 As mentioned in  Section 2,  dual-aspect approaches have a long history, essentially starting with Spinoza as a most outspoken protagonist. Major directions in the 20th century have been described and compared to some detail by Atmanspacher (2014). An important distinction between two basic classes of dual-aspect thinking is the way in which the psychophysically neutral domain is related to the mental and the physical. For Russell and the neo-Russellians the compositional arrangements of psychophysically neutral elements decide how they differ with respect to mental or physical properties. As a consequence, the mental and the physical are reducible to the neutral domain. Chalmers’ (1996, Chap. 8) ideas on “consciousness and information” fall into this class. Tononi’s theoretical framework of “integrated information theory” (see Oizumi et al. 2014, Tononi and Koch 2015) can be seen as a concrete implementation of a number of features of Chalmers’ proposal. No quantum structures are involved in this work.