Question: “Tommy, did you punch Billy in the face?” Response: “No, ma’am, honest, I didn’t.” Question: “Well, then, Tommy, what caused Billy’s black eye and bloody nose and concussion?” Response: “Nothing, ma’am, nothing at all. Those things just happened.” In all three cases, the explanation is clearly insufficient. “Nothing” cannot cause a black eye or the sudden appearance of $100 bills or a stray cat. Indeed, “nothing” cannot cause anything, because nothing is the absence of all things and therefore