Definition of contraposition in English:

contraposition

noun

Logic
  • Conversion of a proposition from all A is B to all not-B is not-A.

    • ‘This means that form and content are not fully unified but retain a structure of abstract contraposition: the content is inscribed in the form while retaining much that cannot be grasped in it.’
    • ‘By contraposition and the definition of the existential quantifier, the latter axiom is equivalent to x = x y (y = x).’
    • ‘As a contraposition to the conclusions derived from the summation theorem, we have used similar mathematical tools to show that dominance is not an inevitable property of metabolic pathways.’

Origin

Mid 16th century: from late Latin contrapositio(n-), from the verb contraponere, from contra- ‘against’ + ponere ‘to place’.

Pronunciation

contraposition

/ˌkäntrəpəˈziSHən//ˌkɑntrəpəˈzɪʃən/