Why does the clock strike 13 in 1984?

In George Orwell's "1984," the clock striking 13 symbolizes the distorted reality and pervasive control of the Party over truth and perception. It represents a world where the familiar has become strange and unsettling, signifying the alteration of time and normalcy. This serves to illustrate the theme of totalitarianism, where even the most basic elements of life are manipulated, reflecting the oppressive atmosphere in which the characters exist.