If you're told not to lick metal poles in the winter time because your tongue will get stuck, you'll either respond with "okay, I won't" or "I doubt that would happen to me"
(I tripple dog dare you!!). But until you experience it, you'll never have a full understanding of what it's like to have your tongue stuck to a pole.
Street smarts are generally gained through personal experience, while complicated mathematics usually need to be explained. So it really depends on what is being learned, but I think it's best to have both. It's one thing to know something, but another to really understand it.