is a [explanation-seeking] Why-Question. [It is worth noting that the grammatically interrogative form of words 'Why is there anything at all?' could be used simply to express wonder that anything at all should exist, and not as a demand for an explanation.] Therefore, it invites an explanation. What sort of explanation? Steve M. holds two theses about this last question:
explanations that could be even relevant to explain Why-CCBs?
basis on which Bill and Steven challenge MII? They maintain that even if we assume that an adequate empirical explanation is offered (i.e., MI is satisfied) to each and every CCB, there is something else left over to explain. What is that “something else” that is left over that needs explaining (Steve M. asks)?
needs to be advanced into a new metaphysical realm.
His answer is this: what is left over after all empirical explanations favored by Steve M. are assumed to have been given is a very general property, feature, or aspect that all CCBs, and only CCBs, have in common. So why shouldn't ‘Why-CCBs’ questions be understood as inquiring into an explanation of this general feature that all and only CCBs share? Call this alleged general feature ‘X’.
that there is any phenomenon described by X that was not already accounted for by his favorite empirical explanations. Bill and Steven tried to articulate the content of X without (apparently) noticing that every such effort was rebutted by Steve M. either by appealing to the semantic thesis or to the explanatory thesis or both.
property of *is a contingent being* is instantiated (or something along these lines). [I would put it this way: X is the being-instantiated of the property of being a contingent being.]
such as X. Why? Two reasons: first, the property *is a contingent being* is not a sortal property; second, the predicate ‘is a contingent being’ (or any of its variants) contains a dummy sortal and therefore it does not pick out a property (nor does it have an extension) in the absence of a specific background presupposition of a specific sortal substituend.