Yes. He is saying that there is a boundary between the "acceptable" opinions in this world, so people think only those opinions exist and anything else is weird or stupid. That way, people believe that they are free when they aren't.
"THE SMART WAY TO KEEP PEOPLE PASSIVE AND OBEDIENT IS TO STRICTLY LIMIT THE SPECTRUM OF ACCEPTABLE OPINION, BUT ALLOW VERY LIVELY DEBATE WITHIN THAT SPECTRUM. THAT GIVES PEOPLE THE SENSE THAT THERE'S FREE THINKING GOING ON, WHILE ALL THE TIME THE PRESUPPOSITIONS OF THE SYSTEM ARE BEING REINFORCED BY THE LIMITS PUT ON THE RANGE OF THE DEBATE." ~NOAM CHOMSKY; Repost w/ addition by Tigger & Willy of Engish Literature post
