Mono no aware (もののあわれ?), literally "the pathos of things", and also translated as "an empathy toward things", or "a sensitivity to ephemera", is a Japanese term for the awareness of impermanence (無常 mujō), 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. - Wikipedia
'Birds and Flowers of Spring and Summer' by Kano Eino Suntory Museum of Art