In George Orwell's dystopian novel 1984, it can be argued that the citizens of Oceania do not choose to be ignorant, but rather are manipulated into complicity by the INGSOC Party's propaganda machine.
For example, in the first chapter of the book, we are introduced to the official slogan of the Party:
WAR IS PEACE. FREEDOM IS SLAVERY. IGNORANCE IS STRENGTH.
Upon first glance, all three of these phrases appear to be contradictory. How can one argue that war is peace, or that freedom results in slavery? Ultimately, it is the third statement—"IGNORANCE IS STRENGTH"—that proves vital for Oceania's success. As even the act of thinking is considered a thought crime (making Oceania susceptible to outside attack by its enemies) the ignorance, or "not-knowing," of its people is essential for keeping the war and political machine intact. If it is unpatriotic to question the hypocrisy of the Party, then the Party can continue to use the people without any fear of critique.
Despite the ignorance encouraged by the government, it is important to note that Winston, our narrator, is aware of such inherent contradictions as early as the first chapter of the book. When Winston secretly decides to start a diary, he notes that "it was not illegal" to start one, because "nothing was illegal, as there no longer any laws"—but that he also knew that, if caught, the punishment would most likely be forced labor or death. The absence of law, in this case, does not cause lawlessness; it only causes confusion and uncertainty about what is right and what is wrong.
Without the freedom to interpret the laws for themselves, all the citizens of Oceania can do is to listen to their government, trusting that the government has their best interest in mind. As we continue reading 1984, however, we realize that this is certainly not the case.