It is not only simple beauty of form and color. Man can make that without making nature. It is not only fitness to purpose. Man can make that too, without making nature. And it is not only the spiritual quality of beautiful music or of a quiet mosque, that comes from faith. Man can make that too, without making nature. The quality which has no name includes these simpler sweeter qualities. But it is so ordinary as well, that it somehow reminds us of the passing of our life.
It is a slightly bitter quality.
Christopher Alexander in “The Timeless Way of Building” p. 39-40
A slightly bitter quality
