
theorem :: Corollary 1.5.8
  for I being BinOp of [.0,1.],
      N being Fuzzy_Negation st
    I is N-satisfying_CP satisfying_(I1) satisfying_(NP) holds
      I in FI & FNegation I = N & N is negation-strong
  proof
    let I be BinOp of [.0,1.],
        N be Fuzzy_Negation;
    assume
A1: I is N-satisfying_CP satisfying_(I1) satisfying_(NP);
A4: I is satisfying_(I2) by A1,Corr157i;
    I is satisfying_(I3) by A1,Lemma154vb;
    hence I in FI by A1,A4,FUZIMPL1:def 15;
    thus FNegation I = N by A1,Lemma154va;
    hence thesis by A1,Lemma154va;
  end;
