Clearly, I’m a fan of this book. This is no doubt partly because I was already persuaded by the panexperientialist approach to solving the mind/body problem (and I have believed Quantum Mechanics provided evidence for panexperientialism as well). But Rosenberg has added important new strength and depth to panexperientialist ideas by addressing the metaphysical problems posed by causality and showing their connection to the existence of subjective experience in the world. In particular, his system puts forth a credible way to solve the combination problem in showing how experience might participate in causal structures across all levels of nature, including our own “middle” macroscopic level.
In terms of criticism, I was first put off by the fairly complicated nature of the causal model which provided the bulk of the second half of the book. At the level of specificity Rosenberg has given, he has pretty much guaranteed that many details will prove to be wrong in describing our world. There was a part of me that thought the conceptual arguments may have been stronger with less detail (sometimes “less is more”). On the other hand, after getting through it, I thought that the effort could still pay off by showing an example of what to look for as we investigate nature.
To be more specific, it is scientists who need to explicate the receptive/experiential side of nature and find out how it really works. They won’t find anything, of course, until they know what to look for. It is my hope that the irreducible presence of subjective points of view in nature will eventually be taken seriously enough to guide science in new directions. And while it is the case that the “hiddenness” of first-person experience to third-person investigation is an obstacle to investigating this part of the natural world, if Rosenberg is right about the impact the experiential pole has on causality, then it does leave its tracks on nature. Certainly, the interpretation of QM is one area which can be rethought, and the construction of new cosmological theories which include QM will likely be influenced. But I speculate that the other great place to look for evidence of this other aspect of causality is in the area of complex systems. Non-linear dynamical systems display organizational features which are resistant to reduction to micro-physical causation. A new approach may pay dividends here.
My main question about Rosenberg’s approach relates to the concept of time. When giving his examples and diagrams explaining how the effective and receptive properties fit together to form natural individuals in chapters 9 and 10, he pictures this taking place against a fixed background of space and time. Implicitly, space and time are more fundamental entities. Then, in section 10.6, he adds a discussion of how space and time could be seen as emerging from an underlying more fundamental causal mesh.
Here, he says an ingression of an individual from possible to actual is an atemporal process. Then a series of asymmetric connections (he names this a “cascade”) among actualized entities could give rise to time. Then, another step shows how distance in space could be viewed in terms of another set of connections. To make this work, Rosenberg also has to add the ideas of non-local “signals” which propagate between cascades to keep things in sync.
Finally, in section 14.3.2, the attempt is made to link the discussion in 10.6 to the subjective flow of time experienced in human consciousness. Here, he admits the flow of time is not easy to reconcile with the “objective yet panexperientialist” model of nature. So there is a distinction between time in the fundamental picture – Rosenberg decides to call it inter-subjective time (which is derived ultimately from the causal mesh as in section 10.6) -- and subjective time. He then warms up to the existence of subjective time and proposes that this subjective flow “carries” the asymmetry of the causal process which gave rise to time in the first place.
While I admire the effort here, I found this two-fold nature of time somewhat unsatisfying. Rosenberg shows that experience and causality cannot exist without each other, but I would speculate that time itself is part of this relationship in an even more intimate way. There really isn’t any causality or experience except in subjective time - subjective time is the dimension of existence which co-arises with the causal process. There is no “objective” time, and this is OK – we shouldn’t expect any and the notion of true objectivity is an impossibility anyway. Now unlike Rosenberg, I’ve just presented a few bald statements and haven’t worked out anything like a complete competing picture of how this works, so for now I’ll just assert it is a topic worth further thought.
To conclude, I thought this was an excellent and thought-provoking book which really moves the discussion forward toward an improved metaphysics of the natural world. I hope the ideas in it gain circulation.