long running start introducing his evolutionary-derived account, by briefly describing the history of the universe. He mentions the occurrence of the Big Bang, 13.5 billion years ago, that evolved into the amalgamation of matter and energy that formed intricate structures called atoms that combined into molecules around 300,000 years after the Big Bang. He accurately tacts this story as chemistry. He then notes the creation of earth 3.8 billion years ago and since that time certain molecules combined to form large, intricate structures called organisms—he tacts this story of biology. Harari then makes a transition into the story of homo sapiens and reports that around 70,000 years ago this species began to form even more elaborate structures called cultures.

Charles Darwin shared his account of natural selection with us, homo sapiens, in his book On the Origin of Species (Darwin, 1859) and since then behavior analysts have adopted this pragmatist and selectionist account of the world that fits with the theory of evolutionary biology (Baum, 2001; Moxley, 2001), although Killeen (2017) argues a non-Darwinian process provides a more accurate model for most cultural evolution than does selection by consequences. Sapiens: A Brief History of Humankind is organized by three revolutions that shaped the course of history: (1) the Cognitive Revolution, beginning around 70,000 years ago; (2) the Agricultural Revolution, beginning around 12,000 years ago; and (3) the Scientific Revolution, beginning around 500 years ago and continuing into present day. Harari further predicts this last revolution may well interrupt that story and start something entirely different.

The Cognitive Revolution

Harari suggests that during the Cognitive Revolution, homos started out similar to other animals, low on the food chain, foraging for plants, small insects/animals, and occasionally hunting larger game.1 Foraging encompasses tactics used to obtain nonproduced materials or resources often involving hunting, trapping, netting, snaring, gathering, or other techniques (Winterhalder, 1981). Harari writes that the behavior that began to set us apart from other species was our unique language capabilities and how we were able to develop and describe events, including events that are not real. Homos, referring to the genus, ascended to the top of the food chain through flexible mass cooperation, which allowed large numbers of strangers to work together. Baum, Richerson, Efferson, and Paciotti (2004) investigated verbal traditions passed on from generations empirically. They found that the stronger the dependence between choice and earnings, the stronger the verbal tradition. Participants developed choice traditions that resulted in maximizing their earnings. We use language more extensively than other species to shape social structures and relationships. Furthermore, Harari notes that our language is extremely flexible and can be combined in infinite ways to deliver complex nuances and rich information about our world, which is a description aligned with the behavioral community (Hayes, Barnes-Holmes, & Roche, 2001).

In contrast to radical behaviorism, Harari proposes that modern systems and institutions are built on imagined realties created by homo sapiens that contribute to our survival. This point is explained by describing an example of the Peugeot lion, the hood ornament of one of the oldest and largest European carmakers. Peugeot began as a small family business in the village of Valentigney, France. In 2008, Peugeot produced more than 1.5 million automobiles and earned revenues around US$55 billion. Today, Peugeot employs around 200,000 people worldwide, most of whom are complete strangers to one another. Based upon this intriguing statistic, a behavior analyst might ask, what contingencies are attributed to the survival of this culture we call Peugeot? Harari asks a different question: to what extent can we say that the company Peugeot SA exists?

There are many vehicles, but Harari notes these are not the company. Even if every Peugeot in the world were simultaneously junked and sold for scrap metal, Peugeot SA would not disappear. Peugeot would continue to manufacture new cars and issue their annual report. The company owns factories, machinery, and showrooms, and employs mechanics, accounts, and secretaries, but all these together do not comprise Peugeot. Furthermore, a disaster might kill every single one of Peugeots employees, and go on to destroy all of its assembly lines and executive offices: nevertheless, even then the company could borrow money, hire new employees, build new factories, and buy new machinery. Managers and shareholders do not constitute as the company. All managers could be dismissed, and all shareholders could sell their shares, but the company would remain intact. Harari concludes this example by stating that Peugeot appears to have no essential connection to the physical world, so does it really exist? In The Nature of Cultural Things (Harris, 1964), Harris classifies this as a permaclone.

