Have you ever met someone who thinks they are smarter than everyone else in the civilized world?  These people tend to project an arrogance and pride that leaves you with, at best, dislike, or at worst, disgust for them personally or their agenda.  Some folks like to play the word game.  You know the type- they take the most accurate sentence and common interpretation of something and present it as false by adjusting a word or emphasis.  Semantics.  Again, the audience is left feeling frustrated.  This is not what an educator wants to achieve.  Learning will not take place in kind of environment.

Educators are expected to be fully knowledgeable in their fields but they are much better recieved when they present the material with humility.  All people have the capacity, and I would say, tendency to make errors.  While the know-it-all will try to play it off or manipulate the situation to appear right, the humble educator will admit their mistakes, correct them, and move on...and move on with the respect of their audience.  When the audience is made to feel inferior the tendency is to shut down and protect.  If an educator hopes to encourage growth and learning, the recipient must be open and ready to change.

This isn't scientific theory and I don't have any websites to support my claims (though I'm sure they exist) but I do have plenty of personal experience to know that the know-it-all personality really grates on my nerves.  Folks don't feel comfortable questioning a know-it-all.  Folks don't really trust that anyone can know it all so they doubt that the person knows anything at all.  Folks don't appreciate being made to feel inferior.  Educators won't be successful with this kind of mentality.  Find some humility and admit your deficit of knowledge.