Of course, a smartphone opens up worlds of new possible experiences, including video games (which are forms of play) and virtual long-distance friendships. But this happens at the cost of reducing the kinds of experiences humans evolved for and that they must have in abundance to become socially functional adults. It’s as if we gave our infants iPa

My central claim in this book is that these two trends—overprotection in the real world and underprotection in the virtual world—are the major reasons why children born after 1995 became the anxious generation.

When it was carried into schools in the early 2010s, on smartphones in students’ pockets, it quickly changed the culture for everyone. (Communication networks rapidly become more powerful as they grow.[16]) Students talked to each other less between classes, at recess, and at lunch, because they began to spend much of that time checking their phone