Early life on Earth: Tracing the chemical path from non-living to living

Amongst the most tantalizing questions in science are those relating to the life issue. What is it, how did it emerge, does it exist beyond our planet? In this review some central themes that have governed this debate over past decades will be described. Through the newly proposed Persistence Principle, it is argued that material stability can be achieved through either kinetic or thermodynamic means, opening up the possibility for life to be understood as a kinetic, rather than a thermodynamic, phenomenon. That insight allows the evolutionary process from inanimate to animate to be understood as one that was initiated with the emergence of a kinetically stable prebiotic replicative chemical system. Such a chemical system, once established, was able to evolve and complexify toward increasingly stable replicative forms, toward life. With a clearer understanding of what life is, the search for life in the universe can become more clearly directed.