From a Some Random Guy on the Internet with the handle DC Sunset, but I thought it was as clear as anything from Poor Richard. This is why pride is the chief of sins and the father of all others:
All is lost when a man’s first vice is a delusion of infallibility.
All other vices will then cascade through their lives, and they will be forced by the resultant cacophony to jam their fingers ever more forcefully into their ears.
Wise people realize the limits of their own knowledge and accept that new arguments must be confronted or compel a change of opinion. Fools have all the answers and brook no new questions.