The exact correspondence in first order language is as follows:
$∀x((x∈S ∧ x≠a) → ⋯)$
It reads: for all $x$, if $x$ belongs to $S$ and $x$ is not $a$, then....
$x≠a$ is just a short form for $(x=a)$
The exact correspondence in first order language is as follows:
$∀x((x∈S ∧ x≠a) → ⋯)$
It reads: for all $x$, if $x$ belongs to $S$ and $x$ is not $a$, then....
$x≠a$ is just a short form for $(x=a)$