Qualities that Basho valued in hokku (haiku)
Lightness - "karumi かるみ【軽み】 lightness, from karui (light)
Karumi- lightness or light-heartedness.
This does not mean "make light of something or anything".
It means to avoid sentimentalism or wallowing in emotions or taking things unduly seriously. It is the simple treatment of beauty to be found in ordinary things. It is simply to depict things as they are.
It is different from the court poetry.
It is minimalist, relying on terse concrete imagery and subtlety or lightness (as the shasei of Masaoka Shiki later on). [shasei means "a sketch from life]
"the beauty of ordinary things spoken of in a simple way.""Karumi was introduced by Matsuo Basho late in his life.
Karumi was the most notable characteristic of Basho's mature style. Karumi literally means a 'light beauty with subtlety' and was a quality Basho saw in higher levels of sabi. With karumi the loneliness of sabi opens into a contented acceptance.
When asked to describe karumi Basho said it was
"a shallow river over a sandy bed."(Info courtesy of Gabi Greve, used with permission)