Lena: Miles, you mentioned that "steam whistle" idea—the notion that our consciousness is just a byproduct that doesn't actually do anything. But that feels so contrary to our daily experience. When I feel a deep sense of guilt, it can physically make my stomach knot up. When I feel love, my heart rate changes. How can an immaterial "feeling" have such a heavy physical footprint if it’s just a byproduct?
Miles: You’ve hit on the core of "interactionism." It’s the common-sense view that mental states and physical states are in a constant, two-way dialogue. Descartes was the first to really frame this as a problem for the West. He saw the mind as this "thinking thing" with no weight or size, and the body as a machine. But he couldn't ignore the fact that they do interact.
Lena: Right, but his solution—the pineal gland—was a bit of a "miracle" fix, wasn't it? He basically said, "It happens here," without explaining how something with no mass can push something with mass. It’s like trying to move a billiard ball by just thinking at it.
Miles: Exactly. That’s the "causal closure" problem. If the physical world is a closed system governed by the laws of physics—like the conservation of energy—then where does the "push" from the mind come from? If a thought causes a neuron to fire, that neuron needs a tiny burst of energy. If that energy doesn't come from another physical source, we’ve technically witnessed a miracle.
Lena: So, if we want to avoid calling every thought a "miracle," we have to look at other options. Some philosophers, like Malebranche, went the "occasionalism" route. They basically said that mind and body don't interact at all. Instead, every time you want to move your arm, God sees that "occasion" and moves your arm for you.
Miles: Talk about a high-maintenance universe! It’s a fascinating solution because it preserves the total separation of mind and body while explaining their apparent harmony. But then you have Leibniz and his "psychophysical parallelism." He used the famous analogy of two clocks. Imagine two clocks that are perfectly synchronized. They always show the same time, but they aren't connected by any gears. They just run in parallel because the "Clockmaker"—God—set them that way from the start.
Lena: It’s a beautiful image, but it feels so... deterministic. It suggests that my "soul" is just watching a movie of my "body" without any real agency. But what about "emergent dualism"? I was reading about William Hasker’s view. He suggests the soul isn't a separate thing dropped into the body, but it "emerges" from the brain’s complexity—like a magnetic field emerges from a magnet.
Miles: That’s a really helpful way to bridge the gap. A magnetic field is generated by the magnet, but it’s not the same thing as the magnet, and it can actually exert force back on other physical objects. In this view, the mind is a non-physical substance that is naturally generated by the brain once it reaches a certain level of organizational "threshold." It’s dependent on the brain for its existence, but once it’s there, it has its own unique properties.
Lena: And that would explain why brain damage affects the mind so profoundly. If the magnet is broken, the field is distorted or disappears. It respects the neuroscientific evidence without reducing the mind to just "meat."
Miles: Precisely. It also touches on what some call "property dualism." We only have one "stuff"—physical matter—but that matter has two very different types of properties. Physical properties, like mass and electrical charge, and mental properties, like "the feeling of sadness." These mental properties aren't just "hidden" physical properties; they are fundamentally different.
Lena: It’s like looking at a painting. You can describe it in terms of the chemical composition of the pigments—that’s the physical property. Or you can describe the "beauty" or the "emotion" it evokes—that’s the mental property. Both are "true" of the same object, but you can’t reduce the beauty to a chemical formula.
Miles: That’s a perfect analogy. And it brings us back to the "person." If we are just a collection of properties, where is the "I" that owns them? Some modern thinkers, like Daniel Dennett, argue that the "self" is just a useful fiction—a "center of narrative gravity." He says there’s no "captain" in the brain; it’s just a bunch of subsystems doing their own thing and reporting back.
Lena: But that feels so hollow, Miles! If the self is an illusion, then who is experiencing the "beauty" of that painting? The existentialists would argue that even if we are "thrown" into a biological body, we have a "transcendental consciousness" that allows us to step back and observe our own thoughts.
Miles: Right. And that’s the "vertiginous question" Benj Hellie talks about. Why am I me? Out of all the billions of subjects of experience in the world, why is this particular one—this body, these thoughts—the one that is "live" for me? Why am I behind these eyes and not yours?
Lena: That question actually gives me chills. It suggests that there’s a singularity to our existence that science can’t quite capture. It’s not just about "how" a brain works; it’s about "who" is living inside it.
Miles: And that "who" is what we call the person. In the Thomistic tradition, the person is an "individual substance of a rational nature." It’s not just a mind or a body; it’s a unified whole that has its own "act of being." This dignity isn't something we earn by being smart or functional; it’s something we are simply because of our nature.
Lena: Which is so important for how we treat each other. If dignity is based on "function"—like being rational or self-aware—then what happens to someone with advanced dementia? Or an infant? If they lose the "function," do they lose the "personhood"?
Miles: That’s exactly where the ontological view stands its ground. It says no—dignity is "inherent." It’s built into the "bricks" of our existence. Even if the "rationality" isn't currently active, the "rational nature" is still there. It’s the difference between a bird that is currently flying and a bird that has a broken wing. The bird with the broken wing is still a "flying-natured" being.