public static Proposition createEquivalenceProposition(Stella_Object term1, Stella_Object term2) {
    { Proposition proposition = Logic.createProposition(Logic.SYM_LOGIC_EQUIVALENT, 2);
      Vector argumentsvector = proposition.arguments;

      (argumentsvector.theArray)[0] = term1;
      (argumentsvector.theArray)[1] = term2;
      return (proposition);
    }
  }