If everybody always lies to you, the consequence is not that you believe the lies, but rather that nobody believes anything any longer. This is because lies, by their very nature, have to be changed, and a lying government has constantly to rewrite its own history. On the receiving end you get not only one lie — a lie which you could go on for the rest of your days — but you get a great number of lies, depending on how the political wind blows. And a people that no longer can believe anything cannot make up its mind. It is deprived not only of its capacity to act but also of its capacity to think and to judge. And with such a people you can then do what you please.

Hannah Arendt (1906-1975) German-American philosopher, political theorist

Interview with Roger Errera (Oct 1973), The New York Review of Books (26 Oct 1978)
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