That differs from person to person, but my general experice is that the more of this world's education a person gets the less they seem to know. Some of it is a lack of common sense, some of it is the ever increasing trend towards specialization, and part of it is they are educated beyond their intelligence. The higher in the education system one goes the more narrow the field of view gets for them.
That being said, I have worked with a few highly educated people who were pretty sharp...and others who couldn't pour pee out of a boot with the instructions written on the heel...