Hopefully this post won't be as vaccuous as the title implies...
The concept of nothingness has always been something I've struggled with. The way I used to explain it to prospective listeners during late night philosophical conversations is as follows:
"Imagine the universe. Generally people think of it as a spherical object. Now imagine what's outside that sphere. If you subscribe to some sort of multiversal theory, just go out as far as you can and imagine what's outside of that. If you've never thought about it before you're probably imagining blackness, but if you have, you're probably struggling to imagine anything at all, which is exactly what should be going on. Blackness doesn't even begin to cover 'nothing.' It's almost unimaginable. How do you visualize, or even idealize something as 'empty' as nothingness?"
The conversation almost never went farther than that... but I have, and I will here. It becomes even more complicated when you think about what nothingess truly means. To understand the word "existence" we need a concept of nothingness to juxtapose it to. Like I've said before, the universe is a relative place. The only way we understand something is by comparing it to something else. So what is existence? The property of not not-existing. But for nothing to... 'exist' (the only verb that comes close to describing it) there cannot be anything else in 'existence'... because... well, because then it wouldn't really be nothingness, now would it? Seems like a bit of a paradox, but we can always chalk it up to the fact that just because our minds require it, doesn't mean that nothingness has a manifestation in reality. It might only exist in our minds.