Peugeot, along with Boeing, Amazon, and Google are figments of our collective imagination, tacted as “legal fiction” by lawyers, he claims.2 Like homo sapiens, each company is bound to the laws of the country in which it operates. Both can open a bank account, own property, and pay taxes. Legal fictions can be sued and prosecuted separately from the people who own or work for it. The specific legal fiction that Peugeot, Boeing, Amazon, and Google belong to are considered incorporations or limited liability companies and the author reasons that the patterns of homo sapiens’ behavior resulting from legal fictions are among homo sapiens’ most ingenious inventions.

As intriguing and provocative as Harari’s initial example is, regarding the existence of the company, Peugeot, behavior analysts would ask alternatively: what contingencies allowed Peugeot to, not only survive, but thrive? We may never know the answer, but a behaviorally based conceptual analysis of the phenomenon calls for us to examine interlocking behavioral contingencies (Glenn, 1988). Imagine, during the time of the inception of Peugeot, two family members in the village of Valentigney began creating automobiles separately and soon recognized the demand for their new products. They may have worked together to create more vehicles together than they would have individually, resulting in more reinforcers (e.g., money, family praise, necessities for survival) then if they continued to work in isolation. This pattern continued and as more and more family members and community members became involve, more interlocking behavioral contingencies resulted in greater amounts of reinforcement for everyone involved. As a result the company, Peugeot SA, based upon initial interlocking behavioral contingencies, had been formed. We may call this a culture, even though Harari calls humanities greatest achievements imagined realities, such as companies, religion, democracy, and the United States—let us not forget about the operant contingencies in culturobehavioral lineages, and that these imagined realities or patterns of behavior that fall within what we would classify as a company, religion, or democracy are maintained by contingencies.

Harari also describes the life of a hunter-gatherer during the Cognitive Revolution, noting how these foragers lived a nomadic lifestyle, often traveling in small, intimate groups. They consumed a wide range of foods that included berries, roots, termites, rabbits, and bison, and worked 30–35 hours a week gathering, hunting, preparing foods, and making tools. Not a bad life, he notes. Harari goes on to label the hunter-gatherers as the first affluent class citing their flexibility in work schedule and balanced diets.

Also during the time of the cognitive revolution (about 45,000 years ago), the species homo sapiens began to migrate to other continents bringing drastic changes to the new habitats where they settled. Harari focuses on the example provided by the exodus from the Afro-Asian landmass to Australia. Within a few thousand years of the arrival of homo sapiens, 23 of 24 species of large animals became extinct. Within 2,000 years of our arrival in the Americas, we brought extinction to 34 out of 47 of large mammals in North Americas and 50 out of 60 large mammals in South America. Two general theories for these mass extinctions are discussed. First, the introduction of fire during the cognitive revolution. Homo sapiens were now able to destroy large stretches of ecology and as we changed the vegetation and food sources, some animals thrived whereas others died out. Second, these large animals and predators bred slowly, and they couldn’t evolve fast enough to evade the threat from homo sapiens, nor replenish their numbers as quickly as we killed them.

Glenn (2003) mentions that a necessary element for the origin of culture is the replication of operant behavior across successive individual(s) repertoires in which earlier learners’ behavior functions as part of the environment of later learners. And although individual’s operant behavior is functionally independent of others’ operant behavior, the cumulative effects relate to the survival of the species (Glenn, 1989), whether homo sapiens or not. The relationships between independently evolving operant lineages or cultural lineages and their cumulative effect have been identified as macrocontingencies. Perhaps Harari’s description of the large-scale mammal extinction is a cumulative effect, directly related to the survival of homo sapiens, namely macrocontingencies related to fire, hunting, and other operant behavior.

Harari emphasizes that even early in the cognitive revolution, homo sapiens were causing destruction to fellow species and the landscape. Seventy thousand years later the account of behavioral systems science prompts us to ask the question, has much changed (Mattaini & Aspholm, 2016)?

