October 22, 2023. Physicists say beauty--a sense of harmony, symmetry, rightness--guides them toward truth. But cognitive dissonance--an intuition of disharmony, wrongness--nudges me more reliably toward insight. And lately I’ve been feeling acute cognitive dissonance.

I’ve been reading the marvelous new book by physics journalist George Musser, Putting Ourselves Back in the Equation: Why Physicists Are Studying Human Consciousness and AI to Unravel the Secrets of the Universe. Musser is a superb explicator of scientific ideas. His 2015 book Spooky Action at a Distance is one of my favorite guides to quantum mysteries.

In Back in the Equation, Musser delves into attempts to explain how physical processes yield consciousness, perception, memory--all the stuff that makes up minds. I’ve tracked this research for so long I’m at risk of getting jaded. But Musser’s enthusiasm for matter-to-mind models is irresistible. He keeps telling me things I didn’t know and showing me things I thought I knew in a new light.

Cognitive dissonance strikes when I finish a chapter and compulsively check nytimes.com to see what fresh horror has erupted in the Middle East. I feel wrenched, torn, jumping from the latest theories of consciousness to the latest news from Gaza. The former seem utterly unrelated to the latter.

The mind-body problem, the focus of Musser’s book, can get dauntingly technical and abstract, but it comes down to a simple question: What are we? Theorists have come up with wildly diverse answers: We are a pack of entangled particles. A neural network. A grid of information-processing nodes. A Bayesian algorithm.

But there is a gap, no, an abyss, a cold interstellar void, between the theorizing in Back in the Equation and the messy, painful realities of human existence. My cognitive dissonance, my sense of wrongness, makes me suspect something is missing from mind-body research, something vitally important. What is it? What’s missing?

Here’s my stab at an answer. The mind-models described by Musser overlook a crucial feature of our existence, which is that we constantly face choices about what we should do. Call them should-choices. The stakes of should-choices are often low. Should I order a veggie-burger tonight, to appease my militantly vegetarian girlfriend, Emily? Or should I selfishly indulge my craving for a juicy beef burger?

In other cases, the stakes are very, very high. Think of the should-choices over which Israeli and Palestinian leaders are agonizing, as well as officials in the U.S., Europe, Lebanon, Iran, Egypt and elsewhere. Ordinary people around the world, not just Jews and Muslims, are asking themselves: What should I think about what’s happening? Should I speak up? Sign a petition? Join a protest? What if that means I might lose friends, or my job?

The premise of Musser’s book is that a theory of everything, to be worthy of the name, must encompass mind as well as matter. I propose going further: a theory of everything should have something to say about should-choices, which have no place in conventional physics.

Your theory of everything doesn’t have to tell us how to resolve should-choices. That’s far too much to ask, given that philosophers have failed despite millennia of effort to agree on how we should behave. Intellectuals still bicker over whether killing children is permissible under certain circumstances. Militant groups seeking political legitimacy kill kids, and so do nation-states, including my own country.

But your theory of everything should allow for what could be called should-causation, whereby human perceptions of what should be translate into choices with physical consequences. Should-causation is vastly more complicated than conventional physical causation. Think of the difference between the detonation of an atomic bomb and the decision to drop it.

Should-causation requires not only consciousness but also free will, which I define as our capacity to discern and choose among different paths; as well as some sort of system for designating actions as good and bad, right and wrong, just and unjust.

You might reasonably respond that physics can only inform us about what is, not what should be. But leading mind-body theorists, Musser notes in Back in the Equation, not just acid heads and meditators, contend that mind is more fundamental than matter. And rather than being the exclusive property of a few brainy terrestrial species, consciousness pervades the entire cosmos. Supposedly.

Could free will be fundamental too? And perhaps a cosmic moral order that tips choices in a certain direction? Nah. Imputing mind-based properties to the universe strikes me as too anthropocentric, and religious. But if should-choices are not fundamental to existence as a whole, they are certainly fundamental to our existence.

Common sense tells me the capacity for making should-choices emerged relatively recently in human evolution, in tandem, perhaps, with a capacity for language, self-awareness and moral reflection. Evolutionary biologists, notably Robert Trivers, hypothesize that natural selection instilled altruistic impulses, along with a sense of fairness, in our ancestors. Do baboons or bumblebees or other organisms make should-choices, too? I have no idea, but we humans clearly do.

A final point. A theory of everything, at the very least, should not rule out the possibility of should-driven causation. And yet some mind-body theorists, Musser reports, reject free will and even the whole notion of causation.

When I encountered these passages of Back in the Equation, my cognitive dissonance shrieked like an air-raid siren. For weeks, bullets and missiles have been flying in the Middle East, and many children have ended up dead. You’re saying no one really chose to fire those bullets or launch those missiles, and those decisions didn’t really cause the deaths of those kids?

If that’s what your theory of everything implies, then fuck your theory of everything. Next you’ll be telling me that injustice, oppression and suffering aren’t real either, because they don’t show up in your equations.

Postscript: Wednesday November 1, 4-5 PM EST, I’m having a zoom chat with neurobiologist Robert Sapolsky about his new book Determined: A Science of Life without Free Will. Here is the link: https://stevens.zoom.us/j/92641873233.

Further Reading:

The End of War

Where Is Outcry Over Children Killed by U.S.-Led Forces?

You’re Not Free If You’re Dead: The Case Against Giving Ukraine F-16s

My Slam-Dunk Arguments for Free Will

I explore possible connections between physics and social justice in a chapter of My Quantum Experiment titled “I Understand That I Can’t Understand.”

For more on consciousness, free will, morality and other mysteries of mind, see Mind-Body Problems, subtitled Science, Subjectivity & Who We Really Are.