I think its latin for "thus it is proven" or something like that. Once again, I hit post and realized JUST too late that I did not quote the posting I was replying to. Argh. It was an awesome explanation, simple, step-by-step and inescapable. I belive you ended it with something like "If each statement is true, then the conclusion must be true. Show me where it is wrong." Compared to that, everything else on the thread was a distraction.
So, thanks again!