The 'one' element for scalar-quantites or the identity element with respect to multiplication. This element is unique and common to all scalar-quantities regardless of associated physical dimension. Therefore this element is equal to the number 1. The axioms tell us that the product of any scalar-quantity x and the identity-scalar is x.
(Identity-Element-For Identity-Scalar * Scalar-Quantity) (= (Quantity.Dimension Identity-Scalar) Identity-Dimension)
(=> (And (Scalar-Quantity ?X) (Recip ?X ?Y)) (And (Scalar-Quantity ?Y) (Forall (?Dim) (=> (/= ?X (The-Zero-Scalar-For-Dimension ?Dim)) (= (* ?X ?Y) Identity-Scalar)))))