Summa Metaphysica | David Birnbaum | 1-on-1 with Mark Davis Summa Metaphysica / David Birnbaum / 1-on-1 with Mark Davis / August 2016 1-on1 August 3 >> Back to MAIN video list for David Birnbaum philosophy, metaphysics, see also http://www.summametaphysica.com/newzealand-challenging/