Why is there something rather than nothing?

G.W. Leibniz is great for many reasons. For example, he invented the calculus independent of Newton. He is also a renowned philosopher. In particular, Leibniz put the question "Why is there something rather than nothing?" on the philosophical agenda. Some regard this as the ultimate question -- the biggest BIG question. Others find it futile. For example, Carl Hempel wrote:

"Why is there anything at all, rather than nothing?... But what kind of answer could be appropriate? What seems to be wanted is an explanatory account which does not assume the existence of something or other. But such an account, I would submit, is a logical impossibility. For generally, the question 'Why is it the case that A?' is answered by 'Because B is the case'.... An answer to our riddle which made no assumptions about the existence of anything cannot possibly provide adequate grounds... The riddle has been constructed in a manner that makes an answer logically impossible."

Hempel's argument is this: The existence of a thing X must inhere in the existence of some other thing Y. In other words, things can only originate from things. If we assume this to be true, then Hempel is right -- there is no logical answer to Leibniz' riddle. But why should we assume the principle that things only originate from things? Imagine that not a single thing existed. Wouldn't this be a fact? That is, wouldn't it be a fact that not a single thing existed? Isn't that enough to show that facts and things are not the same? Isn't that enough to show that not all facts are thing-dependent? If we want to answer Leibniz' riddle, we do not have recourse to things; but that does not mean we do not have recourse to facts. If we have recourse to facts, then Hempel might be wrong. There might be a logical answer to Leibniz' riddle after all.