Openness has two aspects: participative openness, being free to say what one thinks, and reflective openness, the willingness to challenge one's own thinking and hold every certainty as a hypothesis (the other person might be right and I might be mistaken), which rests on skills; participation without reflection produces stated views that change no one's thinking.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.