NOTE FOR 2019 READERS: This is the sixth in a series of open letters to the next century. The series marks a little-known chronological milestone. According to UN data, life expectancy at birth in 27 countries now exceeds 81 years — meaning babies born in 2019 are more likely than not to see the year 2100.
What will the world be like at the other end of our kids' lives? Today's scientific discoveries, Silicon Valley visions, and science fiction can give us glimpses. But in this series of digital time capsules, we also recognize that our hopes and fears can shape what the future will become.