The true spirit of delight, the exaltation, the sense of being more than Man, which is the touchstone of the highest excellence, is to be found in mathematics as surely as poetry.

青竹 云海 晨光 星夜 荷风 晴雪 秋山 听海 沙丘 森语 梅影 花野 听雨 晴窗 暮色 橘光