"History is the lie commonly agreed upon."

Voltaire meant by this quote is that history is transformed into a series of lies that people blindly agree upon. These lies are made in order to cover up bits of history that do not sound wonderful or heroic. Parts of history are just left out of our textbooks and ignored to make our country and other countries sound better. It is agreed upon because few people do not know the real truth behind our history. Since various other parts are also never talked about, the lies are continued to be spread.