The existence of Nothing ostensibly requires no justification. It is the only phenomenon which is commonly considered to be essentially natural and intrinsically logical.

But just what IS Nothing?

The "void" of space isn't Nothing as in non-existent. Space may be non-material - i.e. it does not have the property of mass - but it occupies volume and anything which has a physical presence in the Universe exists. An infinite expanse of space devoid of matter requires no less logical justification than an infinite expanse of matter devoid of space.

Semantically, Nothing has two connotations :
Nothing_(L) (in logical terms) is the null set - represented by the symbol 'Ø'.
Nothing_(A) (in the abstract) is 'that which does not exist'.

But, 'that which does not exist' doesn't exist. It isn't the empty set. It's not a set at all.

To consider Nothing_(A) would be not to consider.
To perceive Nothing_(A) would be not to perceive.
To understand Nothing_(A) would be not to understand.

(Editors Note: If you think you understand the preceding sentence, please go back and re-read it until you are absolutely certain that you don't. Thank you.)

Imagine an inert, infinitesimal point in space - and then try to imagine that same point NOT in space. Logic and perception require definition. Nothing - in the abstract context - is undefined.

In quantitative analysis the set of null value - represented by the symbol 'Ø' - is neither positive nor negative. It is a special case of neutrality. That same neutrality applies to qualitative and spatial values as well.

That necessary but indefinite primordial element we call "nothing" is simply an abstract interpretation of ultimate neutrality - the natural equilibrium that pervades the structure of the Universe.