The exact scientific answer to these ancient questions are indispensable preconditions for the understanding of the origins of life, for the artificial synthesis of living systems, but also for some important social problems, such as the beginning and the end of the human life etc.Professor Gánti offers a radically novel approach to the problem: based on his theory of fluid (chemical) automata he proves that all living systems are basically program controlled self-reproducing fluid automata and that such automata behave as living systems. The simplest such construction-the chemoton-behaves as living, and all living systems have chemoton type organisation. This means that the chemoton model is the minimum model of life. The technical details have been published elsewhere: in this volume the logical train of though is presented in a clear and easily understandable manner. The first part gives a general view of the idea; the second shows its application to the biogenesis, the third gives the background of the theory in the natural philosophy of sciences.Gánti's chemical perspective captures the fundamentally cyclic organization of the living state, offers a fresh approach to the ancient problem of life criteria", and articulates a philosophy of the units of life applicable to genetics, chemistry, evolutionary biology, and exact theoretical biology"New essays by Eörs Szathmáry and James Griesemer on the biological and philosophical significance of Gánti's work indicate its enduring theoretical significance, continuing relevance and heuristic power. New notes throughout the text bring this legacy into dialogue with current thought in biology and philosophy.