This Tagore poem links sadness with creation:
It is the pang of separation that spreads throughout the world
and gives birth to shapes innumerable in the infinite sky.
It is this sorrow of separation that gazes in silence all nightf
rom star to star and becomes lyric among rustling leaves in
rainy darkness of July.
It is this overspreading pain that deepens into loves and
desires, into sufferings and joys in human homes; and this it
is that ever melts and flows in songs through my poet's heart.
-Gitanjali #84, Rabindranath Tagore