Mozart and Haydn were composing string quartets a quarter of a millennium ago, when the industrial revolution was in its infancy. Since then, the scale of the world economy has increased at least a hundredfold and material living standards in western Europe have grown 20 times over, perhaps more. Our ability to travel, build, calculate, communicate or simply produce food has been transformed beyond recognition. And yet the productivity of a live recital of Haydn’s Emperor quartet hasn’t budged: it still takes four musicians between 25 and 30 minutes to play.
250年前莫扎特(Mozart)和海頓(Haydn)創作弦樂四重奏時，工業革命處于早期發展階段。自那以后，世界經濟體量至少增長了100倍，西歐物質生活水平增長了20倍，也許更多。我們旅行、建造、計算、交流信息甚至只是制作食物的能力都發生了翻天覆地的變化。然而舉辦一場海頓皇帝四重奏(Emperor Quartet)現場演奏會的生產率絲毫沒有改變：仍然需要4名音樂家用25至30分鐘演奏。