Life, of course, takes the processual aspect of existence through many tiers of structural hierarchy. Jeffrey Wicken said: “Living systems are processes rather than things, and their existences are contingent on steady throughputs of matter and energy.” Living, after all, is something one does. In this sense, the question “What is life?” is grammatically misguided, or it requires that one not forget that the word “Life” denotes an activity, not a thing. The carbon atoms in your body are not in any way different than the carbon atoms in a lump of coal, here on earth or anywhere else in the universe. The pattern of activity which the atoms composing your body engage in do not “make your body alive,” this pattern of activity is life.
The same reasoning extends straightforwardly to selfhood. A self is a process performed by an organism. “Organism” denotes a specific kind of relational closure of a set of material elements which Wicken called an "autocatalytic organization". Many other similar terms may be found in the philosophy of biology literature which endorses the organismal view of life as opposed to the “bundle of selfish genes” hypothesis. Nearly all of them are formulated in direct response to the Kantian challenge of demonstrating, from physical mechanisms, how an organization in which every part is jointly ends and means for its own production could spring into existence on its own. "Biology will never have its Newton, capable of explaining the existence of a single blade of grass," the old curmudgeon claimed. LOL rite? Cuz physics, duh.
So one pleasing consequence of the thermodynamic view of life is that it provides a physical basis for the concept of selfhood as the unified energy-processing activity of the organism. Organisms are unified selves because they were subsets of the more general and necessary network of prebiotic chemical cycles that were “selected,” in a purely physico-chemical search for stable, persistent patterns of entropy production capable of *draining* the input energy from whatever source (solar or geothermal) was driving the system into a non-equilibrium organization. As the reaction matrix spontaneously evolved into more heterogenous mixtures under the probabilistic drive to increase molecular diversity, and additionally as the density of organic matter increased to values capable of driving the formation of large scale structures which would randomly confine components with different chemical capacities, it gradually became more and more likely that a subset of the prebiotic matrix gained this property of causal closure.