He spoke on contingency and on causality, but in my opinion, both concepts are misunderstood in Ontology. Causality and Contingency make sense within Spacetime, outside, what you have is a perfect correlation, an Order of events that is timeless. From there its easy to conclude that Everythingness is a brupt fact and that Nothingness BY DEFINITION excludes itself from existence, it is a contradictory concept. Not Being cannot be!
NO THING means, No Metaphysics, No Information, No God, No Laws of Physics, No Space, No Time, No Physics, No Matter No Antimatter, No Dark Matter, No Positive or Negative Energy, No Chemistry, No Bio-Chemistry, No Consciousness, No Robots (hardware or software), No Phenomena, No Noumena, NO EVENTS, on past, present, or future, nor parallel anything Multiverses! MORE Nothing destitute itself from existence as a concept, So Nothingness includes No NOTHINGNESS!!!