What is a Generation?

Last Updated: Jun. 7, 2012

During the Middle Ages, travelers reported an unusual custom among villagers in central France. Whenever an event of local importance occurred, the elders boxed the ears of a young child to make sure the child remembered that day—and event—all his or her life.

Like medieval French villagers, modern Americans carry deeply felt associations with what has happened at various points in their lives. We memorize public events (Pearl Harbor, the Kennedy and King assassinations, the Challenger explosion, 9/11) by remembering exactly what we were doing at the time. As we grow older, we realize that the sum total of such events has in many ways shaped who we are. Exactly how these major events shaped us has much to do with how old we were when they happened. This is how generations are formed: Historical events shape peer groups differently depending on the phase of life they occupy. In other words, generations are shaped by the intersecting tides of life and time.

At LifeCourse, we define a generation as the aggregate of all people born over a span of roughly twenty years, or about the length of one phase of life: childhood, young adulthood, midlife, and old age. We identify particular generations, from first birth year to last, by looking for cohort groups of this length that share three criteria. This three-fold definition synthesizes what we consider the best insights of two centuries of generational writers, from John Stuart Mill and August Compte to Karl Manheim and Ortega y Gassett.

  1. Members of a generation share an age location in history. They encounter key historical events and social trends while occupying the same phase of life. For example, the G.I. Generation, who came of age during a crisis era of depression and world war, were shaped very differently from their Boomer children, who came of age during an awakening era of values experimentation and youth rebellion.
  2. Because members of a generation are shaped in lasting ways by the eras they encounter as children and young adults, they also tend to share some common beliefs and behaviors, including basic attitudes about risk taking, culture and values, civic engagement, and family life.
  3. Aware of the experiences and traits they share with their peers, members of a generation tend to have a sense of common perceived membership in that generation. Numerous surveys have shown that most members of various generations identify themselves as a unique group with a different outlook from those outside their generation.

Most researchers focus on age brackets, as though the people in these brackets were constant and unchanging. We believe this approach is deeply misleading. People never “belong” to an age bracket. Rather, they belong to a generation that happens to be passing through an age bracket—a generation with its own memories, language, habits, beliefs, and life lessons.

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