The main purpose of this article is to identify the inner human activity Peirce calls musement with the mental processes that arise through the workings of the brain’s default mode network. This network is a specific, recently anatomically defined brain system, which is most active when individuals are not focused on the external environment. In doing so, musement, which was defined by Peirce over a hundred years ago, will finally be situated within what today we understand as its neurobiological origin.

Following the Peirce’s proposal drawn in the Neglected Argument, here we focus on the equivalence, from the generative and methodological point of view, of what we will call the religious and scientific abductive experiences. To articulate these connections, we also rely on William James's Gifford Lectures collected under the title The Varieties of Religious Experience. Moreover, we study extensively the universality of the Musement which is related to the mental processes that lead to the generation of the most creative abductions; (...) finally, we fully identify the Musement with a recent discovery of neuroscience, the brain’s default mode network. (shrink)