Passion itself is not the emotion, it is a state before which it out-pours and it is an excuse used by temperamentals like Melo the world over. I haven't confused what he is because what Felipe Melo brings to the table is an intense player, indeed so, but one that is not in control of his emotions, which must negate him being passionate I would think.
But I'm not a neuroscientist and we're talking semantics here. The boy is a rageoholic.