Only those who can't afford to wear shoes and have to walk barefoot everywhere will know how much time and energy a bicycle can save them and how much it means for them to get better health and higher income.

This four-level framework based on income levels is an alternative to an overly emotional, bifurcated worldview. It is also the most important component of building a realistic worldview. Now you understand that this method isn't that complicated, right? In the remainder of this book, I will continue to use this four-level income division to explain almost all social phenomena. From the function of the elevator, to the number of people who have died from drowning, to the gender division, to the cooking method, and the number of black rhinos. This method will help you understand the world more clearly and make better judgments.

How can you capture all your misconceptions? Data. You have to rely on the data and describe the real world behind it. I would like to thank UNESCO for its statistics, as well as bubble maps and the Internet. But data alone is not enough, only when you have a simple and correct way of thinking, the wrong ideas will be replaced and then disappear. That's why we've introduced a four-tier divide based on income level.



, and you will quickly realize that this statement describes a polarized picture, and there is a huge gulf between the two poles. In reality, this gap often does not exist, and the vast majority of people live in the middle.

To effectively control our false instinct of splitting in two, we need to insist on looking for the vast majority.

We should be careful about the practice of comparing only the averages. In addition to the average, we also need to pay attention to the actual distribution of the data. If there is an overlap in the distribution of data between the two groups, then it is possible that the gap between the two groups does not exist.

We need to be careful about the practice of only comparing extreme cases. In all groups, countries or people, there will always be extreme situations, there will always be tops and bottoms. And the difference between the top and the bottom is sometimes extremely unfair. Even so, most are still distributed in the middle, and there is no chasm in the middle.

We should pay attention to the practice of only looking down and not looking up. Remember that looking down creates the illusion that everything looks the same short, but that's not the case.



The smell of urine, and the feeling that the inside of my nose and mouth were stuffed with sludge and I couldn't breathe. I remember struggling desperately to get myself on my feet, but sinking deeper and deeper into the slimy mud. I remember desperately stretching out my arms, desperately trying to grab a straw, and then suddenly being pulled out of the mud. My grandma pulled me out, put me on the kitchen floor, and gently rinsed me with warm water. I smell the scent of soap.

It was when I was 4 years old and accidentally fell into a gutter in front of my grandmother's house. The gutter, which had rained overnight and was mixed with a lot of sludge from the factory, was so completely filled that it was hard to see the edges. I accidentally walked to the edge of the gutter and planted myself head and foot in the ditch. My parents were not with me at the time, my mother was hospitalized with tuberculosis, and my father had to work more than 10 hours a day.

When I was living with my grandmother, my father would take me to the hospital on his bicycle every weekend. He put me on the back seat of the bicycle and deliberately rode in a big circle to amuse me. When I got to the hospital, I would see my mom coughing on the balcony from a distance. Dad told me that we couldn't go into the room to see Mom or we would get infected. I could only wave to my mom from afar, and then she waved to me too. I could see her saying something to me, but her voice was too weak for me to hear what she was saying. I always remember that she was smiling at me.



More attention. This instinct for negative thinking is the second reason behind our major misunderstandings.

The world is going bad. That's what I hear most often. I must admit that there are a lot of bad things going on in this world.

The number of people killed in the war has dropped dramatically since World War II, but the war in Syria has brought a lot of casualties, and international terrorism is on the rise. We will discuss the topic of terrorism in Chapter 4.

The deterioration of marine ecology is a cause for concern. And dead zones in the ocean, as well as the number of endangered animals, are increasing.

Glaciers are melting, and sea levels are likely to rise by one metre in the next 100 years. And we can be pretty confident that the melting of glaciers won't stop anytime soon because of the greenhouse gases we emit, even if we stop emitting more greenhouse gases into the atmosphere.

The illusion that real estate investment is risk-free led to two crashes in the U.S. housing market, in 1993 and 2008. There will still be similarly complex and similar crises in our financial system, perhaps tomorrow.

If we want the world to have a stable financial system, peace and the protection of natural resources, then there is one thing we must do, and that is international cooperation. And the basis of international cooperation is that we have the same realistic, realistic understanding of the world. Therefore, ignorance of the real state of the world is the greatest obstacle to international cooperation.

Experiment to verify it. In 2016, I asked people in 30 countries and territories the following question. The question is the one mentioned above: Do you think the world is getting better, for the worse, or staying the same?

The diagram on the previous page shows everyone's answers.

I've never trusted data 100 percent, and neither should you, there's always some uncertainty in the data. In this case, I would assume that the numbers are roughly correct, but you should not draw conclusions based on a difference of less than 10%. (By the way, in statistics, there's a good basic principle: don't jump to any conclusions when the difference is less than 10 percent.) In the statistics above, the conclusion is very clear, the vast majority of people believe that the world is going bad. Then we are so nervous and anxious, and it is a matter of course.

The numbers are roughly correct, but you shouldn't draw conclusions based on a difference of less than 10%. (By the way, in statistics, there's a good basic principle: don't jump to any conclusions when the difference is less than 10 percent.) In the statistics above, the conclusion is very clear, absolutely