The three doshas of Ayurveda and their five respective subdoshas are related to the modern scientific framework of systems theory, phase transitions, and irreversible thermodynamics. These empirically well-established concepts of Ayurveda then appear to be far more general biologic concepts than the neuroendocrinology of their functioning might imply. They express universal concepts applicable across living organisms-control structures governing living systems. The hypothesis that the 15 subdoshas can themselves be considered as 5 triplets implies that on the level of the whole organism, these secondary structures of control appeared at specific stages in the evolution of life, yielding new insights into their development and evolution. The description of varying states of health and disease given in Ayurvedic etiology is related to the format of phase transitions in irreversible thermodynamics.