there's no fool like an old fool

Proverb

 * 1) If a person does not develop wisdom with age, then their foolishness is all the more obvious and shameful.

Translations

 * Arabic:
 * Catalan: a cent anys, coteta verda
 * Chinese:
 * Mandarin: 人老不中用, 老糊塗最糊塗, 老人做的蠢事最愚蠢, 人無愚於老而愚者
 * Dutch: hoe ouder hoe zotter
 * Finnish: vanhuus ei aina tuo viisautta
 * French: on fait des sottises à tout âge, il n'y a que les imbéciles qui ne changent pas d'avis
 * German:
 * Italian:
 * Japanese:
 * Korean:
 * Polish: stary, a głupi
 * Portuguese:
 * Russian: ста́рого пса но́вым фо́кусам не нау́чишь, нет ху́же дурака́, чем ста́рый дура́к
 * Spanish: la cabeza blanca y el seso por venir
 * Welsh: henach henach, ffolach ffolach