 In the hunter-gatherer and in the agrarian economy, you didn't have job choice. You just had going from 8 to 10 to 12 to 14 years old and getting better at doing what mom and dad, grandma and grandpa and everybody else in your community had always done, and you would do that kind of work. The Industrial Revolution created economic specialization and job choice, and it was scary as heck from 1870 to 1890.