Double negative would have found a more flattering way to say so. Instead, some kind of problem is implied, though Mr. Jones possesses basic competence at his tasks. Discussing English grammar, the term "double negative" is often though not universally applied to the non-standard use of a second negative as an intensifier to a negation. Double negatives are usually associated with regional and ethnical dialects such as Southern American English, African American Vernacular English, and various British regional dialects. Indeed, they were used in Middle English. Historically, Chaucer made extensive use of double, triple, and even quadruple negatives in his "Canterbury Tales".
Quadruple product Quadruple product In mathematics, the quadruple product is a product of four vectors in three-dimensional Euclidean space. The name "quadruple product" is used for two different products, the scalar-valued scalar quadruple product and the vector-valued vector quadruple product or vector product of four vectors . The scalar quadruple product is defined as the dot product of two cross products: where a, b, c, d are vectors in three-dimensional Euclidean space. It can be evaluated using the identity: or using the determinant: The vector quadruple product is defined as the cross product of two cross products: where a, b, c, d