In this chapter, we delve deeper into the life of Winston Smith and his role at the Ministry of Truth. Winston’s job primarily involves the alteration of historical records, a task that epitomizes the Party's manipulation of reality. Each day, he is tasked with correcting past newspaper articles and documents to ensure that they align with the current narrative dictated by the Party. This includes changing names, dates, and events to erase any inconsistencies or contradictions that may threaten the Party’s authority.

Winston reflects on the implications of his work, understanding that he is a cog in a massive machine designed to keep the populace in ignorance. The Party’s slogan, "Who controls the past controls the future; who controls the present controls the past," resonates strongly with him as he recognizes the profound power the Party holds over truth and memory. The concept of ‘doublethink’ is introduced here, highlighting the cognitive dissonance that Party members must adopt to reconcile their actions with the Party’s ever-shifting truths.

While performing his duties, Winston feels a growing sense of unease and guilt. He begins to understand that the act of rewriting history is not just a job but a deeply immoral act that contributes to the oppression of the people. He becomes increasingly aware of the loss of authenticity in life due to the Party’s relentless control over information. The manipulation of truth and memory leads to a society that can no longer trust its own past, creating a populace that is easier to control.

Winston’s reflections also lead him to ponder the concept of reality itself. He grapples with the idea that if the Party can alter the past, then what does it mean for the present and future? This existential crisis underscores his internal conflict and growing dissent against the Party’s ideology.

As he navigates through the archives filled with old newspapers and records, he feels a pang of nostalgia for a time before the Party's absolute control. This chapter serves to illustrate Winston’s increasing awareness of the Party’s oppressive nature and his own complicity in it, setting the stage for his eventual rebellion. Ultimately, Chapter 4 is pivotal in establishing the theme of the manipulation of truth—an essential element of the Party's totalitarian regime that deeply affects the individual and collective identity of society.