This paper introduces the idea of actualizing theory in the context of artistic practice. We describe the project BodyDaemon and its function as a technology-based artwork that is an example of an actualized, physically manifested theoretical experiment. We label this theory as action. BodyDaemon is a techno-conceptual art project. It includes a server that is powered and configured by a participant’s physiological states and a protocol for exchanging bio/server data across the Internet. Noting that a body network cannot operate without a body, we seek to explore the body’s role with respect to information technologies and networks in particular. Our approach is to construct a form of tangible theoretical knowledge using networks, protocols, code and physiological monitoring as artistic materials. Keywords Interactive Art, Physiological Monitoring, Biofeedback, Body, Embodiment, Network, Protocol, XML, Cultural Theory, Reflective Design, First-person Methodologies.