Nobody is born learned.
We all learn a lot of things when we make bigger, when we're little our brain isn't developed so we don't know a lot of thing in that time.
How time you live, you learn.
If you live your life, if you're curios about all kind of things, then you can learn a lot of things.
Who knows book has four eyes.
Almost all the smart peoples have glasses because their eyes will be defects because of reading and studying.