Miss.Loquacious (a.k.a. my best friend with far too much estrogen): "What is going on HERE?"
Me: "they're putting up drywall-"
Miss.L:"NO YOU DINGLE BERRY! HEEEERE!"
ME: Looks at Mr.Hampster who is completely oblivious with his headphones on "OH! Nothing..."
Miss.L:" Nothing? Why not? MR.HAMPSTER!!! WHY IS THERE NOTHING?"
Mr.Hampster: "Oh it's not nothing it's DRYWALL."
Miss.L: "NOOOO! NOT THAT HEEERE!!!!" (makes an exageratted hand jesture and nearly knocks over the DRYWALL)
Mr.Hampster: "OHH!! Nothing."
Miss.L: "NOTHING? WHY NOTHING!?"
Me: "Because there's nothing."
Miss.L: "WHY is there nothing?"

I'd like to know the same thing Miss.L.
The easy way to think about it (one day at a time) is that there's nothing because there's nothing. Maybe, one day, I'll actually convice myself that there's nothing.