What is a "simple life"?

All of a sudden, it occurred to me that I really don't know what a "simple life" is. What is a "simple life"? First of all, as a linguistic aside, I will note that I specifically chose the wording "a simple life" and not " the simple life". Although I have often heard and seen people speak and write of the latter, I believe that there is not necessarily just one "simple" lifestyle in the universe,…