Okay so the question at hand is to describe this statement using set theory and possible from logic.
Everybody is friends with everybody
My answer would be for this:
∀x∈S |{z∈S, f(x,x,z)}| = |S|
however could someone clarify if this is the same as saying
∀x∈S |{z∈S, f(x,z,z)}| = |S|
If not, could you please explain the difference .
Thank you,