Here’s how not to be misled by the magical phrase “emergent properties,” in discussion of what constitutes all of reality.
First, remember the question at hand, when discussion of emergent properties comes up. The question is: what constitutes all of reality? Does it include only what we describe as “nature?” Or does it also include a deeper reality transcending nature—supernature? Is the “naturalist” view of reality correct? Or is there also a God, or gods, or some sort of sentient Presence animating nature?
If we start with a naturalist presumption (big “if”), then we can subscribe to the notion that all of what we know to exist consists of matter in motion. That matter exists in the form of fundamental particles: atoms (or even more fundamentally, quarks and leptons). There are a finite number of types of atoms. They’re found in the periodic table—the elements. These kinds of atoms combine in innumerable combinations, called molecules.
In its most reduced form, we can say that all of the stuff around us is composed of these molecules. Molecules and the particles within them are in motion, all the time, as a result of fundamental forces of nature: gravity, electromagnetism, strong and weak nuclear forces. If you’re sitting on a chair, that chair seems solid, but if you were to greatly magnify a tiny piece of it, you would see these fundamental particles moving through space, in response to attracting and repelling forces.
We are only talking so far of nature—of physical reality. But we are talking about all of nature. It is all comprised of these fundamental particles and forces. These fundamental particles and forces are the study of physics and chemistry. But all of the sciences, and indeed all of our endeavors within the physical realm, are reducible to these fundamentals. That is, everything within nature can be described in terms of fundamental particles and forces; matter in motion.
When we think of a chair, we don’t normally think of it in terms of these particles in motion. We would say that the chair has properties apart from those fundamentals. The designer of the chair and the artisan who worked materials into the form of a chair couldn’t care less about the fundamental particles of which the chair is comprised, or the forces acting on those particles. So if the particles and forces are the fundamental component of the chair with which the designer and artisan are concerned, why do they not think in terms of atoms and molecules and forces acting upon them?
Obviously, they’re concerned with properties of the materials on another scale altogether: hardness, pliability, aesthetics, strength, and so on. It is true that those properties exist because of the underlying fundamental properties of particles and forces, but they can be (and as a practical matter, must be) considered without reference to those fundamental properties. The artisan needn’t understand particle physics to build a chair. The physicist might be a lousy chair-maker.
So the properties that the artisan is concerned with are qualitatively different than those with which the particle physicist is concerned. The hardness, pliability, and so on of the materials are properties which are said to “emerge” from the fundamental particles and forces. One might go further and say that properties of the completed chair, like comfort and height and purpose, are further emergent from the fundamentals of physical things. The properties of the chair, and the properties of the chair’s materials, are describable as “emergent” because they emerge from the fundamental facts of the chair’s existence within physical reality.
All we’ve really done so far is describe the same thing in different ways; from different perspectives; for different purposes. The particle physicist has one way of thinking of the chair; the artisan who built it another. Both would describe the chair’s properties, but they are talking about completely different and non-overlapping sets of properties.
The reason to be conscious of this idea of emergent properties is because, although it is true as far as it goes, it is sometimes used to obfuscate our understanding of the whole of reality. The idea is used in service to a false syllogism, like this: (a) all of physical reality is reducible to fundamental particles and forces; and (b) non-physical properties emerge from those physical fundamentals; therefore (c) all seemingly non-physical properties are really only emergent properties.
See the flaw? It’s circular. If a chair is “beautiful,” we can say that its appearance emerges from fundamental physical properties of atoms and forces, but that does not fully explain beauty, of chairs or anything else. It does not and cannot explain a host of non-physical properties, like practicality and usefulness and purpose. Truth and honor and virtue are non-physical properties, too, but it is quite a strain to make those properties out to be merely emergent of physical properties of humans. Though some non-physical properties are emergent, it does not follow that all non-physical properties are.
The idea of emergent properties is employed to say that because there are fundamental elements of matter and motion, all of reality is reducible to those fundamental elements. This is a non-sequitur. Physical things may be reduced to those fundamentals, but that doesn’t mean that physical things are all there is.
We considered chairs. Now consider human beings. Like a chair, a human body is composed of fundamental particles in motion. People are living things, however, unlike the chair. So is life itself merely an emergent property of matter? That is the naturalist position, and the one that is dominant in our culture now. But again, it doesn’t follow, at least not solely from the fact that some properties are reducible to fundamental particles and forces.
How about human consciousness? Surely that is a distinguishing property of humans, as compared to chairs and rocks and water and perhaps even other animals. Here are some properties of consciousness: inner subjectivity of experience, self-awareness, other-awareness interacting with self-awareness, intentionality rather than mere passive reaction, volition, memory, continuity, and others. Are these all emergent properties of the atoms and forces at work within the body? That is the naturalist position; again, the one dominant in our culture now.
One might be a dedicated atheist materialist, but hopefully not because of misapprehending the significance of emergent properties of matter.