This dissertation is devoted to dual-process theories, widely discussed in the recent literature in cognitive science. The author argues for a significantly modified version of the account suggested by Samuels (2009), replacing the distinction between ‘Systems’ with a distinction between ‘Types of processes,’ which allows a critique of both the (only) modularist accounts and the accounts describing a deep difference between two systems each having their specificities (functional, phenomenological and neurological). In the account of dual-process theories developed here, the distinction (...) between ‘Types of processes’ is considered, a priori, only as a heuristic distinction allowing to better understand the mind and to explain some of its properties. The main idea defended in this dissertation is that cognitive processes should be distinguished by their position in a multidimensional conceptual space allowing researchers to consider all of the characteristics and peculiarities attributed to a process, which is preferable to accounts forcing the process into either ‘System’ or either ‘Type’ identified in the most influential approaches (cf. Evans, 2008). Once this research program is in place, it will become possible to revise the concepts used and the categories defined to ground anew some of the notions we find in the literature (‘module,’ ‘System 1 / 2,’ etc.). The argument is made in three steps: -/- 1) The first chapter aims at a clarification of the notion of ‘module’ commonly used in cognitive science. Against the accounts aiming at a weakening of the notion in order to classify all of the mind’s processes as modular, the author – following most notably Faucher and Poirier (2009) and Samuels (2006) – casts doubt on how this notion is used by many influential authors, particularly in evolutionary psychology (e.g. Barrett, Carruthers, Cosmides, Tooby). -/- 2) The objective of the second chapter is to present, examine and criticize many dual-process theories and to suggest that no theory currently discussed is adequate to describe the architecture of mind. The accounts, especially influent or representative, suggested by Stanovich (1999; 2004; 2009), by Evans (2008; 2009), by Lieberman (2007; 2009) and by Carruthers (2006; 2009), are examined. -/- 3) In the third chapter, the author criticizes the framework developed by Samuels (2009) before developing his own account of dual-process theories and discussing some of its advantages. (shrink)