I’ve been researching generational differences for 25 years, starting when I was a 22-year-old doctoral student in psychology. Typically, the characteristics that come to define a generation appear gradually, and along a continuum. Beliefs and behaviors that were already rising simply continue to do so. Millennials, for instance, are a highly individualistic generation, but individualism had been increasing since the Baby Boomers turned on, tuned in, and dropped out. I had grown accustomed to line graphs of trends that looked like modest hills and valleys. Then I began studying Athena’s generation.