Narrator: Imagine being a young archaeologist in a remote Greek village in the 1980s. One evening, you see an old man, Mr. George, riding his donkey home from the fields. Walking beside him, carrying a heavy sack, is his wife. To a Western mind, this seems outrageously unfair. Why isn't she on the donkey? When asked, Mr. George gives a simple, baffling reply: "Because she doesn't have one." The answer is self-evident to him, yet utterly alien to his observers. This small moment of culture shock reveals a profound question: are our values—our sense of fairness, equality, and justice—universal truths, or are they shaped by forces we rarely perceive?

In his ambitious work, Foragers, Farmers, and Fossil Fuels: How Human Values Evolve, historian Ian Morris presents a provocative and sweeping answer. He argues that our most deeply held beliefs are not born from pure reason or divine revelation, but are instead powerful adaptations forged in the crucible of how we get our energy.

Narrator: At the heart of Morris's argument is a powerful, and somewhat unsettling, materialist theory: the way a society captures energy from its environment is the primary force that determines its social organization and, consequently, its dominant values. He posits that over the last 20,000 years, humanity has passed through three great stages, each defined by its energy system: foraging, farming, and fossil fuels.

This isn't to say that people in the past were automatons, blindly following economic imperatives. Rather, Morris suggests that each mode of energy capture creates a set of practical constraints and opportunities. Societies that develop organizations and value systems best suited to exploiting that energy source tend to thrive, expand, and outcompete others. Over time, a process of cultural evolution ensures that, as Morris puts it, "each age gets the thought it needs." This framework challenges the idea of values as abstract ideals, recasting them as functional tools for societal survival and success.

Narrator: For nearly 95% of human history, we were all foragers, living by hunting, gathering, and fishing. This way of life, dependent on wild resources, imposed a specific set of values. Foraging societies were fundamentally mobile and small-scale, which made accumulating wealth nearly impossible. As a result, they developed a fierce and actively enforced egalitarianism.

Anthropological studies provide vivid examples of this. Among the !Kung San of the Kalahari Desert, a hunter who becomes too successful and starts acting like a "big man" is quickly brought back to earth. The community will mock him, insult his kill, and speak of his meat as worthless. This isn't cruelty; it's a social mechanism to "cool his heart and make him gentle," preventing the rise of a hierarchy that the foraging lifestyle cannot support. This aversion to hierarchy is so strong that when asked about their leaders, one !Kung man famously replied, "Of course we have headmen! In fact, we’re all headmen... Each one of us is headman over himself!" Economically, this is reflected in extremely low Gini coefficients—a measure of inequality—which cluster around 0.25 for foraging groups. However, this equality came with a dark side. Without a centralized state to monopolize force, violence was a common and accepted way to resolve disputes, making the forager's world both more equal and more dangerous than our own.

Narrator: The invention of farming, beginning around 10,000 BC, was arguably the most significant transformation in human history. By domesticating plants and animals, humans could extract vastly more energy from the land. This wasn't a conscious choice for a better life; it was a gradual, almost accidental process. A random mutation in a wheat plant, for instance, that made its seeds cling to the stalk rather than scattering was useless for the plant's own reproduction but a boon for human harvesters, who inadvertently selected for this trait over centuries.

This new energy source allowed for massive population growth and sedentary villages, which grew into cities and empires. But it came at a cost. Farming created surpluses, and for the first time, it became possible to accumulate vast wealth. This gave rise to deep and rigid hierarchies. A new social contract, which Morris calls the "Old Deal," emerged. This was the belief that society was naturally divided between a small, godlike elite who ruled and a vast majority who obeyed and toiled. As the 18th-century Swiss peasant Kleinjogg explained to a prince, "You lords and princes must order us peasants what to do, for you have the time to decide what is best for the state, and it is for us peasants to obey." This hierarchy was seen not as an injustice, but as the very foundation of civilization. Inequality soared, with Gini coefficients in agrarian empires like Rome reaching 0.44, and in 18th-century England, a staggering 0.59.

Narrator: Around 250 years ago, the Industrial Revolution shattered the energy ceiling of the agrarian world. By unlocking the concentrated power of fossil fuels, humanity's ability to capture energy skyrocketed. This new energy system required a different kind of society and, therefore, a different set of values. The rigid hierarchies of the "Old Deal" became inefficient. Mass production required mass consumption, which in turn required a large, educated, and empowered middle class.

This shift drove a revolution in values. Political equality, once a radical idea, became a global aspiration. Gender hierarchies, which made functional sense in a farm-based economy, began to crumble. And perhaps most surprisingly, fossil-fuel societies became the most peaceful in history. With complex, interconnected economies, the costs of war became astronomically high, and states became extremely effective at pacifying their populations. The global rate of violent death has plummeted to less than one percent. Yet, our values remain complex. While we champion political and gender equality, we tolerate levels of wealth inequality that would have shocked our foraging ancestors, seeing it as a necessary byproduct of a dynamic, innovative economy.

Narrator: Morris’s grand theory is powerful, but is it too neat? The book itself includes critiques from other scholars who challenge its deterministic sweep. Classicist Richard Seaford points to ancient Athens as a major complication. Here was a farming society that developed democratic institutions, celebrated citizen equality, and produced a cultural explosion—values that look more "fossil-fuel" than "agrarian." Seaford argues that Morris downplays the significance of such exceptions, which can have an outsized influence on history.

Philosopher Christine Korsgaard raises an even deeper question. Morris argues that values are functional tools. But, Korsgaard asks, can a value system function if people come to believe it's only a tool? For a value to motivate us, we must believe it is a real moral value, not just a convenient adaptation. If we all accept Morris's theory, might our values lose their power? Morris's response is unflinching. He rejects any distinction between "positive" values (what people believe) and "real" moral values. For him, it is "positive values all the way down." All values are simply what particular people hold at particular times, shaped by the material world they inhabit.

Narrator: The single most important takeaway from Foragers, Farmers, and Fossil Fuels is that our most cherished values—fairness, freedom, equality—are not timeless, abstract truths. They are the products of history, shaped profoundly by the brute material force of how we capture energy. The book forces us to see that the moral world we inhabit is not an inevitable destination but a specific adaptation to a fossil-fuel-powered civilization.

This leaves us with a deeply challenging question. Our modern values of democracy, human rights, and peace feel right and true, but Morris’s theory suggests they are functional for our current energy system. As we confront the necessity of moving beyond fossil fuels to combat climate change, we must ask: What will happen to our values when the engine that created them is gone? Will a new energy age give birth to a new morality, and will it be one we can recognize?