Are there any philosophers that affirm the substantiality of consciousness without either falling into dualism or property dualism? I personally think that mind is a genuine reality but I'm not so certain that it is a substance in the sense that it is a reality with purely mental properties that exists separately from anything else. But I personally don't think property dualism is a viable alternative either.

Yes. The pioneering physicalists of the 1950s and 1960s, Smart, Armstrong and Place thought that. See I think it is misleading to think in terms of dualism versus monism. Even familiar properties of middle-sized and large ‘physical’ objects, such as size, shape, colour, rigidity, tensile strength, fragility and hardness are not identical to any properties at the level of quantum mechanics. ‘Physical’ is a loose lay term of little real use, and what we call ‘physical’ comes in many forms. In my view, mental properties are just more properties of middle-sized objects that are made out of wavicles, but do not reduce to quantum-level properties any more than , say, fragility does. I recommend pluralism about properties, rather than dualism or monism.

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