Upton Sinclair, (1878-1968), was an American writer and reformer. Sinclair was an idealistic supporter of socialism and became famous as a “muckraker”. The term muckraker according to wikipedia means “to reform-minded journalists who wrote largely for popular magazines and continued a tradition of investigate journalism reporting.” Muckrakers emerged in the United States in 1900 and was influential until World War I. In present day, the term Muckraker mean a journalist who writes in an alternative tradition, or a non-journalist whose purpose in publication is to advocate reform and change. The investigative journalists view the muckrakers as early influences.
Upton Sinclair hoped to illustrate the horrible effects of capitalism on workers in the Chicago meatpacking industry. The Jungle is about workers sacrificing their fingers and nails by working. The workers died because of diseases, acid, losing limbs, and toiling long hours in cold. They worked in terrible conditions. He hoped the public shout would be so fierce that reforms would soon follow.