This article is part of our Summer reads series. Visit our collection to discover “The Economist reads” guides, guest essays and more seasonal distractions.

Economics has a reputation as a dry, heartless subject, full of boring equations. The reality is much more interesting. Thinking like an economist, as I see it, comprises two main features. The first is always to think about trade-offs. There is no such thing as a free lunch, as Milton Friedman said. When someone gets something, they almost always give something up in return. If you go out with your friends, you won’t have time to go to the gym. If an economy’s wages go up, dividends might go down, or inflation might go up. And so on. The second is to try, when possible, to put numbers on things. When we say that China’s lockdowns are “strict”, what do we actually mean? If you think “job quality is getting worse every year”, how are you going to measure that? Sometimes it is not easy to quantify ideas, but it’s always good to try. In The Economist’s coverage we always try to remember these two lessons. Here are five books that should help you think in this way.