Talk to someone who's never done it before about what you want to do and they'll tell you why you can't do it.
All the adults who taught these things (reasons why you can't) were "people who have never done it before" who had never built an airplane or a rocket, and they were just saying the right things. If you talk to "People who have never done it before" about want to do, they will just tell you "Reasons why you can't", so this is just the wrong person to talk to. ---
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