In Chapter 23, Poem 45 of Attar's Mokhtar Nameh, the poet expresses a profound sense of existential futility and regret over the rapid passage of life. The poem employs the metaphor of the inverted sky as a millstone to describe fate relentlessly grinding down human existence. It emphasizes the sorrow that a lifetime passes in the blink of an eye, leaving one unfulfilled and ultimately returning to non-existence.