Traditionally, life has been divided into two main parts: a period of learning followed by a period of working. In the first part of life you built a stable identity and acquired personal and professional skills; in the second part of life you relied on your identity and skills to navigate the world, earn a living, and contribute to society. By 2040, this traditional model will become obsolete, and the only way for humans to stay in the game will be to keep learning throughout their lives and to reinvent themselves again and again.