The Man with the Red Eyes is a servant of IT. As an individual, he is rather vague. It can be explained through the fact that children could not look directly on him. Besides that, Charles Wallace could feel like the Man with the Red Eyes talked through him. The Man with the Red Eyes was also called the Prime Coordinator and was the voice of IT. Through the use of this image as a vague yet evil force, the author strengthens the difference between the Man with the Red Eyes and IT, who turns out to be particularly horrible while comparing them with each other. At the same time, the Man with the Red Eyes claims to have sacrificed himself to save the sinful population. This episode shows how free will defines virtue, and how without the freedom to be evil and do bad things, virtue cannot exist.
The Man with the Red Eyes in the Essays