Recent technological advancements encompassed under the Mobile Brain/Body Imaging (MoBI) framework, have produced exciting new experimental results linking mind, brain, and behavior. The main goal of the MoBI approach is to model brain and body dynamics during every-day, natural, real-life situations. However, even though considerable advances have been made in both hardware and software, technical and analytical conditions are not yet optimal. The MoBI approach is based on attaching synchronized, small, and lightweight neurobehavioral sensors to and around participants during behaviorally-measured structured, semi-structured, and unstructured settings. These sensors have yet to become fully unobtrusive or transparent. Even though a considerable technical and analytical gap still exists, acquisition of brain/body dynamics during real-world situations as well as in virtual, modified, and/or extended laboratory settings has been -in many cases- successful. Nevertheless, even if the technical/analytical gap is breached, novel hypotheses, measures, and experimental paradigms are needed in order to tackle MoBI’s ultimate goal: to model and understand cognition, behavior, and experience as it emerges and unfolds unto and from the world. Such a goal is not completely novel or unique to the MoBI framework; it is at the core of a long-standing scientific and philosophical challenge. The present work starts by briefly reviewing the historical origins of complexity in order to identify three “waves and ripples of complexity” derived from naturalist accounts to the historical brain/body problem. We furthermore argue for a current 4th wave. Finally, we offer the reader what we consider to be the main objective for the MoBI+4E framework in its quest for understanding the functional role of brain/body/world couplings in the emergence of cognition.