<p>The growing interest in astrobiology renewed the enthusiasm of contemporary scholars to explore the Earth Systems Science theories of the twentieth century and scholars who influenced the later development of astrobiology. Vladimir I. Vernadsky seems to be recognized as one such scholar. In this paper, I provide an analysis of one such theory, Vladimir I. Vernadsky’s theory of the biosphere, and explore his conception of evolution in nature. I begin my research with the presentation of Vernadsky’s conceptual framework by explaining the meaning of the term “biosphere” and identifying the fundamental assumptions of his holistic theory. Next, I turn to the analysis of the concepts of living and inert matter, questioning their distinction and mutual relations. Whilst the differences between living and inert matter should enable us to demarcate these two domains of the biosphere and distinguish them at the ontological and conceptual levels, it seems that such an objective remains unattainable for Vernadsky. I find the reason for this conclusion in Vernadsky’s endorsement of a specific relation of reciprocal causality between living and inert matter. As I show, the relation of reciprocal causality emphasises the causal activity of the living matter and unifies it with the inert matter of the biosphere, leading to the unique conception of the common evolution of the living and inert matter, i.e., the evolution of the biosphere. However, Vernadsky’s synthesis of living and inert matter causes certain difficulties in the theory, reflected in our inability to clearly differentiate between living and inert matter at the ontological and conceptual levels.</p>