What is Life?

Life is defined as condition that distinguishes animals and plants from inorganic matter, including the capacity for growth, reproduction, functional activity, and continual change 

preceding death.  Do you agree with this definition?  I'm not quite sure I agree.  Initially, when I think of life, I think of humans and animals, and maybe even plants.  I have to the tendency to relate life with the ability to breathe; however, life is so much more complex than that.  I believe that viruses are alive, hence the term "live viruses" :) However, I truly believe life is relative.  Everyone is going to have a different definition for life so it's difficult to put a concrete explanation as to what life is.