Purpose - The purpose of this paper is to lay down the methodological structure of the epistemology of tawhid (Oneness of Allah). In this paper, the meaning of tawhid also refers to the monotheistic unity of knowledge (consilience) in the cast of its organic pairing by circular causation relations between the moral and material possibilities. The paper thereby raises the critique of mainstream economic reasoning and its imitation by existing Islamic economics. Consequently, by the ontological, epistemological and phenomenological foundation of tawhidi methodological worldview, an altogether new socio-scientific reasoning in generality and economic reasoning in particular is introduced. Design/methodology/approach - The socio-scientific meth...