Tibor Gánti and Robert Rosen: Contrasting approaches to the same problem

Of the various theories of life that appeared in the second half of the 20th century the chemoton of Tibor Gánti and the (M,R)-systems of Robert Rosen are among the most important, of which the former is rooted in chemical engineering and the latter is highly abstract. Despite apparent differences, in part due to very different ways of presenting them, these two approaches share some important characteristics: both are "closed to efficient causation", which means that they require nothing from their environment, and in particular not catalysts, apart from "food", or chemical species that allow for the production of energy. On the other hand Rosen insisted that a living organism cannot be regarded as a machine, whereas Gánti explicitly discussed its mechanical nature, and the enclosing boundary is explicitly created by the system itself in the chemoton, but is (at best) simply implicit in (M,R)-systems.