過ぎたるはなお及ばざるが如し

(すぎたるはなおおよばざるがごとし)

Japanese meaning

程度を過ぎることは、足りないのと同じでよくない。何事もほどほどがよいとの教え。

English meaning

Excess is equivalent to deficiency.

Literal English translation

Too much is as bad as too little.