Positing that organizational phenomena result from both individual human intentionality and natural causes independent of individuals' intended behavior, the need for a quasi-natural organization science is identified. The paradigm war is defined in terms of positivism and postpositivism, with the suggestion that a more relevant epistemology might be scientific realism. The current unconstructive paradigm proliferation is seen as resulting from an underlying cause, idiosyncratic organizational microstates, phenomena identified by postmodernists. The article develops quasi-natural organization science as an antidote to multiparadigmaticism by recognizing that mathematically, computationally, and experimentally intense twentieth century natural sciences all have microstate idiosyncrasy assumptions similar to those postmodernists suggest are true of organizational phenomena. By framing a quasi-natural organization science focusing on microstates, my intent is not to deny the relevance of either intentionality and subjectivity or natural science and objectivity. The article attacks the microstate idiosyncrasy problem on four frontiers: micro- and macroevolutionary theory, semantic conception epistemology, analytical mechanics, and complexity theory. The first frontier develops the natural side of quasi-natural organization science to explain natural pattern or order. This “order” arguably results from multilevel coevolutionary behavior in a selectionist competitive context in the form of multi-level selectionist effects. The second frontier reviews the historic role of idealized models, as understood by historical realists and the “semantic conception of theories”—idealized constructs such as point masses or the rational actor assumption—that currently successful sciences, such as physics and economics, drew upon early in their life-cycles to sidestep the idiosyncrasy problem. Organization scientists are encouraged to develop theories in terms of idealized models. The third frontier attends to the role of ‘instrumental conveniences’ as essential constructs in the early life-cycle stages of sciences and the importance of studying rates. For example, a construct such as a pressure vessel acts as a container translating idiosyncratic gas particle movements into a directed pressure stream where particles emerge at some rate. Drawing on Sommerhoff's “directive correlation” concept as an analogous “container” in firms, this section argues that such containers can be used in organizational analysis to translate idiosyncratic microstates into probabilistic rates of occurrence, thereby allowing the use of intrafirm rate models and Hempel's deductive-statistical model of explanation. An example is given showing how human resource variables can be translated into rate concepts and then used in the context of the directive correlation and the deductive statistical model. The fourth frontier draws on complexity theory as a computational/analytical approach that directly incorporates idiosyncrasy by use of dynamical (nonlinear) methods. Complex adaptive systems, kinds of complexity, the causal role of complexity, and levels of adaptive tension likely to foster self-organization are discussed. An example shows how a complexity theory approach differs from a conventional explanation of why participative management decision making styles have failed to proliferate. The combined effect of rate dynamics, statistical mechanics, and dynamical analysis lays the platform for a realist, predictive, and generalizable quasi-natural organization science, thereby offering a possible resolution of the paradigm war. The mitigation of idiosyncrasy effects allows a reemphasis of background laws in …