In this concept paper, we advocate for a paradigm shift in computational modeling. Advanced modeling should conceive new computational languages and models to describe real-life phenomena and solve real-life problems. Moreover, it should also be used to create "negotiated realities". A negotiated reality is an operating environment that situates within the reality-virtuality continuum. To model an environment, both the modeler and the users of the model are required: (i) to use a formal language for describing and explaining the functions and behaviors of a phenomenon and its environment, and (ii) to use the power of information technologies to search and experiment with new environments that would best address the problem at hand. We suggest an integrative formal language that includes an unbounded set of formal sublanguages to support the modeling of cognitive and reasoning situations, and an agent-based carrier sublanguage to offer the infrastructure required to support interactions in the virtual environment.