Prove two simple iset properties involving stability
Prove two simple iset properties involving stability

Prove that decidability implies stability and that
every formula of the form -. ph is stable.

Signed-off-by: David A. Wheeler <9ae72d22d8b894b865a7a496af4fab6320e6abb2@dwheeler.com>

metamath/set.mm,metamath/set.mm,metamath/set.mm