They have learned nothing, and forgotten nothing (and variations).

Recognized since the 19th century as a adoption, possibly used by Talleyrand, from a 1796 letter to Mallet du Pan by French naval officer Charles Louis Etienne, Chevalier de Panat: Personne n'est corrigé; personne n'a su ni rien oublier ni rien apprendre.—"Nobody has been corrected; no one has known to forget, nor yet to learn anything." Source: Craufurd Tate Ramage, Beautiful Thoughts from French and Italian Authors, E. Howell (1866)