– you have to buy new books to get new information, an ongoing and expensive activity
– your books don’t update, and you have no real way of knowing when any bit of a book is out of date
– you have no good means of choosing which books to buy; you can handle your local bookstore, but the thought of a library with a trillion books is frightening
– you have no way of knowing whether something in a book is true or false
– you have no way to move beyond ‘book learning’, and nothing in the book tells you when you should do something (your actions are underdetermined by your knowledge; should you believe the sceptic, who says there is no floor, or the alarmist, who says the building is on fire?)
– you can’t develop skills; despite reading all about ‘bicycle riding’ you still fall over
You need, in other words, need to acquire facts in a format appropriate to your knowledge system.