As a special application of this operator, we next define the absolute umpire operator, also called the ''umpire measure''. This is a higher order proposition <math>\Upsilon_1 : (\mathbb{B}^2 \to \mathbb{B}) \to \mathbb{B}</math> which is given by the relation <math>\Upsilon_1 (f) = \Upsilon (1, f).\!</math> Here, the subscript 1 on the left and the argument 1 on the right both refer to the constant proposition <math>1 : \mathbb{B}^2 \to \mathbb{B}.</math> In most contexts where <math>\Upsilon_1\!</math> is actually applied the subscript 1 is safely omitted, since the number of arguments indicates which type of operator is intended. Thus, we have the following identities and equivalents: | As a special application of this operator, we next define the absolute umpire operator, also called the ''umpire measure''. This is a higher order proposition <math>\Upsilon_1 : (\mathbb{B}^2 \to \mathbb{B}) \to \mathbb{B}</math> which is given by the relation <math>\Upsilon_1 (f) = \Upsilon (1, f).\!</math> Here, the subscript 1 on the left and the argument 1 on the right both refer to the constant proposition <math>1 : \mathbb{B}^2 \to \mathbb{B}.</math> In most contexts where <math>\Upsilon_1\!</math> is actually applied the subscript 1 is safely omitted, since the number of arguments indicates which type of operator is intended. Thus, we have the following identities and equivalents: |