Three blind men come across an elephant, and examine it to figure out what it is most like. One touches its leg and exclaims, "It is like a tree!" Another touches the tail, and shouts, "No no! It is like a snake!" The third touches its side and argues, "You are both wrong! It is like a wall." And they continue to quarrel.
This moral here is that people, particularly "experts" can be ignorant to their own views. Perspectives and the method of questioning always matter, because each of us is blind to something.
Another version of the parable goes like this:
Three elephants come across a man, and examine it to figure out what it is most like. One touches the man, and exclaims, "It is flat!" The others touch the man and agree, "Yes, it is flat."
Come on, that's hilarious!