The society Lowry depicts in this novel is one of complete conformity. Every citizen knows his or her role, complies with the society's expectations in all things, and has no opportunity for individual expression. Rituals such as Ceremonies at specific ages regulate every aspect of life, including the very personal such as sex and death.
A "politically correct" citizen, then, is simply one who conforms. The novel traces Jonas' development from a typical conformer to that of questioner, and finally, rebel. He learns through his training with the Giver that to see colors, hear music, feel love and desire, and most importantly, to save the infant Gabriel from Release (euthanasia for lack of conformity), he ultimately must leave the society for the unknown.