The Big Picture
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some crucial nonphysical component to a human being, everyone admits
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that the particles are part of who we are. If you want to say there is some-
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thing else, you have to explain how that something else interacts with the
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particles. How, in other words, the Core Theory is incomplete, and has to
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change.
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To address this issue seriously, we wouldn’t necessarily need to have a
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“Soul Theory” that is as rigorous and well developed as the Core Theory of
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physics. We would, however, need to be specific and quantitative about how
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the Core Theory could possibly be changed. There needs to be a way that
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“soul stuff” interacts with the fields of which we are made— with electrons,
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or photons, or something. Do those interactions satisfy conservation of en-
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ergy, momentum, and electric charge? Does matter interact back on the
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soul, or is the principle of action and reaction violated? Is there “virtual soul
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stuff” as well as “real soul stuff,” and do quantum fluctuations of soul stuff
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affect the measurable properties of ordinary particles? Or does the soul
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stuff not interact directly with particles, and merely affect the quantum
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probabilities associated with measurement outcomes? Is the soul a kind of
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“hidden variable” playing an important role in quantum ontology?
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If you want to be a dualist and believe in an immaterial soul that plays
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any role whatsoever in who we are as human beings, these questions are not
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optional. We’re not rigging the game by demanding a full- blown mathe-
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matical theory of the soul itself; we’re simply asking how the soul is sup-
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posed to affect the mathematical theory of the quantum fields that we
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already have.
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Put aside for the moment the possibility of an immaterial soul, or other
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nonphysical effects that could influence our lives here on Earth. Let’s con-
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sider the most straightforward construal of our present state of knowledge:
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the Core Theory underlies everything we witness in our everyday lives, in-
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cluding ourselves. What are the consequences of that picture for our hu-
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man capacities, as well as for how we think about our place in the cosmos?
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We’ve already alluded to the most obvious repercussion of the Core
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Theory: you can’t bend spoons with your mind. Actually you can, but only
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by the traditional method: sending signals from your brain, down your
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arms, to your hands, which then pick up the spoon and bend it.
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The argument is simple. Your body, including your brain, is made up of
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only a few particles (electrons, up quarks, and down quarks), interacting
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through a few forces (gravity, electromagnetism, and the strong and weak
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nuclear forces). If you’re not going to reach out and touch the spoon with
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your hands, any influence you have on it is going to have to come through
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one of the four forces. It won’t be through one of the nuclear forces, since
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those reach only over microscopically small distances. And it won’t be
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through gravity, since gravity is far too weak. (If you didn’t know about the
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Core Theory, you might think you could imagine simply increasing the
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strength of gravity, or otherwise manipulating it. In the real world, that
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won’t work. A collection of particles, such as your brain, creates a very pre-
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dictable gravitational field, determined by its total energy. We don’t live in
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a science- fiction movie.)
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We’re left with electromagnetism. Unlike gravity, the potential electro-
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magnetic force from your body actually is strong enough to bend spoons—
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indeed, that’s what happens when you use your hands. All of chemistry is
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essentially due to electromagnetic forces acting on electrons and ions (at-
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oms that are charged by having more or fewer electrons than protons). To
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greatly simplify a complex biological process, muscle contraction occurs
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when calcium ions provoke one kind of protein (myosin) into pulling on
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another kind of protein (actin), using energy stored in adenosine triphos-
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phate (ATP) molecules. It’s an interplay between a relatively modest collec-
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tion of electrons, ions, and electromagnetic fields, but it’s enough to provide
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the necessary oomph to bend a spoon as you will.
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We might imagine that a brain could be able to somehow focus electro-
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magnetic energy in such a way as to create forces on distant objects without
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actually touching them. While the brain is chock- full of charged particles,
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for the most part the electric field associated with them cancels out because
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there are an equal number of positively charged protons and negatively
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charged electrons. Conceivably, those particles could move about and ar-
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range themselves in the right way to create an electric or magnetic field that
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could bend a spoon. (Charged particles at rest are surrounded by electric
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fields, while charged particles in motion generate magnetic fields in addi-
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tion.) Something like that, after all, happens with radio transmitters and
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receivers: signals are sent when charged particles in motion create electro-
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magnetic waves, which then start charges moving inside the receivers.
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Having the brain function as a kind of electromagnetic tractor beam
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would not violate the laws of physics, but it doesn’t work for more mundane
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reasons. The brain itself is subtle and complicated, so we could imagine
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generating a large electromagnetic field. But once generated, that field
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would be a blunt instrument. Spoons are not subtle and complicated; they
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are just inert pieces of metal. Not only would any brain- produced
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electromagnetic field have no special reason to home in on a spoon in the
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desired way; it would be incredibly easy to notice for other reasons. Every
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metallic object in the vicinity would go flying around in response to this
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force field, and it would be straightforward to measure it using conven-
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tional methods. Needless to say, no such field has ever been detected, while
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quite a few illusions that give the impression of magical spoon bending have
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been unmasked.
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The same goes for phenomena such as astrology. The only fields that
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could possibly reach from another planet to Earth are gravity and electro-
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magnetism. Gravity, again, is simply too weak to have any effect; the gravi-
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tational force caused by Mars on objects on Earth is comparable to that of
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a single person standing nearby. For electromagnetism the situation is even
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clearer; any electromagnetic signals from other planets are swamped by
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more mundane sources.