The Agricultural Revolution

Around 10,000 years ago, homo sapiens largely abandoned their hunter-gatherer behavioral patterns such as foraging and began farming, which resulted in the Agricultural Revolution. Harari notes that farming supposedly provided homo sapiens with a better life; however, he paradoxically identifies the Agricultural Revolution as one of the most prodigious frauds in history. He notes that the average farmer worked harder than the average forager and received a worse diet in return. Interlocking behavioral contingencies resulted in cultural shifts, from foraging to farming—a byproduct of inept decision making. During the Agricultural Revolution, immediate reinforcers of filling a few stomachs and gaining a little security by forming villages, led to forcing many homo sapiens to spend their days carrying water buckets under a scorching sun.

During the Agricultural Revolution farmers grew a limited range of crops—mostly wheat, maize, potatoes, and barley due to a largescale likely return and little response effort. As a result, homo sapiens became malnourished. In addition, the Agricultural Revolution also led to the inception of domesticating animals. The most aggressive animals were culled whereas the fat, submissive ones were bred. During the years of the Agricultural Revolution, chicken, sheep, pigs, and cows multiplied, but lived miserable lives. The males were often castrated or mutilated to make them more manageable, females were repeatedly impregnated, and most were kept in small spaces for short durations before being killed. Making note of contingencies, Harari proposes likely reinforcers that may have maintained homo sapiens’ destructive behavior during this revolution. Farming and domestication allowed humans to multiply exponentially resulting in more land being farmed and more animals being domesticated. This pattern resulted in more babies being born, more mouths to feed, increasing the population that resulted in villages plagued with unsanitary conditions. The consequent rise of agriculture among these place-dependent populations may have given rise to organization of behavior in increasingly complex arrangements of interlocking behavioral contingencies and eventually metacontingcies (Glenn, 1988). As a result, new generations grew up without the knowledge of foraging and gradually it became impossible to turn back the clock.

Perhaps the Agricultural Revolution was a result of misplaced precision. Precise behavior, in the form of farming and domesticating animals, resulted in needlessly effortful and costly outcomes for homo sapiens. Hineline (2005) explains that misplaced precision can be dysfunctional when precision is not essential and that variability should be allowed and, in some cases, perhaps during the agricultural revolution, encouraged. Simon (1983) provides us with an account of choice behavior as it relates to evolutionary theory, and notes that evolution needs variation and selection. Possibly a contributing factor to homo sapiens transition from foraging to farming and domestication is that homo sapiens were not striving for a stationary maximizing state (in foraging), but rather constant movement (resulting in the Agriculture Revolution), local adaptions (producing more crops and domesticating more animals), and acceptable solutions to myopic problems (Simon, 1959).

The hyperbolic discounting model (Green & Estle, 2003; Hantula & Bryant, 2005; Madden, Francisco, Brewer, & Stein, 2011) offers a model that species prefer things (items, solutions, reinforcement) sooner rather than later, but also captures time-inconsistencies and preference reversals. The rate of discounting is not constant over time and species tend to be more impatient in the short run, resulting in a higher discount rate, and more patient in the long run, resulting in a lower discount rate. The hyperbolic discount model has served to be a strong predictor of aggregated homo sapiens choice behavior (Furrebøe & Sandaker, 2017; Wilkinson & Klaes, 2012). Perhaps, the hyperbolic discount model explains patterns of behavior exhibited during the Agricultural Revolution—homo sapiens may have emitted behavior resulting in temporally contiguous, rich schedules of reinforcement by farming and domesticating animals, which resulted in full stomachs for everyone quicker. As opposed to hunter-gatherer tactics, which may have resulted in many failed attempts to secure meals (thin schedule) and temporally extended reinforcement. This model may offer us insight about the precise behavior displayed during the Agriculture Revolution that restricted homo sapiens from optimizing reinforcement contingencies but allowed for the species’ survival.

