Towards a Physical Theory of Subjective Mental States

Abstract

Any complete theory of physical reality must allow for the ubiquitous phenomenon of subjective experience at some level, or risk being conceptually incoherent. However, as long as the ontological status of subjectivity itself remains unresolved, the topic will be seen as more within the purview of philosophy than of physics. Towards a resolution of this issue within empirically motivated physical theory, this article introduces an operational definition that ultilizes the general consensus that subjective mental states, whatever else is controversial about them, at least correlate in some way to physical states. It is shown here that implementing this underappreciated assumption within the framework of a physical theory in fact leads to wide-ranging consequences. In particular, a correlation requires there exist a well-defined mapping from a space of subjective mental states onto a space of information-bearing elements of some physical theory. Given the peculiar nature of subjective states as inherently private appearances, any empirical identification of states must be performed by the experiencing subject. It is argued that such an operationally defined 'self-measuring' act leads unavoidably to an 'uncertainty principle' that is analogous in some intriguing ways to Heisenberg's principle for quantum mechanics. A model is then introduced for subjective states as algorithmically incomputable numbers. Additionaally, an inequality similar to Bell's theorem may be derived, indicating an analogy with the violations of local reality and the ontology of observables within quantum mechanics.