Panpsychism is the idea that basic physical entities are essentially micro-consciousnesses and that our macro-consciousnesses result from combining the phenomenal natures of the physical entities that constitute us. The view faces the combination problem: how do simple, discrete micro-consciousnesses combine to produce complex, unified macro-consciousnesses? This problem has been much discussed, but there’s an aspect of it that has, I think, been relatively neglected. Here it is.
It looks like a sensible methodological assumption that if two entities are qualitatively identical from a physical point of view, then they are phenomenally identical too. If panpsychists don’t make this assumption, then it’s hard to see how they could construct anything like a science of consciousness. If panpsychism is true, then we are acquainted with only a tiny fraction of phenomenal reality — the portions that constitute our consciousnesses. The rest can be known only indirectly, by inference from corresponding physical features. But if phenomenal properties could vary independently of physical ones, then there would be no stable phenomenal-physical correspondences, and the bulk of phenomenal reality would not be even indirectly accessible to us. This could be case, but if it is, then there is no hope of explaining consciousness.
If the assumption is true, however, then it follows that there is very little phenomenal variation at the fundamental level. There are only a few types of fundamental particles, and all tokens of these types are qualitatively identical from a physical point of view, differentiated only by their spatio-temporal location. Every up-quark is physically identical to every other up-quark. So all tokens of each particle type are phenomenally identical too. (Differences in their spatio-temporal location are relational ones and cannot affect their intrinsic natures.)
It follows that fundamental phenomenal reality is quite uniform. There will just be a few different phenomenal ‘notes’ played billions upon billions of times. The combination problem is thus doubly difficult: the phenomenal elements from which our macro-consciousnesses are formed are not only simple but few in number, and we must explain how variety emerges from uniformity as well as how richness emerges from simplicity.
But this isn’t all. There is another aspect to the problem, which looks even more challenging. It’s a dynamical aspect. For if our assumption is sound, the phenomenal properties of the fundamental entities never alter. Fundamental particles do not change or age. So, except in exotic circumstances where particles are created or destroyed, the overall phenomenal soundscape stays the same, unaffected by particles’ changes in location (which, again, are irrelevant to their intrinsic natures). The fundamental phenomenal world is almost completely static. How, then, does a dynamical, ever-changing human consciousness emerge from a static phenomenal base? We might call this the dynamical combination problem.
Of course, all this assumes a rather old-fashioned picture of the microphysical world as one of discrete fundamental particles located in spacetime. The problem may look different, and perhaps more tractable, if we adopt a more sophisticated physics.
If you have any thoughts on this problem or any references to relevant discussions in the panpsychist literature, do please post them in the comments.