Living in an age of relativism, everyone is allowed to have an opinion that reflects their own perception of reality.
Even if they don't say so, humans are just things that give meaning to other things. The whole concept of living and having a relationship (from making love to a woman to taking a bite from an apple or sticking a cat in a box) to the world around us means that we project our reality and explanation of it upon it.
As I said, everyone is allowed an opinion. But that doesn't mean that I can't find some opinions stupid. Especially if you try to push its validity upon me.
So without further ado, I give you a nice beat poem by Tim Minchin, who brings this with such wit and eloquence that I can only hope to achieve some of his verbal mastery