Red blood cells carry oxygen to different parts of the body, while white blood cells help the body's immune system. People also have diverse functions. Thus, people are the life force of Ulysses. Without them, the text loses all meaning. Corpuscles derive their meaning for existence from the specific functions they perform, creating a hierarchy of functionality, in which certain cells are more essential for well-being than others.
People also organize themselves into such a hierarchy.
If there is one thing the body teaches us, however, it is that regardless of the hierarchy, every cell matters. Nature created every corpuscle with a specific and important function in mind. On human terms, we tend to forget this fact. Even though people create a hierarchy in society, every function matters. We would be lost without the people on the lowest rung of the ladder.