I'm a ki agnostic, myself. I don't know if it exists, I don't need for it to exist, I don't need to prove that it doesn't exist, I don't need to get into a debate with every person who uses the word "ki" to mean something that I think can be described quite well with more prosaic terms. Seems like too much wasted energy all around.
Well, I don't get into debates, either. I just smile and nod. But since my blog is all about me, I'm laying my feelings on the subject all out here.