posted by john .
how can the social, political or economic conditions alter the nature and meaning of art
It seems that LOTS of people are asking the same question online!
You need to examine the lives of some artists. Here are a few to consider:
Giotti - http://en.wikipedia.org/wiki/Giotto_di_Bondone
Leonardo da Vinci - http://en.wikipedia.org/wiki/Da_vinci
Michelangelo Buonarotti - http://en.wikipedia.org/wiki/Michelangelo
Questions to ask yourself -- How were Medieval influences at work in Giotti's works? How did artists and their works change with the coming of the Renaissance?
Wilfred Owen - http://en.wikipedia.org/wiki/Wilfred_owen
Ernest Hemingway - http://en.wikipedia.org/wiki/Ernest_Hemingway
How did wars or the lack of wars affect what writers wrote about and/or how they wrote?
Keep asking questions. Think of different time periods with identifiable social, political, and economic differences -- and explore the different artists' works who lived during those time periods.
In order to answer your own question, you not only have to know about the artists; you also need to understand the times in which they lived.
The meaning of Wagners operas has certainly been altered for me.