What about on the beach? In a bathing suit? Could a 23 year old pass for 17 and vice versa?
The fact is that teenagers 16 and up look exactly like adult because they ARE adults. Puberty ended their childhood a few years prior.
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Discussion
In the 1970s it was totally normal for a tall young man, 16 years old, maybe bearded, to get into night clubs and bars simply because he "looked older"
Neo-puritans are desperate to draw some kind of line between teenagers and adults, but they have nothing to work with.
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