The Rational Optimist summary

Humanity hasn’t always possessed a natural ability to trade and interact. Early humans existed in small familial or tribal groups and did not produce many significant advances in technology. That changed, however, with the discovery of cooking.

Cooking was the first step in our cultural evolution. More calories can be obtained from a cooked food than a raw food, and it requires less chewing. As a result of cooking, more nutritious food could be shared by more people in less time. Cooking also led to the early specialization of labor: women collected grains and staple carbohydrates, while men hunted larger animals for protein. This, along with the extra nutrition gained from cooking, created a surplus of food, which led to the beginning of trade.

Long before the onset of a trade-based society, most human interactions between strangers were rather violent, and war over limited resources was fairly common. Over time, however, as we started living in larger groups and trading with outsiders, things changed. We developed a deeper sense of trust in each other, which propelled humanity forward and still benefits us today.

Exchange is a uniquely human attribute, and a crucial element in the development of trust. Through exchange, people began to recognize that they could best serve their own self-interest by cooperating with strangers. Both parties could gain value by offering something the other could not make or obtain by themselves, thereby increasing the wealth and knowledge not only of individuals, but also the community.

Before the cultural evolution of trade and the specialization of crop growing, communities could grow no larger than their local food supply would allow. Due to their limited resources, drought or crop failure could prove disastrous.

As trading expanded, however, farmers were incentivized to find more efficient means of growing food. When successful, they could store the surpluses to guard against future shortages or trade them for better equipment. Nine thousand years ago, when Greek farmers began trading with tool makers, they obtained new technology that increased their own productivity and allowed them to specialize their farming even further. Trade made surpluses more common and famines rarer.

The first cities appeared about 7,000 years ago along trade routes in Mesopotamia, where goods from different parts of the world were exchanged. People flocked to these trade routes to obtain wine, metals, olive oil, wheat and wool, or other goods they could not source locally. In the cities, demand for these goods and the products made from them facilitated the first merchants and professional tradesmen. For the first time in history, people could make a living from trade, rather than living off the land.

The rise in new professions was essential to the growth of cities and fostered an increase in global innovation. Successful cities used this technological advantage to create more efficient modes of travel, which, in turn, improved trade. The Phoenicians, for example, used a special timber that was traded in their ports to build boats that were stronger, faster and larger than any others at the time.

The story of civilization is the story of learning to use energy more efficiently.

It started initially when we learned to cook our food, thus gaining more calories from it, and continued when we began to use domesticated crops, allowing us to capture more of the sun’s energy. Soon we were using draught animals to increase productivity, wind power to move our sailboats and streams to turn our waterwheels. Time and again, humans prosper when we make efficient use of stored energy.

Perhaps the most talked about impending calamity of the modern era is climate change. We hear constant dire warnings from experts, politicians and environmentalists warning us that we must change our ways, as the planet is in trouble. But even if you believe the dire predictions, there are reasons to be optimistic.

In fact, the warnings are a result of the world becoming richer. The main reason for a rise in temperature is more fossil fuels being burned in developing countries. This is a result of these countries joining the global trading economy, leading to increased prosperity in the developing world.

All across the Internet, twenty-four hours a day, strangers are sharing photographs, advice, recipes, donations, and even medical records, all without the promise of receiving “real” money in return. Humans are sharing for the sheer satisfaction of helping others, and contributing to a wide network of knowledge that raises our collective knowledge in ways that cannot be underestimated.

Although we all live separate lives in our particular corners of the planet, the entire world is now connected by a revolutionary networking capability: the Internet has become a global city in which the knowledge of almost everyone on the planet can be freely shared. A massive cultural evolution is underway, due to the Internet’s unique capacity to specialize in one thing: exchange.

You only have to look at the incredible achievements of the past to be optimistic about the future. A study of our human history shows a steady advancement of ideas, knowledge and standards of living. Life is always getting better.

This is possible because the world of ideas is infinite. When ideas are shared, they begin to thrive and become stronger. Since the 1800s, our accumulation of collective knowledge has given rise to increasing returns on living standards. When more people understand the concept of a bicycle, for example, then more people will create new uses for it, and new technology based on it. When we discover more efficient ways to share ideas, it raises the bar for all of humanity.

The main message in this book is:

Compared to their counterparts throughout human history, most people living today are richer, healthier and safer than ever before, thanks to the unique human habits of exchange and specialization. Despite the overwhelming pessimism that exists, there is every reason to believe that innovation and technological advancement can help us overcome any obstacle we may encounter.

3-5 great quotes from the book

2-4 actionable ideas from this book in blinks