Minimal physicalism as a scale-free substrate for cognition and consciousness

Context switches are hard to measure, as doing so requires predicting what “background” variables are relevant in fact to how an event is processed, a prediction problem that is in general intractable (Dietrich and Fields 2020). Saltatory changes in event representations, e.g. canonical “Aha!” moments (Kounios and Beeman 2015), may reflect context-driven QRF changes. Basal systems may provide uniquely manipulable windows into such processes: e.g. Pezzulo et al. (2020) have recently suggested that bioelectrically driven saltatory morphological changes in planaria may employ the same underlying mechanism as saltatory changes in episodic memories in mammals.

Quantum theory has had a long and somewhat disreputable association, dating back at least to von Neumann (1932), with the science of consciousness. A dominant concern, beginning at least with Wigner (1961) and extending through Penrose (1989), Schwartz et al. (2005), and Hameroff and Penrose (2014) to Georgiev (2020) has been to employ quantum theory to establish an ontological foundation for a science of consciousness. Our interest here has not been ontological, but rather empirical: to derive as much as possible from the simple assumption that consciousness involves information exchange subject to the constraints of quantum information theory. We have shown that the MP framework that follows from this assumption allows many of the key features of consciousness to be understood as simple, scale-independent consequences of thermodynamics.

In direct contrast with strict Cartesianism, MP holds that we can better understand our own awareness by understanding the awareness of our more basal cousins. Our homeostatic/allostatic drives and the mechanisms that satisfy them are phylogenetically continuous with those of prokaryotic unicells including E. coli. Our concepts and categories are implemented by QRFs playing the same roles, and satisfying the same basic requirements, as the Che-Y system regulating bacterial chemotaxis. The tradeoffs that we implement, and adjust in real time, between perception, memory, and planning are tradeoffs that have been explored and adjusted in niche-specific ways by all organisms throughout evolutionary history. We can take advantage of these fundamental mechanistic similarities to design theoretical and experimental paradigms that reveal and assess scale-free properties of consciousness in both natural and engineered systems.

The authors thank E. Dietrich, D. Hoffman, A Marcianò, C. Prakash, and R. Prentner for relevant discussions, noting that they may nonetheless reject some or all of our conclusions. They also thank the two reviewers for their careful reading and helpful comments.

M.L. gratefully acknowledges support of the Barton Family Foundation, the Elisabeth Giauque Trust, and the Templeton World Charity Foundation.