Digressing ring away to a simpler thing really,
Euler diagram:
Wikipedia wrote:Euler diagrams consist of simple closed curves (usually circles) in the plane that depict sets. [...] Venn diagrams are a more restrictive form of Euler diagrams. [...] When the number of sets grows beyond 3, or even with three sets, but under the allowance of more than two curves passing at the same point, we start seeing the appearance of multiple mathematically unique Venn diagrams.
I'm telling you, nothing is certain

You can't honestly find one thing made of two sets, unless if these sets are
me and
what remains
I am amazed at the polymorphism allowed by maths.