Nothingness means no thingness, that is, pure being, pure process. pre-form, pre-manifest. The closest I've come to Nothingness is brief moments of being very much in the present with no attachment to thoughts, agendas, goals, or tasks. Such brief times have been experiences of intimacy such as while alone in meditation or in relationship with another. Such moments also occur when I am fully in the process of living and relating and not focused on outcome. Such moments are very alive. We are all rooted in Nothingness, though often not aware of it or respectful of it. Awareness of Nothingness, awareness of our rootedness in Nothingness, and brief experiences in Nothingness make for being in this world but not of it, and that awareness at least helps me stay rooted in awareness of Nothingness.