Numbers Don’t Lie: Book Overview (Vaclav Smil)

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What is Vaclav Smil’s Numbers Don’t Lie about? What is the key message to take away from the book?

In his book Numbers Don’t Lie, Canadian scientist and economist Vaclav Smil wants to help you understand the world by understanding numbers and statistics. Numbers can help you see the world more clearly, but only if you know what they’re actually saying.

Below is a brief overview of Vaclav Smil’s Numbers Don’t Lie: 71 Things You Need to Know About the World.

Numbers Don’t Lie: 71 Things You Need to Know About the World

In his book Numbers Don’t Lie, Vaclav Smil argues that numbers, when used correctly, can help us understand the world. But people often misunderstand what certain metrics are saying or use statistics that don’t tell a complete story. To get an accurate view of the world, we must place numbers in the proper context and understand how they were calculated. To figure out what the many numbers and metrics used in the modern world are saying requires a basic understanding of science and statistics. More importantly, however, it requires effort. You must be willing to pay attention, and to look beneath the surface of a simple statistic and try to see what it says about the world.

In this guide, we’ll first look at some commonly used metrics and what they actually say about the world and its inhabitants. Then, we’ll look at the stats about some of the most economically powerful countries and what the numbers say about their futures. Finally, we’ll examine the numbers on humanity’s most pressing environmental issues, such as greenhouse gas emissions, sustainable energy, transportation, and food production. 

Commonly Used Metrics and What They Say About Countries and Populations

Metrics on GDP, unemployment, population growth, and happiness levels, to name a few, are used regularly by the media and are often taken at face value by the general public, claims Smil. But what do these numbers actually tell us? And what information do they leave out? Let’s look at a few commonly used metrics and determine their significance.

Metrics on Population Happiness Aren’t Fully Accurate

We should always take reports of a country’s happiness with a grain of salt, as happiness is difficult to measure, writes Smil. He argues against the validity of the World Happiness Report, which the media regularly cites as an accurate measure of the quality of life in different countries. 

This report calculates happiness using several variables: GDP per capita, social support, life expectancy, freedom to make life choices, generosity, and perception of corruption. GDP, as we’ll discuss further, is not a good indicator of quality of life. Other variables, like freedom of choice and perception of corruption, depend too heavily on subjective answers that are difficult to compare across cultures. 

Gross Domestic Product Doesn’t Quantify Quality of Life

Gross Domestic Product (GDP) is the total annual value of all goods and services transacted within a country, and economists often use it to measure standard of living. Smil argues that GDP, while a decent measure of overall economic strength, is an unreliable measure of quality of life because it fails to take many factors into account. For one, GDP doesn’t factor in population size, which means it only looks at overall economic output and not output per citizen—thus, larger countries may have larger GDPs simply because they have more citizens, not because each citizen has a higher standard of living. GDP per capita (total GDP divided by population) would be a better measure to use for this. 

But GDP per capita still doesn’t factor in differences in cost of living and exchange rates between countries, making comparisons unhelpful. For that, we’d need to use GDP per capita at purchasing power parity, a measure that uses the prices of goods among different countries to compare currency valuation. Even this metric, however, doesn’t account for income inequality or the availability of social safety nets, huge factors in determining the average standard of living.

Unemployment Rates Don’t Accurately Depict the Health of a Nation’s Workforce

According to Smil, another unreliable metric used to broadly measure economic strength is a nation’s unemployment rate. The main reason official unemployment rates don’t paint an accurate portrait of a country’s labor force, he argues, is that they exclude people who aren’t actively seeking employment. A country may have a low official unemployment rate but a high percentage of people who aren’t working because they gave up seeking employment. 

The labor force participation rate is a better indicator of a country’s workforce health, as it’s a measure of all people above the age of 16 who are available to work, including those who aren’t looking for work. In the US, the labor force participation rate peaked in 2000 at 67%. As of 2019, it was around 63%. For comparison, the unemployment rate in 2000 peaked at 4.1% and was around 3.5% in 2019. These unemployment rates would indicate that the labor market has improved in that timeframe, but the percentage of people working has actually gone down

The Infant Mortality Rate Accurately Reflects the Standard of Living

Smil argues that the infant mortality rate is a better indicator of standard of living than GDP per capita. The infant mortality rate is such a powerful indicator because it accounts for factors that GDP ignores, like income inequality, social support, a strong healthcare system, good education, and safe and clean living conditions. 

