wabi
... By the influence of Zen philosophy, Sen no Rikyu (A Great Tea Master), Introduced the concept of Wabi or elegant simplicity. Wabi is the Japanese sense of beauty of the imperfect, the impermanent, the incomplete, the modest, the humble, rustic and organic, a sense of beauty in the unconventional. Wabi is very simple and complex. ... The core of Wabi and Japanese life is transcending the way of "looking" and "thinking" about existence. Wabi and sabi are two concepts or guiding principles that have deeply influenced Japanese aesthetics and cultural life including architecture.