In One Flew Over the Cuckoo's Nest, there is the examination of man's struggle for individual freedom and the establishment of his sanity.
Statement #1 Man must struggle for his individuality in a conformist society that suppresses personal expression as a means of maintaining order.
In his essay "Self-Reliance," Ralph Walso Emerson writes,
Society everywhere is in conspiracy against the manhood of every one of its members. Society is a joint-stock company in which the members agree for the better securing of his bread to each shareholder, to surrender the liberty and culture of the eater.
Kesey concurs with this judgment of society, for in his novel the authority of society, represented by the "Big Nurse," dehumanizes the men in the ward. Alienated from other Native Americans, Bromden withdraws into feigned deafness and the "fog" rather than be subjected to her dominance. Harding, who has willingly committed himself further "surrenders his liberty" by allowing Nurse Ratched to make him "rabbit-souled" and intimidate, humiliate, and institutionalize him.
Statement #2 One man's sanity may differ from that of another; there is no single definition for self-realization.
In one of her insightful poems, Emily Dickinson writes,
Much Madness is divinest Sense -To a discerning Eye -Much Sense - the starkest Madness -’Tis the MajorityIn this, as all, prevail -Assent - and you are sane -Demur - you’re straightway dangerous -And handled with a Chain -