There are various reasons why Atwood would emphasise the theme of chaos vs order. In the novel, she depicts a totalitarian government, and in theory, totalitarianism means the authorities have total control over the people in the country, its economy, etc. These societies are extremely orderly, and to show this, Atwood creates images of complete order. She builds a contrast to this by showing psychological chaos, and thus portrays how even though on the outside, everything is orderly, it still has negative psychological effects on people.