I Just Want to Celebrate by Rare Earth is about a transformed, better world. The lyrics are about the world, life itself and how no matter how much you are let down or are going through a tough time to just keep on going and celebrate another day of living. The song continues to talk about how you cannot be bothered with trivial things and sorrow.
http://www.youtube.com/watch?v=QZsppOw2Mxk
Mercedes Benz by Janis Joplin is about how consumers tie material things and money to happiness. In the song she talks about how her friends all have Mercedes Benz and so since she has worked she must have the same things they have in order to be happy.
Jenien Lim