"Sophomore" It's two Greek words put together: Sophia (wisdom) and moros (moron). The Greeks used this for someone with knowledge but not much in the way of wisdom and experience. The first you can get from books and schools... the second often takes time and life.
Teens can be very smart, they can know a lot of stuff. And that include doing and saying what they have learned is good and right and helpful. And teens can be loving, caring, giving - in fact, I often think older people don't give them the credit they should for that. But all that doesn't necessarily equal wisdom. Wisdom can be a bit allusive to younger people (well, older ones too).
Wisdom is pretty hard to define. In a way, it's kind of like "street-smarts" - it's practical in nature, it has more to do with living than with facts. It's related more to maturity than to intelligence. And it's hard to teach in books or schools (although a truly smart person CAN learn wisdom from others - without having to experience it themselves).
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