This is the end of chapter 7 of my dissertation (which, God willing, I will eventually finish turning into a book). It explains my impolite, honest assessment of physicalism in philosophy of mind.
When discussing the content of the first chapter of this work with others, one common response is a sort of ad hominem along these lines: “you say we should be suspicious of interesting views, but interactive substance dualism is an interesting view, so shouldn’t be we suspicious of it?” My answer to this question is that dualism isn’t really interesting. Although the view is interesting in philosophical contexts given that it is widely rejected in the field, it isn’t interesting in the more general sense of going beyond or countervailing our experience of the world. Interactive substance dualism is the combination of the trivial facts that (1) introspectively accessible mental states aren’t physical, that (2) they are causally relevant to behavior, and that (3) they are aspects of a substance whose modal nature is distinct from the modal nature of our physical bodies. These views are either simple consequences of introspection or else consist in basic modal intuitions. Their combination therefore doesn’t rise to the level of a theoretical hypothesis. Instead, it is just the consequence of direct observation and conjunction. It is an odd feature of philosophy that the same views are often attacked as both highly simplistic and naïve and as overtly mysterious and incomprehensible. Dualism is often thought to be both a persistent aspect of common sense and a bizarre and incomprehensible view that posits strange substances and incomprehensible forms of causation. I will address the concerns over the mysteriousness of dualism in the subsequent chapters. For now, I would like to explain quite simply why I find dualism uninteresting.
In presenting the case for the view that dualism is part of common sense and that physicalism is fundamentally at odds with common sense ontology, I have tried to be as fair to the physicalist as possible. I tried to explain in a detailed way exactly what features of the mind draw one to think of it as an immaterial substance, and how these aspects of the mind fit together into a cohesive whole. I have tried to show how this conception fits into a sense of people as rational and moral agents, and how this shows that a materialist view of human nature is at odds with basic assumptions about human nature we carry with us in life. I have done this because it is necessary. Physicalism dominates contemporary philosophy of mind, and contemporary intellectual life in general. I have tried to treat with it with as much respect as possible. But for a moment, I would like to step away from this attitude of respect and explain why I think this should not have been necessary. If nothing else, this effort should help physicalists see just why it is that so many people have such a hard time accepting their view. Here is how the debate seems at least to this dualist, and likely to many others. Although physicalism requires respect because of its broad acceptance among those I am engaged with in debate, but the view itself has never actually deserved it. Here, briefly, is why:
In introspection, we are aware of many of our mental states. We can look within ourselves and see what is going on. In our experiences, we are often aware of what is happening inside of us in addition to what is happening outside of our minds. In addition to what the experience is of, there is a way it feels or a “what-it’s-like”-ness that is a distinct feature of the experience. When we focus on these features of our lives, we are aware of intrinsic aspects of their nature. Think, for a minute, about a experience of joy. In such an experience, there is a certain acuteness, a level of intensity, and a distinctive phenomenology or flavor to it that is a recognizable part of the sensation. This is, indeed, the aspect of joy that most draws our attention and that we are most readily familiar with in experience. Of course, there are also physical events occurring at the same time. Often, there is activity in or uplifting of your chest and your heart rate and breathing likely change to some degree. Muscles move in your face and your posture often changes as well. But these physical events are incidental. What makes joy what it is lies the aspects of the sensation itself. Focus for a moment on a particular instance of that sensation. Focus in particular on those features of it such as its intensity and its experiential flavor. According to physicalists, those features aren’t anything more than various physical processes transpiring in your body at that particular moment. Unless one is a behaviorist, it won’t be the list above, but according to all physicalists, that experience and those features of it ultimately consist in nothing more than matter arranged in a complex way. Physicalists say this despite the fact that the experience of having the sensation appears to be a complete and distinct thing in its own right, separate from any physical goings-on. They say it despite the fact that the experience appears to have its own features, and a nature that is quite different from the nature of any of those physical events. They say it despite the fact that it does not appear to be made up of little bits of stuff, and despite the fact that it appears not to have any mass or to be the sort of thing you could put in a test tube or cut up into parts or push along thin fibers of tissue in the form of synaptic firings. Somehow, despite the massive apparent difference in nature between these particular instances of the experience of joy and the particular physical events occurring in your body, the one thing is supposed to be nothing more than the other. That is what physicalists are asking us to believe. And that is simply crazy. Two things that are so very unalike and so obviously different on their face simply cannot be one and the same. We could accept many different theories on the underlying physiology of, say, dogs. But we could and should never grant the hypothesis that their true nature shows they can’t have fur, never bark, have no legs, breathe through gills, and live their lives swimming in the sea. Such a theory simply cannot be true.
