Aided by scientific research into what makes people happy, and with an index of the world’s countries ranked by self-reported happiness levels, Weiner travels around the globe to see how happiness looks in places at the top and at the bottom of the list.

He finds that happiness is often rooted in how connected a country is to other countries. Several countries, like the island of Iceland and remote and hard to access Bhutan, that isolate themselves from the rest of the world both geographically and through their ideas, are able to maintain a sense of happiness from an incredibly strong sense of communal culture and social bonds. On the other hand, countries built in ways that emphasize comparison with the outside world, like the poor European nation of Moldova and the resource-rich Qatar, find that the national fixation on money does not bring their populations much happiness.

Happiness is also rooted in the social bonds of a country’s people—something that has a lot to do with a county’s history and response to outsiders. India, a place that has traditionally absorbed at least some of the cultures and customs of invaders and visitors, thrives because of its diversity.