Researchers Studied Millions of Books Published Since 1820 to See What Makes Humans Happiest

Were people happier in 1800s than they are in the 2000s?

Perhaps literature could provide a clue to our happiness, as new research published in the journal Nature Human Behavior indicates. Based on the idea that what's captured in books can reflect the emotional state of people during the time the tome was written, researchers used the help of algorithms to look at millions of books, magazines, and newspaper articles published between 1820 and 2009. They used help from computers to analyze the words used in these books and evaluate the well-being of people in the United States, the United Kingdom, Germany, and Italy. For example, a word like "puppy" may be rated positively in terms of happiness, while the word "thief" may be rated negatively. This technique is known as sentiment analysis, and while it's not foolproof, it certainly revealed some interesting insights on happiness.

Among the fascinating findings? As Vox revealed in a recent article, one illuminating takeaway included, "Increases in national income do generate increases in national happiness, but it takes a huge rise to have a noticeable effect at the national level." Additionally, the study authors found that "an increase in longevity of one year had the same effect on happiness as a 4.3 percent increase in GDP." Even more of an impact on happiness than longevity? Living in a time of peace. "One less year of war had the equivalent effect on happiness as a 30 percent rise in GDP," summarizes the Vox article of the researchers' findings. Of course, this research only looked at a limited number of countries and since it analyzed books and not collected data on humans, it's difficult to make any sweeping statements, but it nonetheless gives us a sense of what conditions may inspire a more positive mental attitude.

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We wonder what our picks for five great new books to read this October say about our well-being.

For our next read, we think we'll pick an uplifting book, in the hopes that some of those positively-charged words can rub off on us.