I was struck by Carey R. Carlson’s opening lines in the preface to his book, The Mind-Body Problem and Its Solution:
“The mind-body problem demands a description of how the mental and physical parts of the world go together to make up the whole. The problem was solved around 1927 by Bertrand Russell and Alfred North Whitehead.”
(1927 saw the publication of Russell’s Analysis of Matter, and was the year of Whitehead’s Gifford lectures which formed the basis of his Process and Reality.)
Since I think the Russellian stance on the mind-body problem is superior to the traditional options of dualism and materialism and also think Whitehead’s speculative process metaphysics was far ahead of its time, I was excited to see this passage and curious as to how well Carlson would back it up over the course of a short book. After reading the book I can say I think he did an excellent job in showing how the ideas from these thinkers can be put together into a compelling argument for a more coherent view of the world: that of a causal network of events which share a character which naturally underpins what we characterize as the mental and physical.
Carlson is an independent thinker and writer from Minneapolis who studied philosophy some years ago and concluded Russell and Whitehead had it right. He says he was perplexed that this seemed unappreciated. While he ended up pursuing a career outside philosophy, he finally was able to put together his views on the matter on paper (he put out this book in 2004). He and I corresponded via e-mail recently and that led to my interest in reading his work.
Both Russell and Whitehead explained why you cannot identify the world with our mathematical descriptions of it: you leave out the intrinsic qualitative character of the world we know via experience. Both philosophers showed, in somewhat different ways, that what we think of as mental events and physical events can both fit into a picture of a causal network, whereas our usual intuition of the world as a spatial container holding static objects or substance won’t work – whether one posits one kind of object or two.
Carlson’s outstanding contribution is to carefully describe what this ontology of causal relations can do: it can describe space-time and all that’s in it while also accommodating mental events. He then shows how scientific theory really is an elucidation of a causal web and how it must actually fit into our network of experiences in order to be formulated. This leads to the final postulate that all nature has a sentient character, and that this best explains how mind and world are unified. While I was already sold on this idea, I think Carlson’s book may convince other readers of the merits of a panexperientialist solution to the mind-body problem inspired by sound philosophy of science.
All in all, this book does credit to its ambitious title. Along the way, it is also a fine exposition of some of the work of two of our greatest twentieth century thinkers.
My chapter-by-chapter notes and comments follow below.
In the first chapter, he lays out the problem. Like others, he locates the “hard” problem for materialism in the raw feeling of being or sentience. He speaks of “the sensorium” of unified experience. If materialism or physicalism sees the mathematically characterized world as all that exists, then it does not include nor will it explain sentience – that which is given in phenomenal experience. The mind-body problem could be called the “phenomenology-physics problem”, he says (p.13).
Chapter 2 deepens this discussion, taking a closer look at the history of physics. Even with the advent of modern physics, taking quantum field theory for example, there seems to be a left-over tendency to conceive the world as physical matter or energy existing in a container of physical space. There certainly is no role for mental features in such a worldview.
After touching very briefly on some historical philosophical perspectives in Chapter 3, we start to move toward the solution in Chapter 4 with a review of Russell’s analysis of the world in terms of structure and relations (and specifically causal structure and relations). Here, Carlson pulls relevant passages from Russell’s Human Knowledge (this book I had not read – I had read the Analysis of Matter). Structure is defined as a pattern of relations. Relations relate terms of a class (which is just any definite set of entities). Russell discusses a variety of types of relations: dyadic and higher-order, symmetric/asymmetric, transitive/intransitive. Relata, relations and structure together form a complex, which is a whole or a fact. This approach can be seen as applying to pure mathematics, and it can also be seen as characterizing the phenomena of the world, as presented to us. In physics, we apply mathematics to real world phenomena. But one can’t identify the phenomena as identical with the mathematical description. Here’s a quote from Russell: “There is, however, a very definite limit to the process of turning physics into logic and mathematics; it is set by the fact that physics is an empirical science, depending for its credibility upon relations to our perceptive experiences.”
While Russell’s philosophy of science is obviously not unknown, commentators I have read don’t always stress the role of relations in his analysis. The fact that the world is made of relations (rather than the static objects or “stuff” of our intuitions) is a key point for Carlson, which will also provide the link to the work of Whitehead (Carlson notes with interest the history here: while Russell and Whitehead were famous for their collaboration on the Principia Mathematica, that seemed to be the end of their formal work together – yet the “fingerprints” of this shared history writing the Principia can be seen in their similar later critiques of the role of logic and mathematics in science).
In Chapter 5, Carlson argues that the most basic feature of physics, space-time, can be analyzed in terms of causal structure. Here he gives credit to the role the theory of special relativity played in showing the way forward: in it we can see how causal relations could be responsible for both spatial and temporal order. Since causal relations are relations in time, it is the temporal ordering of events which is fundamental, while the spatial is derived.
