I never knew what I wanted to be (and still don't). It wouldn't have made any difference. I was too dumb to achieve anything.
You shouldn't say that! I want to apologize in advance if I'm overstepping my bonds or whatever, but I've found that people who believe that way aren't having an issue with their intelligence... but rather their confidence.
Oh, I remember back when I was young (really young, we're talking about kindergarten here), that all the boys wanted to be either a race car driver, a ninja or a top-secret agent. All the girls wanted to be models or singers. Given how many singers we have nowadays, I'd say that at least their children managed to live on their dream.