In an article on Bunyan lately published in the "Contemporary Review" - the only article on the subject worth reading on the subject I ever saw (yes, thank you, I am familiar with Macaulay's patronizing prattle about "The Pilgrim's Progress") etc.
All censorships exist to prevent anyone from challenging current conceptions and existing institutions. All progress is initiated by challenging current conceptions, and executed by supplanting existing institutions. Consequently, the first condition of progress is the removal of censorship.
Each little thing that we do passes into the great machine of life which may grind our virtues to powder and make them worthless, or transform our sins into elements of a new civilization, more marvelous and more splendid than any that has gone before.