This view is, of course, absurd to a field ecologist attempting to assess the health of global coral reefs. So life involves some chemistry, a metabolism, based on uptake of some chemicals, either inorganic nutrients or carbon compounds from other life forms and an ability to reproduce. Freeman Dyson 1985. Origin of Life, Cambridge Uni. Cells isolating a biochemical reaction chamber.
Reproduction involves rupture and fission of the cell and then reclosure to form new cells.
Slow, somewhat haphazard forms, but definable as life. RNA controls metabolisms while DNA controls reproduction. Clearly on Earth, today, the latter is dominant. Mad-cow desease and kuru are caused by reproducing proteins that make use of host materials to reproduce chemically. Both depend on other organims to be counted as living, i.e. they do not fit into our definition of life without host materials.