From 2015 to 2020, Finland, Japan, and Slovenia had extremely low infant mortality rates (around two per 1000 live births). The United States, with the highest GDP in the world, had triple that amount at six per 1000, suggesting that the higher GDP of the US fails to capture important quality-of-life factors that those other countries provide their citizens despite their lower GDP. 

High Vaccination Rates Correlate to a High Standard of Living

Smil argues that vaccines are the most cost-effective way to increase a country’s standard of living. Vaccines greatly reduce infant mortality rates and save millions of lives, both young and old, every year. The measles vaccine alone is estimated to have saved 14 million lives from 2011 to 2020. 

Because they’re so effective at preventing disease, vaccines also have enormous economic benefits. A 2016 study found that for every dollar invested in vaccines, $16 are saved in healthcare costs and prevention of lost wages due to illness. When looking at broader economic benefits, up to $44 are saved for every dollar spent. 

Thanks to their economic benefits, increased vaccination rates could go a long way in lifting underdeveloped nations out of poverty, writes Smil. From 2000 to 2016, vaccination rates rose from 50% to 80% among low-income nations. If these increases continue, we could see many more prosperous nations in the 21st century.

Dropping Fertility Rates May Lead to a Decline in Quality of Life

According to Smil, falling fertility rates have the potential to significantly alter global dynamics in the 21st century. Fertility rates, or total births per woman in a given population, have changed drastically in the last century, especially in developed nations. From 1950 to 2000, the global fertility rate dropped from around 5 to 2.6. 

To maintain a stable population size, you need a fertility rate of approximately 2.1. Countries with sustained fertility rates below 2.1 will see a gradual population decline, which can have detrimental effects. By 2050, it is estimated that three-quarters of the global population will live in countries with a fertility rate below the replacement level of 2.1. Many developed nations are already well below this level. In 2019, Japan, Spain, Italy, and Romania had fertility rates of 1.3. Japan, Ukraine, Greece, and Croatia sat at 1.4. 

If these trends continue, there will be severe economic repercussions, writes Smil: To grow economically, a society needs a young labor force to maintain infrastructure and take care of the elderly. Developed nations with increasingly low fertility rates will likely see a sharp decline in standards of living as the country buckles under the weight of increased healthcare costs, labor shortages, and lower economic output. To combat low fertility rates, many countries will likely implement policies that encourage childbirth and immigration, but it remains to be seen if that will be enough to maintain population size.

Assessing the Well-Being of Economically Powerful Countries

Now that we’ve examined some common metrics, we’ll look specifically at a few prominent countries and what the metrics are for them. Smil argues that the most important measure of success for a country is not its GDP, as many believe, but the well-being of its citizens. The way we over-value economic success can be seen in the top three countries by GDP: the United States, China, and Japan. Though on the surface these countries may seem to thrive, a closer inspection tells a different story. Let’s examine each country. 

The United States

Smil points out that the US isn’t as exceptional as many think. Though it’s an economic powerhouse, the US is profoundly lacking when measuring the prosperity of its people. Its infant mortality rate, as mentioned above, sits at 6, which ranks 33rd out of 36 nations in the Organisation for Economic Co-operation and Development (OECD). This can largely be attributed to the country’s lack of universal healthcare, which every other wealthy nation has. Furthermore, out of the 36 OECD nations, the US ranks first in obesity percentage and 28th in life expectancy. 


Japan saw a tremendous rise in economic and social prosperity in the 20th century, but Smil argues that the country is declining rapidly for a number of reasons. 

After World War II, Japan quickly grew to be a global powerhouse. In 1978, Japan became the world’s second-largest economy and continued to flourish throughout the 80s. By 2000, however, Japan’s stock market was half of its 1990 peak, and many of its strongest companies struggled to remain profitable.

