I have always wondered why some generations are widely recognised to last ~15 years, others 18, some others 25. What even constitutes a generation?
In: Biology
Generations like boomers, X, millennials etc are mostly non scientific bullshit. So that’s why the duration are not the same or clearly defined. No science involved here.
Generations aren’t very strongly defined. The most common rule is 25 years makes a generation, from the idea that by that age most people will be having their own children. But often times generations are also used to express differences in the environment people grew up in. Those historical/cultural periods don’t fit neatly into 25 year periods, so generations in the sense of “the silent generation” and “gen z” tend not to follow that rule.
There’s no real, official definition of a generation. It’s more of a cultural phenomenon centered around large shifts in society and technology.
Is someone born in 1995 a millennial? They were only 5 on Y2K and barely remember it, but they do vaguely remember the young internet in a way someone born in 2001 might not. They’re right at the transition between two cultural moments.
In the same way, some “baby boomers” got drafted to fight in Vietnam and some were nine years old. They’re often tossed into the same “generation” but someone born in 1945 and someone born in 1959 had quite different experiences. Those late “boomers” were children during a cultural transition and it’s hard to place them.
Generations are artificial. We make them up because they describe rough social patterns. Their boundaries are always fuzzy and awkward, and often more defined by “were you alive to experience X” than anything else.
The 25-year figure is usually used more by genealogists and anthropologists, looking at the long span of human history. Most people have their first child somewhere between 20 and 25 in the modern world.
Generations are typically measured in the average length of time for a woman to mature and have a child. That is usually around 20 years
So there’s a major conflict on how generations are defined and how people use them. Originally you would have a generation defining event. These would be things like catastrophes, wars, inventions, changes in governments. Some time after WWII these events started happening pretty rapidly. You had Korea, the space race, the cold war, Vietnam, TV becoming mainstream, Civil Rights, Kennedy’s Assassination all in a 20 year span. Each one of these would historically be considered a generation defining event and they all happened in less than a single generation period. This continued to accelerate through to today where generational events are almost a yearly occurrence. In 2020 we saw Covid, 2021 saw a rover land on Mars, 2022 saw the birth of generative AI, 2023 Russia invades the Ukraine, 2024 hasn’t been quiet but hasn’t had what I would consider a unique event yet, but it’s an election year so something is bound to boil over between partisan politics.
Because generations are more strongly defined by events than duration. For example, the baby boom starts 1945 because that’s when soldiers came home from WWII. And Generation X starts 1961 because that’s when the birth rate started dropping following the release of the Pill in 1960.
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