Explain with reference to the context "The story of a poor man's life is written on his body, in a sharp pen."

The protagonist's letters are addressed to Chinese premier Wen Jiabao from Balram Halwai. Balram is referring to how a man's life is "written" on his body.

“A rich man’s body is like a premium cotton pillow, white and soft and blank. Ours are different. My father’s spine was a knotted rope…cuts and nicks and scars, like little whip marks in his flesh, ran down his chest and waist, reaching down below his hipbones into his buttocks. The story of a poor man’s life is written on his body, in a sharp pen.”

This illustrates the harsh life of a poor man in India.