What are the motifs in The Seven Storey Mountain by Thomas Merton?

Death is a motif throughout this story. Sadly, Merton's story includes the death of almost every relative mentioned: his mother, his father, his brother, his grandparents, and his aunt. Of course, it's only natural that a man outlive his parents and grandparents, but the deaths of all three members of his immediate family come prematurely, at tragic ages.