Is it not true that fundamentally there is nothing fixed concerning good or bad? Rather, depending on the occasion, what is useful is good, and what is not useful is bad. Our art depends on the taste of the audience at a particular time and place and will be produced in response to the general taste of the time. Such is the Flower that is truly useful. Here, one kind of performance is appreciated; there, another sort is welcomed. The Flower must differ depending on the spirit of the audience. Which of these Flowers then represents the true one? The nature of the Flower truly depends on the occasion on which it will be employed.
from ‘Style and the Flower‘ (1418) On the Art of the Noh Drama: The Major Treatises of Zeami, English translation J. Thomas Rimer and Yamazaki Masakuzu, Princeton U. Press, 1984.