expression
hindsight is 20-20 (even for a fool)
Rare expression meaning that even a fool can be wise after the event. Similar to 下種の後知恵.
See also: 下種の後知恵
「虚仮の後思案」ということわざがある。
There is a proverb: 'Even a fool has hindsight.'
A more common synonymous proverb with the same meaning.
The expression combines 虚仮 (fool) with 後思案 (hindsight). The exact origin is uncertain, but it is a traditional proverb.