Though it still has a low infant mortality rate and good standard of living, there are concerns that Japan will continue to decline in the 21st century. Japan has had to deal with the increasing costs of natural disasters like the 2011 tsunami, and its relations with China and South Korea are worsening. Perhaps most worrying, however, is Japan’s population, which is expected to drop from 127 million to 97 million by 2050. With an aging society, it will be difficult to maintain Japan’s construction, transportation, and healthcare infrastructure.


Though China has grown tremendously in the past 40 years, Smil questions its ability to maintain this growth in the coming decades. Even as its GDP has grown to rival the United States, the average quality of life for Chinese citizens is far from ideal. Its per capita GDP by purchasing power parity ranks 73rd in the world. 

Like Japan, China also faces the risks of an aging population, and its economy may not grow quickly enough to make up for it. Its percentage of economically active people peaked in 2010. As the country’s average age increases, its dominant manufacturing and industrial economies are expected to decline without enough young labor to support its growth.

Another factor impacting the well-being of China’s citizens is pollution, which has become a huge problem as the country has grown economically, says Smil. Air quality falls well below health standards in its biggest cities: Beijing averaged 80 particulates per cubic meter of air in 2015, over three times the World Health Organization’s maximum acceptable level of 25. Some Chinese cities regularly exceed 500 particulates per cubic meter. This extreme pollution is expected to increase respiratory and heart disease and decrease expected lifespans.

Metrics on Environmental Challenges of the Modern World

Now that we’ve discussed numbers about populations and countries, let’s look at some important numbers about the environment. Smil argues that the main challenge we face in the modern world is how to continue raising standards of living for billions of people while sharply decreasing our carbon emissions

Unfortunately, when looking at the numbers, this challenge is close to impossible. We simply rely too much on fossil fuels to power the global economy, and the technological advances we would need to make to replace carbon-heavy industries are unlikely to happen in the near future. It’s important, however, to look at the facts and be realistic about the challenges we face. Let’s do that by first examining our carbon emissions and the failure of technology to protect us from environmental degradation. We’ll then look at a variety of areas that impact the environment and the numbers associated with those. 

Significantly Curbing Carbon Emissions Will Be Nearly Impossible

To help understand our environmental challenges, Smil provides the numbers for the amount of carbon we emit through the use of fossil fuels. At the beginning of the 19th century, global carbon emissions were relatively low at around 10 million tons a year. By the end of the century, that number was over half a billion tons. And by 2000, global carbon emissions were over seven billion tons a year. To put it another way, from 1800 to 2000 carbon emissions grew 650-fold while the global population only grew sixfold.

Even as governments and other organizations have started to implement large-scale efforts to curb carbon emissions, global emissions continue to grow, writes Smil. By 2017, emissions had declined in Europe and the United States, but those declines were offset by China, which contributed three billion tons of carbon emissions. 

More recently, China’s increase in carbon emissions has slowed, but emissions in India and Africa are expected to continue growing, making any substantial decreases in overall global emissions unlikely. Even if we meet the targets set forth by the Paris Agreement of 2015, an international committee dedicated to reducing carbon emissions, carbon emissions would still be about 50% greater than their 2017 levels. 

If we are to avoid environmental disaster, scientists estimate we need to keep global temperatures from increasing more than 1.5 degrees Celsius. According to a 2018 study, the only way to do this is to get to zero net emissions by 2050. Smil claims reaching zero emissions by 2050 will take an unprecedented global effort on a massive scale.

We Rely Too Much on Technology to Save Us From Environmental Destruction 

Smil argues that many people wrongly believe technology can save us from environmental disaster. This is because they often have unrealistic expectations about the speed at which technology will advance. 

These unrealistic expectations are often because people are influenced by the numbers underpinning Moore’s law, which states that the speed and capabilities of computer chips double every two years. This law has largely held true since its inception in 1965, and it has allowed for a great deal of innovation in computers and electronics. 