The Scientific Revolution

Harari proposes that since the Scientific Revolution, homo sapiens decided to discard ignorance and seek out information about the universe. Harari describes this as a massive leap; homo sapiens had finally admitted that we do not know everything and that we can be proven wrong. The species began to link environmental observations and mathematical tools into comprehensive theories that were then tested and applied. Discoveries and solutions to largescale problems were being answered through science inquiry rather than relying on faith. Illustrating this, Harari mentions that lightening was believed to be a sign of God’s wrath, until Benjamin Franklin disproved the theory with lightning rods. Malnutrition, disease, and death were problems to be solved scientifically rather than left to the will of God.

Along with the advancement of science, empires rose. During the Chinese Ming dynasty, Admiral Zheng led sea expeditions with ship fleets hundreds of times larger than Columbus’s fleets, but did not try to conquer other countries. Rather, science drove the exploration and the ability to assist pro-Chinese rulers. Unlike the Chinese Ming dynasty, European imperialists used science to reach new territories, gain profits, and to argue theories that the Aryans were a superior race and were meant to dominate inferior races. This helped legitimize European conquests that enabled rule over populations far larger than their own. In addition, the proliferation of capitalism became ubiquitous during the scientific revolution. Capitalism was highly regarded throughout the Scientific Revolution because wealth earned was reinvested in productive activities resulting in even more wealth. Diamond (1999) offers a similar account, noting the proliferation of cultural wealth largely due to environmental differences between cultures. With more products and services produced, more buyers were, and still are, needed: these marketing tactics have led us into an age of consumerism.

According to Harari, our imagined systems (corporations, religion, laws) were made possible due to homo sapiens’ ability to pass along these ideas. These imagined systems were passed along through numbers and writing. Harari notes that for millions of years homo sapiens stored information in their brains; however, he writes: “unfortunately, the human brain is not a good storage device for empire-sized databases.” He goes on to explain three primary reasons why: (a) although some homo sapiens have extraordinary memories, there is still a limit to which a master mnemonists can recall; (b) homo sapiens die and their brain dies with them; and (c) the human brain has been adapted to store and recall particular types of information (e.g., yellow wrinkles on a mushroom that others reported as poisonous). Writing allowed homo sapiens to pass along an immense amount of data. Over time, homo sapiens were compelled to file and retrieve this data. Ultimately, according to Harari, the persistent nature of filing and retrieving large sums of data resulted in bureaucratic and compartmentalized logic. And today homo sapiens rely on computers, and cloud space to store, process, and retrieve this data.

Harari further addresses the role of money throughout history. To begin, Harari describes that hunter-gatherers and early farming communities transacted and survived by bartering for their goods. As time passed, bartering for goods became considerably more complex as more and more goods were involved. Money became the solution and allowed the sellers to price their goods using a sole currency and convert “anything into anything else.” Homo sapiens started with currencies that held value like barley, gold, and silver. Overtime, as our trust in money strengthened, we moved to a single currency with no direct value and this has evolved into today’s form of money—an electronic currency with no physical existence. According to Harari, money is an “inter-subjective reality” and he uses this term to explicate that money only has value because we trust others to accept it in exchange for our wants and needs. Money has enabled strangers and even enemies to cooperate notwithstanding that it has also diluted human relations and values. To illustrate this, he provides the example of a starving parents selling their children to slavery and our loss in trust in others when they no longer are wealthy. Harari also highlights that money has also held a principal role in homo sapiens’ consumption of goods—consumerism.

Homo sapiens tend to consume more and more items that appear to be unnecessary. Harari describes the cycle of consumerism using the example of obesity. He writes that, “obesity is great for business!” Homo sapiens spend money on food, then they buy gym memberships to lose weight and medications to both lose weight and treat diseases resulting in additional food purchases. Rafacz (2019) offers guidelines for behavior analysts to effectively address widespread unhealthy eating habits using discounting. Outcomes of the consumerism culture have led to excessive and growing consumption, exacerbated by a growing world population resulting in issues of sustainability (Nevin, 2005; Skinner, 1987). Harari again laments that it is too late to turn back now.