Since “real” causation is an asymmetric relation, Carlson shows how we can use arrows to graphically illustrate causal relations. One can see how “space-like” and “time-like” relations between events arise from a causal structure. He then shows how a “particle” could be defined as a recurring pattern of activity -- a certain geometric pattern repeated along a time-like route in a larger causal lattice). One of Carlson’s interesting ideas is that since different numbers of arrows could connect two given events, one gets a notion of relative temporal frequency. This allows for the introduction of the concept of energy into a causal network of events.
With these examples, we can see how the notion of the physical world (traditionally seen as a spatial container plus stuff inside it) can be replaced by a network of time-like causal relations alone. This is consistent with a basic notion of what science does: it looks at the world and analyzes what comes before what. Carlson notes that progress in physics eventually arrived at quantum events – discrete events which “do not admit of further before-and-after analysis” (p.71). These elementary events and the causal connections among them constitute the world. So the physical world is not space plus what it contains, but rather time-like causal relations only. And this picture is one which allows for the solution to the mind-body problem.
In Chapter 6, Carlson argues that mental events can be located in the causal network in the same way as “physical” events. Our experience can be seen as participation in a sequence of time-ordered mental events. So, do mental and physical events “interact”? Interactionist dualism is often seen as an incoherent perspective on the mind-body problem. But we’re not talking about static substances. Russell reminds us that mental events are unavoidably part of the causal network which describes the world, since the structure of physics has to empirically connect to the sensations of the physicist. Mental and physical events are interspersed in the causal network. Now, our human experiences seem very different than the entities of micro-physics, but when you break down it all down, both can be situated in a causal network. “The distinction between mental and physical now hinges upon the assumption that mental events are characterized by sensory qualities, while physical events are not. (p.87)”
Carlson does a good job in this chapter in trying to break down our intuitions, and it’s hard to do it justice in this summary. But I think he does a good job showing how an event ontology can situate the mental as well as the physical in one world-web. Some questions arise here: what are the base-level indivisible quantum events connected by the arrows of causal relations, such that they can form the basis for everything? What is the quantum event’s intrinsic nature?
Heading toward an answer to this is the discussion in Chapter 7. While in Chapter 6 Carlson tries to show how mental events can be situated in a world we think of as physical, in Chapter 7 he (again leveraging Russell) shows that we really do need to invert this. All physical theorizing and experimentation does take place within the context of mental events. This shows there really is no reason to distinguish between the two kinds of events. Science gives us nothing but causal structure. We know some causal events have a mental character and the physical events are only known via the mental.
Russell “stops” at this point. He was agnostic about whether the intrinsic character of the physical (non-directly experienced) events was also of mental or sentient character in any way. He said we just don’t know. Phenomenal character is the only kind of intrinsic quality we’re familiar with, but we can’t know the intrinsic character of the rest. Given this stance, some have cast Russell’s theory as a form of neutral monism.
But Carlson wants to go further, so he states that his final chapter (no.8) “belongs to Whitehead”. Whitehead’s critique of materialism was very similar to Russell’s (for example the first several chapters in his Science and the Modern World). But in Process and Reality, he was much more ambitious. Among other things in that work, he goes ahead and postulates that all events have a sentient character. Carlson endorses the idea that it is both fitting and simpler to posit this, rather than to assume there is some other unknown form of intrinsic content. Further, under this assumption, the world just makes more sense in terms of unifying the human experience with the rest of the world. In Whitehead’s theory, the causal structure of all events are grounded and ordered in the same way.
Carlson does a good job in just a few pages in summarizing some of Whitehead’s ideas. This is difficult because of all of Whitehead’s invented terminology and his hard-to-penetrate prose “style”. Whitehead’s treatment of causation is richer than what Carlson has discussed so far, including the transition from subjective to objective poles for each event, and the inclusion of purpose and self-determination as a causal factor in the setting the course of events. He also discusses Whitehead’s treatment of the unactualized possibilities (eternal objects) which are presupposed by the view that the temporal process establishes the contingent facts of the world. He finally then discusses Whitehead’s theory of how events (occasions) are organized into enduring societies and how the parts work to satisfy the determination of the whole -- a template for describing the human mind.
I don’t have very much critical to say about the book except as it relates to my thinking about what might be added to expand the discussion. Events and causation are the primitives in the theory. Until the final chapter on Whitehead, how causation works is not described. We can probably improve on Whitehead in this area (Gregg Rosenberg’s theory would be one to possibly consider). Related to this would be drawing more connections to an interpretation of quantum mechanics to better describe what is going on in an elementary quantum event and what the status is of wavefunction associated with a quantum system. Also, we need to someday improve on Whitehead with regard to the combination or composition problem – explaining how micro-events clump up into macro-events like the ones making up human experience.