Sinclair uses the vast stockyards that are packed with animals for slaughter to represent a couple of ideas. The first is dehumanization. The stockyards are filled with animals that are ready for the slaughter with the next one ready to step up when the one before it is killed. There is a stunning regularity to the replaceable aspect of life in such a setting. Certainly, this is a way in which Sinclair is able to point out how capitalism is an economic system that stresses this element of "replaceability." For Sinclair, modern America is one where workers line up, packed in vast worklines, seeking work. When the work demands one of them, the next one is ready to take that place with a stunning regularity. For Sinclair, the livestock packed in the vast field ready for slaughter is akin to the vast number of workers, consolidated in modern cities in America. Both are used for the ends of the wealthy and powerful and when they have become expended, another steps up to continue the cycle of abuse. At the same time, the vast stockyards help to bring to light that this machine of production is in full overdrive, and will not correct itself. The machine of production, profit, and more production and more profit is only facilitated when there are enough resources to sustain itself. This is the exact condition of the vast stockyards and is also the state of capitalism, in general. For Sinclair, the idea of capitalism as a self- sustaining machine of dehumanization has to be evoked and brought out in order to bring to light its nature, and the eventual call to change it.