People often assume the same rate of progress applies to other fields—for instance, in environment-related industries—but technological progress happens much more slowly outside of computer-based technologies. For example, corn yields have risen by an average of only about 2% per year since 1950, and fuel efficiency has increased by about 2.5% a year. 

Instead of relying on future technologies to save us, we should be searching for realistic and practical solutions, and if a problem can’t be completely and immediately solved, incremental progress is still better than no progress at all, contends Smil. 

The Numbers on Sustainable Energy 

A key environmental challenge of the 21st century is transitioning our energy sources away from fossil fuel consumption. Smil argues that we must be realistic about this transition, and understand the numbers behind it if we wish to make meaningful progress. 

Energy transitions take time. The transition from wood and charcoal to coal, oil, and gas as the world’s main source of energy took a century. Transitioning away from fuels that currently produce 10 billion tons of annual carbon emissions will be a much more difficult task. While alternative energies like solar, wind, and nuclear are being adopted, they won’t be able to replace fossil fuel consumption any time soon. In this section, we’ll go over each of these energy alternatives and provide further insight into our reliance on fossil fuels.

Nuclear Energy Isn’t Strong Enough to Reduce Our Dependence on Fossil Fuels

Many point to nuclear energy as the best possible replacement for fossil fuel energy; when it began to take off in the 1970s, some predicted it would provide virtually all of the world’s electricity by 2000. However, Smil argues that it has failed to do so for several reasons.

Catastrophic failures of nuclear power plants occurred at Three Mile Island, Pennsylvania, at Chernobyl, Ukraine, and at Fukushima, Japan, which has made the public and governments more skeptical of nuclear energy. Also, the constructions of many nuclear plants have gone over budget, there is still not a viable option for permanent storage of nuclear waste, and we still haven’t come up with a safer, less expensive design for new reactors. 

For these reasons, the prominence of nuclear energy has receded, especially in the Western world, writes Smil. Germany and Sweden are removing nuclear energy entirely, and France, the leading adopter of nuclear energy, is also cutting back. As a result, the percentage of global electricity powered by nuclear energy has gone from 18% in 1996 to 10% in 2018. Though nuclear power still has the potential to drastically reduce carbon emissions, it isn’t on track to do so, as it is estimated to provide only about 12% of electricity by 2040.

Wind Energy Requires Fossil Fuel Inputs

According to Smil, numbers don’t suggest that wind turbines will provide an efficient solution to environmental problems, either. The main issue with wind-generated electricity is the amount of fossil fuel required to build wind turbines. Though a wind turbine can generate the energy it took to produce it in less than a year, these turbines only produce energy intermittently, and we need large amounts of steel, oil, and cement to make them. For wind to provide just a quarter of the world’s electricity by 2030, we’d need around 450 million tons of steel, which as of now can only be made using coal and natural gas. Until we can make wind turbines using only renewable resources, we will continue to depend on fossil fuels.

Solar Energy Is Growing Slowly

Solar energy, though efficient, provides more evidence to Smil’s argument that energy transitions take time: The photovoltaic effect, the generation of electricity when a material is exposed to light, was first discovered in 1876. Yet it wasn’t until the 21st century that solar electricity generation became efficient enough for large-scale usage. In 2000, solar power provided 0.01% of global electricity. In 2010, that number went up to 0.16%. By 2018, it was at 2.2%. This is a sharp rise, and with solar energy becoming more efficient, it could certainly make a dent in global carbon emissions. But it isn’t likely to replace fossil fuels entirely.

Battery Improvements Will Be Necessary to Store Renewable Energy

If we hope to provide year-round renewable electricity to big cities through wind and solar power, we’ll need better batteries to store saved-up energy more efficiently, claims Smil. This is because there are gaps in the flow of wind and solar energy: For instance, an unusually cloudy or windless month could render a city’s solar panels or windmills inadequate. 

As of now, lithium-ion batteries are the best thing we have, but they are still too inefficient to hold enough power for a city of millions. We’ll probably need something more efficient, like hydrogen-based or compressed air batteries, but the technology for those is still in early development.

