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What You'll Wish You'd Known by Paul Graham
"(I wrote this talk for a high school.  I never actually
gave it, because the school authorities vetoed the plan to invite me.)

When I said I was speaking at a high school, my friends were curious.
What will you say to high school students?  So I asked them, what
do you wish someone had told you in high school?  Their answers
were remarkably similar.  So I'm going to tell you what we all wish
someone had told us.

I'll start by telling you something you don't have to know in high
school: what you want to do with your life.  People are always
asking you this, so you think you're supposed to have an answer.
But adults ask this mainly as a conversation starter.   They want
to know what sort of person you are...."
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