Nothingness

[Sal]

I find your lack of understanding of mathematical set theory disturbing.

j/k.

But really. In set theory, Ø, is quite literally lack of a number, and it is defined as {} by designation.

Somehow, you haven't explained how zero isn't nothing, though... are you considering it a difference of 'zero ____ is not a complete absence of things, only the absence of ____ thing(s), whereas nothingness is the void of any non-nothing things'?

When I was thirteen, I used that Ø symbol in a lot of character names

Quite right.

In my first post I made the distinction between zero into amount and Ø.

You can have for instance an amount of apples, say, 3 apples and give 3 apples away, you're still left with an amount, namely zero apples. This is a trivial but an important departure from The Empty Set. Where you can't say to have Ø of anything, i.e. you can't have Ø amount of something, or anything for that matter - because as soon as you say you have an amount of something, being it zero or even negative amount ("debt") then you have defined it and it becomes a part of existence.

The first part of your sentence that you use in your reply:

zero ____ is not a complete absence of things, only the absence of ____ thing(s), [...]

Is about amount, while:

whereas nothingness is the void of any non-nothing things'

is The Empty set, Ø.

The Empty Set is also used in logic, it's not just confined to mathematics.

AFAIK, The Empty Set is different from Division By Zero - which in standard math defies logical definition and to this day remains undefined. However, both Division By Zero and The Empty Set are two kinds of types of things that sorta designate lack of explanation and lack of something. Might be we get some brilliant logician and/or mathematician that can sufficiently explain DBZ without paradoxes.