Ignorance...

As we all know ignorance is one of the negative parts from a character that we all hate. I've done some research over the internet and I found a reasonable definition of ignorance : Ignorance is lack of knowledge about a thing in a being capable of knowing. We must note that ignorance may precede, accompany, or follow an act of our will. From my point of view we find ignorance like a relief from something that pressure our intellect. We want to be ignorant. It is that a good thing ?
I don't know.
Let's start with a clear example. Today I was at work and it happen to be send out for field work together with a co-worker of mine. I really hate this guy. Being in this company for over 22 year he act like hi is the best and smart and intelligent surveyor from the north east hemisphere. I was trying so many times by now to prove the guy that he is ignorant and he's ignoring every piece of information that somebody else tries to give it to him.
Now my question is : should I use ignorance in order to protect myself from not becoming crazy ? Is this one of the good face of being ignorant ?
I assume everyone experienced this at one point and i would like to find some points of wiew from you.
B.