And why is it that they are asking us to believe that their theory is true? Well, primarily because when we have the experience of joy we see certain physical events happening in the body. They appear to co-occur, and the physical stuff seems causally related both to the physical events that brought about the emotion and to the physical events, such as your subsequent behavior, that follow the experience. And isn’t it much neater is we just say there’s one thing there instead of two? Well, my dad delivered mail for more than two decades. When he would go out to deliver mail, he would drive around in a mail truck on his routes. Wherever he went to deliver mail, the truck was right there with him. We know that part of what makes someone a postal carrier is that he meets the description of “going around town and distributing mail to various locations.” But there is something else that also fits this pattern: the truck. But one would have to have a seriously diminished understanding of what a postal carrier is, and would also have to think that only metal detectors or views from the sky were legitimate ways to detect a postal carrier, to look at the pattern and say that mailmen are actually large, heavy, metal objects with four wheels and internal combustion engines. This could be a revolutionary new account of the nature of mailmen if one were to simply ignore all the evidence that let us know they are human beings and to only accept evidence that could detect trucks. But I knew my dad, and I’m quite certain that he was not a truck. I recognize his features and the ones he lacks, and I know that, although a particular truck was there when he delivered mail around town, at no point was my dad made of metal, have four wheels, or have an internal combustion engine. The fact that he happened to overlap in some of his interactions with the world with such an object doesn’t make them the same, and doesn’t even make it possible that they could have been the same. And when I introspect, I am also aware of things, such as particular sensations of pain. I am aware of various features they have, like their intensity and acuteness, an intrinsic negative quality, and a certain ineffable “what it’s likeness” that goes beyond these features. I am also aware that they aren’t composed of matter, don’t have any mass, and don’t move quickly through a bunch of squishy grey stuff. You can tell me all you want about how certain physical events are present when the pain is there, and how those events seem to be relevant to my behaviors such as saying “ouch” or getting a band-aid, but I’ve introspectively seen my sensation of pain just like I’ve visually seen my dad, and I know first hand that what I’ve seen in introspection is not that thing you see accompanying its causal role in your laboratory. Point to any instance of brain activity and try to say it is acuteness or intensity, that it is intrinsic badness or has a feature of being like something, that it is an experience had by a subject and felt with anguish and a longing to fix or remove it, and I will look at you like you have three heads. These things are simply different. Asking me to believe otherwise would be like asking me to believe that my dad was actually a large, heavy truck.
Physicalism is so manifestly contrary to our experience of ourselves that it would take a massive and widespread intellectual bias against all forms of introspection and against the legitimacy of common sense in general to have ever gotten to a point where it was even taken seriously, let alone widely accepted. When engaged in a defense of a view like this, people often find a way to move past this point of initial resistance and to think that they are doing serious work trying to figure out a great mystery. Brilliant minds spent centuries, for example, engaged in the opposite task of developing complex and fascinating theories about how things like your brain and the rest of the physical would could actually be nothing more that mental features of reality, and the array of idealisms that came out of this effort were astounding in scope and in creativity. But none of them ever had a chance of being true. And none of them ever should have been taken seriously as legitimate ways of conceiving of reality or of human nature. The same is true of physicalism. Brilliant minds have justified to themselves ways of looking past the obvious falseness of their view, and are currently engaged in amazingly complex and brilliant attempts to defend something that can’t possibly be correct. At least, I think this is how the debate is seen by many dualists, and is a large part of why the debate appears so intractable. If this is correct, then the effort is also a tragic waste of rare genius.