What is the interpretation of ∅-∅?

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What is ∅-∅ equal to?
Logically this is represented as the set containing all x such that x[itex]\in[/itex]∅ and x[itex]\notin[/itex]∅. I am confused on how to interpret this...I think the answer would just be the null set, but I am not sure. Could someone please clarify this?
 
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Think of the subtraction of sets as the intersection of the one with the complement of the other. That is ∅[itex]\cap[/itex] ∅[itex]^{c}[/itex]
 
There is no ##x## for which ##x \in \emptyset## and ##x \notin \emptyset##, so there are no elements in ##\emptyset - \emptyset##.
 
Makes me think of the song quite a few years back, "Nothin' from nothin' leaves nothin." - Billy Preston, 1975
 
Mark44 said:
Makes me think of the song quite a few years back, "Nothin' from nothin' leaves nothin." - Billy Preston, 1975
Great post, Mark !
 
Aziza said:
What is ∅-∅ equal to?
Logically this is represented as the set containing all x such that x[itex]\in[/itex]∅ and x[itex]\notin[/itex]∅. I am confused on how to interpret this...I think the answer would just be the null set, but I am not sure. Could someone please clarify this?

That is exactly right. It may help to simplify that logical expression, because you can, for example, replace [itex]x \in \emptyset[/itex] with a truth value.

Or maybe slightly reorganizing it to the fact that

x is in ∅-∅​

is synonymous with

x[itex]\in[/itex]∅ and x[itex]\notin[/itex]∅​