Metamath Proof Explorer


Theorem mirimanofff

Description: Mirimanoff's paradox mirimanoff for founded sets. A set x is founded if every set containing x has a minimal element under membership. Compare with zfreg the defining condition of M in the hypothesis. (Contributed by Adrian Ducourtial, 28-Oct-2026)

Ref Expression
Hypothesis mirimanofff.1
|- M = { x | A. y ( x e. y -> E. z e. y ( z i^i y ) = (/) ) }
Assertion mirimanofff
|- M e/ _V

Proof

Step Hyp Ref Expression
1 mirimanofff.1
 |-  M = { x | A. y ( x e. y -> E. z e. y ( z i^i y ) = (/) ) }
2 rabab
 |-  { x e. _V | A. y ( x e. y -> E. z e. y ( z i^i y ) = (/) ) } = { x | A. y ( x e. y -> E. z e. y ( z i^i y ) = (/) ) }
3 1 2 eqtr4i
 |-  M = { x e. _V | A. y ( x e. y -> E. z e. y ( z i^i y ) = (/) ) }
4 3 mirimanofffr
 |-  M e/ _V