The Ape Who Tamed Fire — The Beginning of the Energy Revolution

When night fell, it grew dark; when the cold came, they shivered. That was simply how things were for almost every animal living on the earth. Yet at some point a creature close to an ape did not turn its back on the blazing flames but instead drew near to them. A wildfire left by a lightning strike, embers smoldering at the foot of a volcano — it was probably such accidental flames that, when this creature learned to guard them from going out, to carry them, and eventually to kindle them with its own hands, marked the start of the long story of humankind and energy. Energy, at its core, is the ‘power to move something, to warm it, to make it bright.’ The history of humankind has also been an endless quest over where to draw that power from.

Fire — The First Power We Grasped

The first energy humankind grasped was fire. By burning branches and dry grass — that is, firewood — people obtained heat and light. The darkness retreated, and night turned into a time for activity. The cold eased, and humans extended their living grounds even into chilly lands that would otherwise have been hard to inhabit. To gather around the fire was also a defense that kept enemies at bay.

Fire brought more than warmth and light. Food cooked over a flame becomes softer and easier to digest than when raw. Some have argued that heated meals aided the absorption of nutrients and supported the development of the human body and brain. There are many views on this, and not everything is certain, but it is widely accepted that becoming able to handle fire was an event that greatly changed the human journey.

In time, fire also became a power for making things. Knead clay and bake it, and a sturdy earthenware is born. As people learned to control even higher heat, smelting began that drew metals out of ore, and tools of copper and iron reshaped the world. From cooking to ceramics and on to metallurgy — firewood, and the charcoal made by smoldering it, were the first energy sources that supported the foundations of civilization.

Muscle, Water, and Wind — Power Borrowed from Nature

Even though fire gave heat and light, carrying heavy loads and tilling fields required a different power. For a long time, the leading role belonged to muscle. First the muscle of people themselves. And then the strength of domesticated animals such as oxen and horses — animal power. Once livestock could be used for farming and transport, the land a single person could work expanded, and more food could be produced. The back of a horse and the ox cart also became means of carrying people and goods far away.

The use of animal power was not limited to merely dragging heavy loads. Ingenuity for drawing out an animal’s strength well was slowly accumulated. The improvement of the harness that let a horse pull loads without strain, the horseshoe that protected hooves, the development of the plow for tilling fields efficiently — all were forms of wisdom for extracting more power from the same animals. The more power that could be drawn from a single horse or ox, the wider the land that could be tilled and the more people that could be fed. How to use up the limited resource of animal muscle as skillfully as possible — pre-modern people poured their wisdom into this too.

Even so, the power that can be drawn from muscle has its limits. People and animals alike grow tired, must be fed, and must be rested. So humankind turned its eyes to a power outside the bodies of themselves and their animals — the power of nature itself. The foremost examples are flowing water and blowing wind.

A waterwheel is a mechanism that turns the force of a river’s flow or of falling water into rotation. Records remain of its use in the Mediterranean world since before the common era, and in medieval Europe it spread with striking momentum. The eleventh-century English land survey, the Domesday Book, is said to have recorded over five thousand watermill sites. Waterwheels were first used for milling grain, and in time their uses widened to beating cloth, working the bellows of a smithy, and sawing timber. Windmills too spread in Europe from around the twelfth century, milling grain even in lands with little water and, in low-lying regions, pumping up water to support land reclamation.

The Invisible Ceiling of Pre-Modern Society

Fire, muscle, water, and wind. The powers that pre-modern humankind could grasp stayed roughly within this range. And each of them had a ceiling that was hard to break through.

Firewood and charcoal, traced back to their source, are wood. Wood takes long years to grow after it is planted. As people made iron in abundance, warmed their homes, and kept on cooking, the forests dwindled before their eyes. In fact, there were regions where forests were said to have been greatly lost for the fuel of iron-making and daily life. Even to increase animal power, one needed pasture and fodder to feed the livestock. Waterwheels and windmills could only be placed by riversides or in the paths of the wind, and they were at the mercy of nature’s whims.

In other words, the total amount of energy a pre-modern society could use was firmly bound to the amount of grass and trees that the land produced in a single year, to the area that could feed livestock, and to the strength of the flowing rivers and blowing winds. No matter how the population grew or how it prospered, there was an upper limit on the usable power that nature had set. It was precisely this invisible ceiling that long held down the scale of human life.

Put another way, the power that pre-modern humankind could use was mostly the power that nature newly produced each and every year. The rain that fell this year flowed down the rivers, the grass that grew this year was grazed by livestock, the wood that grew this year became firewood. Humankind managed, as it were, within the range of the ‘allowance’ that nature gave. That is why poor harvests, droughts, and storms meant a shortage of food and, at the same time, a shortage of power itself. When energy was scarce, the things that could be made, the things that could be carried, and the people that could be fed were all limited. Abundance and famine, prosperity and decline, were inseparably bound to the amount of power that land could draw out in that year.

This limit was so taken for granted that it did not even rise into people’s awareness. Keep the fire burning, feed the livestock, turn the waterwheel — within that range the world went round, and for a long time no one doubted it. The power of kings, the size of cities, the number of armies — all, at their core, were supported by the amount of energy that the land could draw out.

And yet. A power to break through this ceiling lay sleeping right beneath their feet. Deep underground, a black stone into which ancient plants had transformed over a span of time dizzying to contemplate — coal. It was, so to speak, the ‘power of past suns,’ stored in the earth over millions of years. When humankind eventually dug up this black stone, burned it, and poured its heat into a new machine, the upper limit nature had set was broken through for the first time. The ape who tamed fire had thus come to stand at the entrance of the next revolution.