It may be that I have stumbled upon an adequate description of life itself. These modest yet profound words trumpet an imminent paradigm shift in scientific, economic, and technological thinking. In the tradition of Schrodinger's classic What Is Life?, Kauffman's Investigations is an exploration of the very essence of life itself, with conclusions that radically undermine the scientific approaches on which modern science rests - the approaches of Newton, Boltzman, Bohr, and Einstein. Building on his pivotal ideas about order and evolution in complex life systems, Kauffman finds that classical science does not take into account that physical systems - such as people in a biosphere - effect their dynamic environments in addition to being affected by them. These systems act on their own behalf as autonomous agents, but what defines them as such? In other words, what is life? Kauffman supplies a novel answer that goes beyond traditional scientific thinking by defining and explaining autonomous agents and work in the contexts of thermodynamics and of information theory. Much of Investigations unpacks the progressively surprising implications of his definition.