From my new book. Coming very soon.
Stage 0 I would say is when you first sit down to meditate. The mind is cluttered with thoughts and impulses initially, distractions appear in the mind once you try to meditate. You feel hungry, perhaps worry that you haven’t turned off a tap somewhere in the house, or that you would be better off doing this at another time. If you persist with focussing on nothing you will reach stage 1.