Why did Chalmers shift from idealism to dualism? And Russell from materialism to neutral monism?
Edit: The particulars of Russell is recounted in A.C. Grayling's 'Russell: A Very Short Introduction' (1996/2002). I reread the section and gather Russell was dealing with how entities are related to percepts by means of interfaces or interfacing through separate laws expressing physical conditions or mental ones.
I can't exactly locate where Chalmers made the shift, but he now consistently emphasises that matter and mind may both be fundamental properties of nature in his interviews and moved from the propostion of things possibly having experiences (his famous thermostat example) to things possessing experiences about them.
I'd like to know the motivation and import behind the shifts coming from either direction, that of materialism and of idealism. Are these converse positions trying to resolve a general problem about the constitution of reality and how can that central problem be described?