知しらぬは亭てい主しゅばかりなり

expression

the husband is always the last to know

Proverb meaning that a husband is often unaware of his wife's infidelity while others know. Used idiomatically to describe a situation where someone is oblivious to something obvious to everyone else.

• 近きん所じょの人ひとはみんな知しっているのに、彼かれだけが気きづいていない。まさに「知しらぬは亭てい主しゅばかりなり」だ。

  Everyone in the neighborhood knows, but he's the only one who hasn't noticed. It's exactly a case of 'the husband is always the last to know.'