無為　自然 Mui 　Sizen 　老子の良く用いた言葉 The words often used by Lao Tzu, an ancient Chinese philosopher and writer of BC era in China. Both Mui & Sizen is Japanese pronunciation, and the words are often used in Japan.
Literal translation into English can be: People’s behaviour should be natural.
Connotation can be: The natural order of things is to live an uncomplicated life, unconstrained by a sticking sense of rigorousness.