Fig. 1

Sequence and relationship of reasoning methods used in this article—focus on the dialogical principle. The three phases of scientific discovery given by Peirce are represented here (in the blue boxes). In the first phase, abduction (i), we argue for the need to conciliate both opposing kinds of ethics (1 & 2). For this purpose, we use the dialogical principle of complex thinking, which allows two antagonistic notions which are mutually exclusive and non-dissociable of the same reality to coexist: as with the Yin and the Yang, formally, one is part of the other, and symbolically gives it its significance (as the notion of rationality makes sense thanks to that of madness, and vice versa; Morin 1986). Dialogical etymologically means which concerns a speech between two. We thus obtain a formal and symbolic model (3). In the second phase, we detail in the article both kinds of deductions: descriptive (ii) then normative (iii), whereas the potentiality of the third phase (induction; iv) is evoked in the conclusion. All of these phases contribute to an iterative process that specifies the theory