Book SummaryDon't Trust Your Gut, by Seth Stephens-Davidowitz

1-Page Summary1-Page Book Summary of Don't Trust Your Gut

The normal state of human existence is to stumble blindly through life, making it up as we go along. From time to time, we turn to experts—philosophers, spiritual teachers, business leaders, and self-help gurus—for guidance on how to live our lives. While people have found all these paths useful to some degree, the overall results can be decidedly mixed. Clearly, no one’s figured out the formula to a happy, well-lived life. But what if all our technological progress has inadvertently created a tool to do just that?

In Don’t Trust Your Gut, published in 2022, Seth Stephens-Davidowitz argues that with the advent of “big data”—the vast amount of information now available on human behavior—we can scientifically analyze the outcomes of millions of people’s life decisions. Doing so gives us definitive answers to which of the many choices we make have the most impact on our...

Don't Trust Your Gut Summary The Power of Numbers

The title—“don’t trust your gut”—speaks directly to Stephens-Davidowitz’s basic premise: namely, that hard data is a better guide to making decisions than human intuition. Let’s look at the reasoning behind this statement, where the data we might turn to comes from, and what that data says about the role of deliberate decision-making versus chance.

(Shortform note: Stephens-Davidowitz explores data-driven decision-making in layman’s terms, but if you’re interested in crunching the numbers yourself, Steven Silbiger’s The Ten-Day MBA offers a guide to various data analysis tools that are commonly used in the business world. One tool is the decision matrix, wherein you compare different options by scoring them based on factors that are important to you and determine the best choice from there. Other tools you can use are probability analyses and regression analyses....

Don't Trust Your Gut Summary The Numbers on Love

The first aspect of life that Stephens-Davidowitz puts under the data microscope—and one where the “try and try again” rule clearly applies—is the realm of romantic attraction, dating, and marriage. Information from online dating platforms paints a pretty clear picture of what people search for in romantic partners, some of which, like personal appearance, are factors you can improve to raise your dating marketability. However, the attributes that make someone initially attractive don’t carry any statistical weight when it comes to maintaining a lifelong relationship.

The Data of Attraction

Stephens-Davidowitz summarizes online dating data thusly: Good looks are the most important factor, especially for women, while men’s attractiveness also depends on income and career. Drilling deeper into the numbers, he finds that when trying to find a date online:

• Being traditionally attractive accounts for nearly a third of women’s successes at finding a match, but isn’t as important for men (though it still matters). What does count for men is height, with tall men receiving the bulk of romantic attention.
• Income is also a strong determinant of success, but is twice as...

Don't Trust Your Gut Summary The Numbers on Success

Just as hard data can give you the tools to be rational in your pursuit of love, it also acts as a guide to financial success. According to Stephens-Davidowitz, researchers working with anonymized taxpayer data have determined that more than 80% of the richest people in the US are those who started a business. However the data also reveals that popular beliefs about entrepreneurship are wrong, that the road to wealth is long and boring, and that your odds of achieving runaway financial success are highly dependent on which field you enter.

(Shortform note: Stephens-Davidowitz doesn’t claim that starting a business is an automatic path to wealth—he’s clear that only some businesses are successful, as we’ll cover later in this section. What he doesn’t bring up are business failure rates—according to the US Bureau of Labor Statistics, less than 35% of businesses survive for more than 10 years. Agriculture businesses have the highest longevity rates while those in the mining sector fare the...

Don't Trust Your Gut Summary The Numbers on Raising Children

In addition to finding love and success, many people dream of starting a family, yet once they have children, many worry that they’re doing too much or too little to raise them right. However, Stephens-Davidowitz says that statistical studies on parenting methods reveal something unexpected—that most of the parenting choices people make have very little impact on their children’s development. Nevertheless, there are two exceptions that do have a measurable impact on children’s success as they grow up—where you choose to raise them and, if they have athletic aspirations, which sports you help steer them to.

(Shortform note: In Cribsheet, Emily Oster adds a point of nuance to Stephens-Davidowitz’s claim that parenting decisions have little impact, based on research data. She says that the problem with parenting research is that it’s hard to design studies in a way that shows causality, which makes their results difficult to translate into actionable advice. As an alternative, she suggests that you [use economic...

Don't Trust Your Gut Summary The Numbers on Being Happy

So far, all the parts of life we’ve covered—love, success, and parenting—reflect an even larger goal—the desire to simply be happy. Once again, Stephens-Davidowitz argues that big data can offer a guide to happiness by correlating what people do and how they feel on a massive scale. He finds that certain behaviors tend to bring us down while others objectively improve our spirits, suggesting that the path to happiness isn’t that complicated at all.

In this case, the data Stephens-Davidowitz refers to comes primarily from the Mappiness smartphone app, which prompted millions of willing participants to record their daily activities as well as their emotional states. The result was a gigantic pool of information that data scientists have been able to mine so they can answer, scientifically, how to be happy.

(Shortform note: The happiness data collected by Mappiness is 100% self-reported, but while Stephens-Davidowitz accepts it at face value, other researchers question to what degree people can accurately measure their mood. For instance, Gallup polling data shows that women report higher levels of overall happiness than men, but [when asked...

Shortform Exercise: Put the Numbers to Work

Stephens-Davidowitz contends that we can use the results of “big data” analyses to improve our life choices. Odds are, you’ve already made many of the life decisions he talks about without the benefit of hard statistics. However, there are always more decisions to be made. Consider how you might rethink your approach to one or more of the aspects of life Stephens-Davidowitz discusses.

If you’re looking for a romantic partner, in what way could you widen your criteria for what type of person you’re looking for, based on the data that most “attractive” traits aren’t relevant to relationship success? In what way could you scientifically make yourself appear more attractive?