In today’s era religion is often considered a source of “discrimination, disagreement, and disunion,” according to Harari, religion should be considered the third unifier behind empires and money. As homo sapiens started to farm, the farmers wanted control over their animals and as a result theism or belief in gods emerged. The famers who wanted control over their livestock treated gods as mediators and sacrificed animals in return for a plentiful harvest. Harari offers a description about the evolution of animism, which evolved into polytheism, monotheism, and dualism. He concludes that the most ubiquitous religion of today’s era is syncretism, which is an amalgamation of ideas and practices from various religions and sources. According to Harari, it is notable that monotheists concurrently embrace and accept capitalism, liberalism, etc.

In summary, Harari writes that homo sapiens have undoubtedly transformed planet Earth and human cultures exponentially in a short time period and with each revolution we have become more powerful. Scientific progress, referred to as intelligent design by Harari, has been made in biological engineering, cyber engineering, and inorganic lifeforms likely to affect homo sapiens’ evolution and could possibly bring an end to our species. Dawkins (1976) would call these cultural revolutions memes. According to Harari, we have reduced famines, cured diseases, and prolonged our survival all at the expense of earth and other species (Chance & Heward, 2010). As a result, according to Harari, we are now in one of the most peaceful eras in the history of homo sapiens. In most parts of the world people go to sleep without fearing a neighboring tribe will infiltrate and slaughter the entire community. International wars have become rare after 1945, largely thanks to the advancement and new threat of nuclear annihilation.

Nevertheless, even with substantial progress (good or bad) the hypothetical question is offered, “has all of this progress brought us greater happiness” or has the collective evolutionary success of homo sapiens resulted in greater suffering to ourselves and other species? Throughout the entire book, until this question is asked, Harari provides a historical account aligned with selectionism and empiricism, highlighting contingencies that resulted in the survival of homo sapiens. Harari chronicles the evolutionary account of homo sapiens by describing behavioral patterns that align within three levels of selection (Skinner, 1981). Whereas Harari poses the mentalistic question: “Are we happier?,” behavior analysts might ask: “Are we reinforced for what we do?”

Tourinho, Borba, Vichi, and Leite (2011) provide us with a behavioral description of happiness using an example of being hired for a new job. An adult may shout, evoked by the announcement of being hired, gifts may be purchased for family members, self-descriptions of happiness occasioned by social stimuli or bodily condition, or even cancellation of prescriptions for antidepressants may occur. Tourinho et al. highlights that we all have idiosyncratic environmental histories and the behavioral patterns that define happiness vary from person to person.

Are we asking the proper question? Would it better to ask how we can save the world with the science we have in front of us? Dixon, Belisle, Rehfeldt, and Root (2018) explain that we can make a large-scale impact to address the present problems of the world caused by verbally sophisticated homo sapiens by concentrating translational behavior analytic research, in particular using derived stimulus relational accounts, to address large-scale problems. Harari offers us a copious number of candid examples about our species survival, but also highlighted that homo sapiens were, and still are, the deadliest species in the history of the world causing destruction to both ourselves, the environment, and other species. So rather than concentrating our efforts on homo sapiens’ happiness as Harari does, shouldn’t we concentrate our efforts on saving the world (Skinner, 1987)?

Sapiens: A Brief History of Humankind, offers us a provocative historical account that highlights the survival contingencies of homo sapiens. Harari, earning his PhD in history from the University of Oxford, and professor at the Hebrew University in Jerusalem, provides us with a well-written book that may be enjoyed by the behavioral community. He writes about the three major revolutions resulting in homo sapiens’ rise to the top of the food chain while providing narratives on the ontogenic, phylogenic, and cultural levels of selection. Harari concludes with skepticism about the future based upon our past decision making and current technological advancements. To a behavior analyst, Harari provides explicit reasoning rooted in history, describing examples why we should concentrate our efforts to address world problems. Or perhaps, similar to myself, if you are encouraged to read or listen to a book that doesn’t appear to be related to the behavioral field, Sapiens: A Brief History of Humankind is a worthwhile selection. Nevertheless, given the warm public reception and popularity of Harari’s provocative account, is the world now ready for a behavior-analytic New York Times bestseller?