The Environmental Footprint of Transportation and Shipping

Statistics show that another significant contributor to carbon emissions is transportation and shipping. Smil argues that it will take a radical change to go carbon-neutral in these industries. From cargo ships to airplanes to cars, the entire world now runs on fossil fuel-powered vehicles. Let’s look at the numbers behind the transportation and shipping industries. 

Diesel Engines Will Continue to Dominate

According to Smil, diesel engines are an integral part of the globalized economy. Diesel engines are much more efficient (15 to 20%) than their gasoline-powered counterparts, and they are reliable, durable, and have relatively low operating costs. Because of this, they power virtually every container ship, truck, and freight train, moving our most important commodities (oil, cement, grain) around the world. There is simply no better way to transport the massive amount of materials than diesel engines, and this will remain true for the foreseeable future. 

Electric Container Ships Won’t Be Efficient Enough in the Short Term

Though we’ve successfully built electric trains and cars, Smil points out that building efficient electric container ships will be a monumental task. The first electric container ship, built in the late 2010s, can only carry 120 containers, will travel at a slow speed of six knots, and will only be used for trips of up to 30 nautical miles. In contrast, diesel-powered container ships can carry over 20,000 standard-sized containers, travel at a speed of 16 knots and commonly make trips of over 20,000 kilometers. 

To match the production of diesel, container ships would require lithium-ion batteries over 10 times more efficient than what we have today. To put this in perspective, in the last 70 years the efficiency of commercial batteries hasn’t even quadrupled.

Both Carbon-Producing Cars and Electric Vehicles Produce Significant Emissions

Smil argues that the age of the car began on August 12, 1908. This was the day the first Model T was assembled, making cars a much more affordable commodity. The automobile has had an enormous impact on the world but is also a major contributor of carbon emissions. We’ll look at the numbers behind vehicles to explain why they are so inefficient as a means of transportation and why electric cars won’t save us.

Cars Use Energy Inefficiently

According to Smil, the main reason cars are energy-inefficient is their large weight-to-payload ratio—in other words, the weight of the car versus the weight of the people it’s carrying. This means it takes a huge amount of energy simply to move the car itself, not the passengers in it. For comparison,  a Ford F-150, the most popular American car, has a ratio of 32, a bike has a weight ratio of 0.1, and a Vespa scooter 1.6 (for an average-sized human).

To make matters worse, in the US, almost three-quarters of Americans commute to work without other passengers, so the weight-to-payload ratio is especially bad. What’s more, the average car size is only increasing, especially with the heavy batteries required for electric cars. And while lighter cars would help, having fewer people drive alone would be the best thing to do to reduce the weight ratio of cars. 

Electric Vehicles Also Produce Significant Carbon Emissions

While electric vehicles (EVs) can help with carbon emissions, Smil argues that they aren’t an effective means of displacing carbon just yet. First, since global electricity still mostly comes from fossil fuels, simply powering EVs will continue to be a source of carbon emissions. Further, as we’ve discussed, building the infrastructure for renewable energy takes fossil fuels, so even getting to the point where many people drive sustainably powered EVs will require a lot of carbon, as will producing the EVs. 

To add to this, EV production also creates about three times as much toxicity as a gas-powered car. This is due to the use of more heavy metals, which are more toxic to both humans and our freshwater sources. 

Airplanes Would Need to Run on Biofuel to Reduce Their Carbon Footprint

According to Smil, the numbers show that eliminating the carbon footprint of air traffic will be another great challenge of a transition to a carbon-free world. Airplanes use kerosene-based jet fuel, and there is currently no viable alternative to that. The best alternative may be fuel from organic matter, but to meet the increasing demand for air travel with biofuel, we’d need to cultivate oil-rich crops, which have their own environmental issues (more on this later). 

Further, like container ships, making electric airplanes will be difficult, as batteries are heavy and a plane needs to be as light as possible to function properly. Of course, the most practical and effective way to limit airplane emissions would be to limit air traffic, but airplane use is expected to continue growing in the coming years.

