principles, the principle of maximum power efficiency, takes central place in the analysis and synthesis of ecological systems. The fourth principle suggests that the most evolutionarily advantageous system function occurs when the environmental load matches the internal resistance of the system. The further the environmental load is from matching the internal resistance, the further the system is away from its sustainable steady state. Therefore, the systems ecologist engages in a task of resistance and impedance matching in ecological engineering, just as the electronic engineer would do. Closely related fields Deep ecology Deep ecology is an ideology whose metaphysical underpinnings are deeply concerned with the science of ecology. The term was coined by Arne Naess, a Norwegian philosopher, Gandhian scholar, and environmental activist. He argues that the prevailing approach to environmental management is anthropocentric, and that the natural environment is not only "more complex than we imagine, it is more complex than we can imagine." Naess formulated deep ecology in 1973 at an environmental conference in Budapest. Joanna Macy, John Seed, and others developed Naess' thesis into a branch they called experiential deep ecology. Their efforts were motivated by a need they perceived for the development of an "ecological self", which views the human ego as an integrated part of a living system that encompasses the individual. They sought to transcend altruism with a deeper self-interest based on biospherical equality beyond human chauvinism. Earth systems engineering and management Earth systems engineering and management (ESEM) is a discipline used to analyze, design, engineer and manage complex environmental systems. It entails a wide range of subject areas including anthropology, engineering, environmental science, ethics and philosophy. At its core, ESEM looks to "rationally design and manage coupled human-natural systems in a highly integrated and ethical fashion" Ecological economics Ecological economics is a transdisciplinary field of academic research that addresses the dynamic and spatial interdependence between human economies and natural ecosystems. Ecological economics brings together and connects different disciplines, within the natural and social sciences but especially between these broad areas. As the name suggests, the field is made up of researchers with a background in economics and ecology. An important motivation for the emergence of ecological economics has been criticism on the assumptions and approaches of traditional (mainstream) environmental and resource economics. Ecological energetics Ecological energetics is the quantitative study of the flow of energy through ecological systems. It aims to uncover the principles