“The lotus is the most beautiful flower, whose petals open one by one. But it will only grow in the mud. In order to grow and gain wisdom, first you must have the mud --- the obstacles of life and its suffering. ... The mud speaks of the common ground that humans share, no matter what our stations in life. ... Whether we have it all or we have nothing, we are all faced with the same obstacles: sadness, loss, illness, dying and death. If we are to strive as human beings to gain more wisdom, more kindness and more compassion, we must have the intention to grow as a lotus and open each petal one by one. ”

― Goldie Hawn

According to the text, what does the "mud" represent in the process of human growth?