The Diamond Age by Neal Stephenson
p283
"Nell", the Constable continued, indicating through his tone of voice that the interview was concluding , "the difference between ignorant and educated people is that the latter know more facts. But that has nothing to do with whether they are stupid or intelligent. The difference between stupid and intelligent people - and this is true whether or not they are well-educated - is that intelligent people can handle subtlety. They are not baffled by ambiguous or even contradictory situations - in fact, they expect them and are apt to become suspicious when things seem overtly straightforward.
"In your Primer you have resources that will make you highly educated, but it will never make you intelligent. That comes from life. Your life up to this point has given you all the experience you need to be intelligent, but you have to think about those experiences. If you don't think about them you'll be psychologically unwell. If you do think about them you will become not only well educated but intelligent, and then a few years down the road, you will probably give me cause to wish that I were several decades younger"