Here's why:
* The passage juxtaposes the idealized figure of "Prince Peace" with the harsh realities of the early 20th century. Prince Peace is a symbol of peace and harmony, while the context of the novel, "The Jungle," depicts the brutal and exploitative conditions of the Chicago meatpacking industry.
* The statement is inherently contradictory. The phrase "nineteen hundred years since Prince Peace was born on earth" implies a period of peace and progress. However, the conditions described in "The Jungle" directly contradict this expectation, highlighting the irony of the situation.
By employing this ironic statement, Sinclair criticizes the hypocrisy and injustices of the era, emphasizing the vast gap between the ideal and reality.