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There’s nothing wrong with doing elaborate double- blind studies to
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look for parapsychological or astrological effects, but the fact that such ef-
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fects are incompatible with the known laws of physics means that you
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would be testing hypotheses that are so extremely unlikely as to render it
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hardly worth the effort.
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There is a much more profound implication of accepting the Core Theory
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as underlying the world of our everyday experience. Namely: there is no life
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after death. We each have a finite time as living creatures, and when it’s over,
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it’s over.
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The reasoning behind such a sweeping claim is even more straightfor-
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ward than the argument against telekinesis or astrology. If the particles and
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forces of the Core Theory are what constitute each living being, without
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any immaterial soul, then the information that makes up “you” is contained
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in the arrangement of atoms that makes up your body, including your
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brain. There is no place for that information to go, or any way for it to be
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preserved, outside your body. There are no particles or fields that could store
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it and take it away.
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This perspective can seem strange, because on the surface there appears
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to be some kind of “energy” or “force” associated with being alive. It cer-
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present. Where, it seems natural to ask, does the energy associated with life
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go when we die?
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The trick is to think of life as a process rather than a substance. When a
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candle is burning, there is a flame that clearly carries energy. When we put
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the candle out, the energy doesn’t “go” anywhere. The candle still contains
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energy in its atoms and molecules. What happens, instead, is that the pro-
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cess of combustion has ceased. Life is like that: it’s not “stuff”; it’s a set of
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things happening. When that process stops, life ends.
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Life is a way of talking about a particular sequence of events taking place
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among atoms and molecules arranged in the right way. That wasn’t always
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so obvious; the nineteenth century saw the flowering of a doctrine known
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as vitalism, according to which life is associated with a certain kind of spark 12
or energy, labeled by French philosopher Henri Bergson as élan vital (life
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force). This idea has since gone the way of other similar nineteenth- century
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doctrines that posited new substances that we now recognize as simply ways
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of talking about the motions of ordinary matter. “Phlogiston,” for example,
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was supposed to be a kind of element that was contained within flammable
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bodies, and released during the process of combustion. Today we know that
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combustion is simply a rapid chemical reaction in which molecules com-
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bine with oxygen. Similarly, “caloric” was a hypothetical fluid that repre-
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sented the heat contained in a body, which would flow from hotter objects
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to colder ones. Now we understand heat as a measure of the energy con-
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tained in the random thermal motions of atoms and molecules.
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Over and over, something that we once thought of as a distinct kind of
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substance has been revealed to be a particular property of ordinary matter
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in motion. Life is no different.
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People have put forward direct evidence for life after death, in the form of
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near- death experiences or even cases of reincarnation. Often it is claimed
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that patients near death saw things that they couldn’t possibly have seen, or
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that young children remember events from past lives that they couldn’t
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have known about. Upon closer inspection, the large majority of such tes-
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timony proves to be less dramatic than originally suggested. One famous
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case is that of Alex Malarkey (his actual name, honest), who wrote the book
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The Boy Who Came Back from Heaven with his father, Kevin. After
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reaching bestseller status and being made into a TV movie, Alex admitted
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that his tale of visiting heaven and meeting Jesus during a near- death expe-
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rience was a thorough fabrication.
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No cases of claimed afterlife experiences have been subject to careful
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scientific protocols. People have tried; several studies have been conducted
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trying to find evidence for out-of-body experiences in patients who have
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near- death encounters. Researchers will visit hospital rooms and, without
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specific knowledge on the part of patients or medical staff, hide some kind
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of visual stimulus in a place where the patient would have to be floating
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freely of their own body to see it. To date, there has been no case where such
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a stimulus has been clearly seen.
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When judging the veracity of such claims, we need to weigh them
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against the scientific knowledge we have acquired in much more controlled
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conditions. It’s possible that the known laws of physics are dramatically
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wrong in such a way as to allow human consciousness to persist after the
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death of the physical body; however, it is also possible that people under the
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extreme conditions of nearly dying are likely to hallucinate, and that re-
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ports of prior lives are exaggerated or faked. Each of us must choose our
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priors and update our credences the best we can.
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It might seem wrongheaded to draw such sweeping conclusions about hu-
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man capacities and limitations from something as narrow and esoteric as
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quantum field theory. Quantum fields, however, are indisputably part of
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who we are. If they are all of who we are, we should have no problem draw-
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ing implications of that fact for our lives. If there is something in addition
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to the quantum fields, it is reasonable to seek an understanding of (and
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evidence for) that something that is just as precise and rigorous and repro-
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ducible as the one we have for field theory.
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If we are collections of interacting quantum fields, the implications are
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enormous. It’s not just that we can’t bend spoons, and not even that our
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lives truly end when we die. The laws of physics governing those fields are
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resolutely impersonal and non- teleological. Our status as parts of the phys-
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ical universe implies that there is no overarching purpose to human lives, at
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least not any inherent in the universe beyond ourselves. The very notion of
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a “person” is ultimately a way of talking about certain aspects of the
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underlying reality. It’s a good way of talking, and we have good reason to
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take seriously all of the ramifications of that description, including the fact
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that human beings have individual purposes and can make decisions for
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themselves. It’s when we start imagining powers or behaviors that contra-