The Sun (Symbol)
The Sun is a powerful symbol of health and power. In the novel, many of the novel's robots are solar-powered and are only able to function because of the power of the sun. Without it, they wouldn't be able to enact their influence on the world.
Cootings Machine (Symbol)
The Cootings Machines throughout the novel, which block the rays from the sun hitting the earth, are symbols of death and destruction. Not only do these machines block out the sun's rays, they kill everything that depends on the rays, including humans and robots. They are the embodiment of the potential pitfalls of technology, which now rules the world.
Illness (Motif)
Throughout the novel, several children, but most prominently Josie and Rick, suffer from illnesses that effect their quality of life. For instance, Rick has an intellectual disability (at least according the powers that be in the novel), limiting the quality of his life. The illnesses many of the characters in the novel face emphasize the dystopian nature of the environment described in the novel.
Climate Change (Allegory)
Klara and the Sun is an allegory warning against the dangers of climate change. In the novel, humanity has created machines that spews pollution out of its spouts and prevents the sun from shining down on the earth. These machines are analogues for the things humans do (like driving cars and manufacturing) that are human-created and damage the earth.
