The argument that the two parties should represent opposed ideals and policies, one, perhaps, of the Right and the other of the Left, is a foolish idea acceptable only to the doctrinaire and academic thinkers. Instead, the two parties should be almost identical, so that the American people can "throw the rascals out" at any election without leading to any profound or extreme shifts in policy.

- Carrol Quigley, Tragedy and Hope

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 - even encourage the more critical and dissident views. 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