, , and also translated as , or , is a Japanese idiom for the awareness of , or transience of things, and both a transient gentle sadness (or wistfulness) at their passing as well as a longer, deeper gentle sadness about this state being the reality of life. Origins and analysis The idiom comes from Heian period literature, but was picked up and used by 18th century Edo period Japanese cultural scholar Motoori Norinaga in his literary criticism of The Tale of Genji, and later to other germinal Japanese works including the . It became central to his philosophy of literature; he saw it as the main theme of The Tale of Genji. His articulation was the result of well-established poetic readings of The Tale of Genji and the concept became central to his own; Genji was "instrumental" in the term's establishment. According to Norinaga, to "know" is to have a shrewd understanding and consideration of reality and the assortment of occurrences present; to be affected by and appreciate the beauty of cherry blossoms was an example of this knowledge provided by Norinaga. Japanese cultural scholar Kazumitsu Kato wrote that understanding in the Heian period was "almost a necessity for a learned man in aristocratic society", a time when it was a prominent concept. Donald Richie wrote that the term has "a near-Buddhistic insistence upon recognition of the eternal flux of life upon this earth. This is the authentic Japanese attitude toward death and disaster". Various other scholars have discussed the term. Etymology The phrase is derived from the Japanese word , which means , and , which was a Heian period expression of measured surprise (similar to or ), translating roughly as , , , , or . has seen multiple translations, such as and ; the Latin phrase has also been invoked. Awareness of the transience of all things heightens appreciation of their beauty, and evokes a gentle sadness at their passing. Norinaga saw the state of being as the fundamental condition of the concept. The term has seen gradual change in its meaning, although since "the beginning it represented a feeling of a special kind: 'not a powerful surge of passion, but an emotion containing a balance". In contemporary culture is "one of the most well-known concepts in traditional literary criticism in Japan". Yasunari Kawabata was a considerable modern proponent of . Norinaga asserted that the