Trains Are an Excellent Medium-Distance Mode of Transportation 

As Smil points out, no mode of transportation is as efficient for medium distances as a high-speed electric train. While high-speed trains can’t replace the intercontinental capacity of planes or the local capacity of cars, they’re the best option for travel between these extremes. 

For inter-city travel, trains offer high speeds, convenience, and relatively low energy usage and carbon emissions. A high-speed train can cover 300 kilometers in just under two hours. This is just a little bit longer than an airplane takes at a fraction of the energy usage. While Europe and China have adopted the use of electric trains, the United States is lagging behind: There’s not a single high-speed train connecting major cities in the US. 

Food Production’s Contribution to Carbon Emissions

Our food production also plays a big role in climate change, and as the global population continues to rise, Smil argues we must make changes in the way we produce and consume food. We’ll look at the numbers of three key aspects of food production: the use of nitrogen fertilizer, food waste, and meat consumption. 

Nitrogen Fertilizers Are Harmful

Smil argues that the use of synthetic nitrogen fertilizers impacts the environment in two major ways: It adds to greenhouse gas emissions, and it causes nitrogen to be removed from the soil. Crops need nitrogen, and the traditional ways farmers supplied nitrogen to crops (recycling organic materials and rotating crops) are no longer adequate as the population now reaches close to 8 billion people. To provide nitrogen to crops, we synthesize almost 150 million tons of ammonium a year to make fertilizers, a process that’s environmentally harmful. Let’s look in more detail at fertilizers’ impact on greenhouse gas emissions and soil nitrogen. 

Nitrogen Fertilizers Emit Greenhouse Gases

Though carbon dioxide contributes the most to the heating of the Earth, Smil points out that the next largest contributors are methane and nitrous oxide. The production and use of nitrogenous fertilizers add all three of these gases to the atmosphere. The synthesis of ammonia requires a lot of energy, usually provided by the burning of coal, which emits carbon dioxide, or natural gas, which in turn emits methane. The use of fertilizers also adds nitrous oxide to the atmosphere. Altogether, synthetic nitrogen fertilizers are estimated to account for about 1% of global greenhouse gas emissions.

Nitrogen Fertilizers Lead to Nitrogen Loss

According to Smil, nitrogen fertilizers also contribute greatly to nitrogen loss, which affects crop yields and makes us more dependent on synthetic nitrogen. Nitrogen loss happens when the nitrogen naturally found within the soil decreases. As more and more nitrogen is removed from the soil, crop yields become smaller, which could lead to widespread hunger and famine. Because of this, farmers will have to increase their use of synthetic nitrogen fertilizers, further adding to the problem. 

To avoid this vicious cycle, we must find a way to reduce the use of nitrogen fertilizers, whether through increased fertilizer efficiency or a more sustainable, natural supply of nitrogen. 

Food Waste Exhausts Labor and Energy and Harms the Environment

Smil argues that reducing global food waste would greatly benefit the environment. The amount of food humans waste is massive. According to the UN, at least a third of all harvested food is wasted. The biggest contributor is the United States, with over 40% of food going to waste—an amount that would be enough to feed about 230 million people annually. 

Further, when we waste food, we also waste a great deal of labor and energy while furthering the damage to the environment. If we wasted less food, we’d have less soil erosion, nitrogen loss, and greenhouse gas emissions. 

Meat Production Requires a Huge Amount of Crops to Feed Livestock

Another change Smil advocates that could have a great environmental impact is limiting the consumption of meat, especially beef. Reducing all meat consumption would be helpful, but we could make a substantial impact just by eating more chicken and less beef. 

Numbers Don’t Lie: Book Overview (Vaclav Smil)

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Darya Sinusoid

Darya’s love for reading started with fantasy novels (The LOTR trilogy is still her all-time-favorite). Growing up, however, she found herself transitioning to non-fiction, psychological, and self-help books. She has a degree in Psychology and a deep passion for the subject. She likes reading research-informed books that distill the workings of the human brain/mind/consciousness and thinking of ways to apply the insights to her own life. Some of her favorites include Thinking, Fast and Slow, How We Decide, and The Wisdom of the Enneagram.

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