'Why is there this--why is there anything at all?' A little reflection shows that a satisfactory answer to this question would require an altogether different kind of explanation from familiar sorts. Would any sort manage to do? If so, would more than one? O'Connor will not try to answer these questions in a short talk (!).  Instead, he wants to lay the groundwork for pursuing them in a rigorous and creative fashion. After identifying a couple key assumptions that underlie either the question of existence itself or certain kinds of response to it, O'Connor will try to rebut a common objection to the enterprise of seeking an explanation of contingent reality, viz., that the enterprise is bankrupt since contingent reality, by definition as it were, precludes the possibility of complete explanation.