The average age of the ...

The average age of the world's great civilizations has been two hundred years. These nations have progressed through the following sequence: from bondage to spiritual faith, from spiritual faith to great courage, from courage to liberty, from liberty to abundance, from abundance to selfishness, from selfishness to complacency from complacency to apathy, from apathy to dependency, from dependency back to bondage.
 Alexander Fraser Tytler

Quotes from the same author

A democracy cannot exist as a permanent form of government. It can only exist until a majority of voters discover that they can vote themselves largess out of the public treasury.
 Alexander Fraser Tytler