For me sunnata is most easily understood through the Buddhadasa systems:-
If we remove attachment to the 5 khandas, if we remove the I and mine from the 5 khandas, then we can experience sunnata, the fundamental Gaia, the life force that is Nature. In terms of the Buddhadasa systems, removing attachment to the 5 khandas (which are body and psyche) then we are left with self and sunnata. But the self builds up over the years by attaching to the 5 khandas, if we detach from the existing selves then all we are left with is sunnata – emptiness, as it says in the Tao te Ching the emptiness that is full.
Kabat-Zinn refers to this as an internal wisdom, something that is inside. He referred to this internal wisdom here.
But his answer to this one of Angela Davis’s questions is perhaps far more significant, here the internal wisdom is a guiding force for good. Their talk is discussed in detail here.
Now I have alluded that mindfulness is a loose cannon. Kabat-Zinn has been at great pains to talk about mindfulness meditation as being relational, yet fundamentally he predicates it on this internal wisdom. Whilst I feel details of what this internal wisdom is needs to be investigated as it is the primary factor and as it is the root of mindfulness meditation in Buddhism that Kabat-Zinn claims to have eschewed. However internal wisdom is not part of academia so he would probably not have gained acceptance by demanding that mindfulness meditation is predicated on an undefined internal wisdom.
Internal wisdom prevents the cannon from being loose. If an internal wisdom is recognised then when mindfulness meditation is practised and there is no sankharic agitation the mind is free to reach for the internal wisdom that will guide. I cannot imagine that internal wisdom would be a core part of the mindfulness training for corporate execs!! Nor for young students.
Blogs:- Ginsukapaapdee, Mandtao, Zandtao.