The application of the principles of thermodynamics and General Systems Theory is responsible for important progress in the study of soil and its fertility, and this application can even improve our understanding of the processes that govern the functioning of soil and determine the magnitude of soil fertility. Consequently, we can improve the evaluation and practices recommended for preserving or improving the soil and its fertility, contributing to sustainable food production. Recalling how the concept and human perception of soil have evolved is fundamental to improve our understanding. Thus, this article aims to encourage people to reflect on the application of the principles of thermodynamics of non-equilibrium and General Systems Theory in studying the soil and its fertility and to participate in constructing a new notion of soil fertility, able to express what is perceived by plants. Several authors in the last century have considered the soil to be an open system; however, this approach is a recent in Brazil. Fertility can be coherently understood as one of the emergent properties of the soil system by applying the principles of thermodynamics of non-equilibrium and General Systems Theory to the study of soil.