Reductionism, Emergence, Leptons, and Bushmen

“All science is either physics or stamp collecting”

In an anthropology class I took in college, we had a particularly riveting discussion. It had nothing to do with anthropology. Yet everything to do with anthropology.

We had a wonderful professor. Unlike some of the faculty, she was a skilled teacher, not just an expert in her field. In one class, I don’t recall how, we got on the subject of reductionism. To her credit, she not only allowed, but as I recall initiated, this unorthodox departure from the syllabus.

Reductionism is nuanced and messy. There are multiple types. What we talked about in anthropology class all those years ago was methodological reductionism. Wikipedia defines this as “the scientific attempt to provide an explanation in terms of ever-smaller entities.”

It’s not surprising we landed on this topic. I went to a liberal arts school. Students took courses in a variety of subjects across the humanities, social sciences, and natural sciences. Fields within social and natural sciences study the world at different levels. For that matter, humanities do too.

Consider anthropology, biology, chemistry, and physics.

• Anthropology is the study of humanity, including behavior, biology, society, culture, and linguistics.
• Biology is the study of life. Humans are one of many life forms.
• Chemistry is the study of matter and energy, with a focus on how substances interact. At the core of chemistry are atomic elements. Life is made up of such elements, primarily carbon.
• Physics is the study of fundamental principles of physical phenomena, including matter, energy, and dimensions like space and time. It deals with the world at a macro level, like astrophysics, but also the smallest possible micro levels, like sub-atomic particles. Chemistry stops at the atom. Physics descends not only to sub-atomic particles but, as some physicists theorize, strings that span 10 to 26 dimensions and whose vibrational states we perceive as sub-atomic particles.

Physics seems to be at the root of everything. This is what provoked Ernest Rutherford — the 1908 Nobel Prize winner and widely acknowledged “father” of nuclear physics — to declare, “All science is either physics or stamp collecting.”

Theologians might have a bone to pick with that bon mot. Does physics provide ultimate root causes? Or does God, at least for those who so believe?

At a liberal arts college, the faculty spans many disciplines. It’s natural to assume professors have varying opinions, depending on their field, about what level of study is the most fruitful.

Consider the Kalahari Bushmen, nomadic hunter-gatherers who live in southern Africa. Is their chosen lifestyle a function of culture? Or the inevitable results of the biological ecosystem where they live?

But a biological ecosystem is a function of chemical reactions. Does it make sense to consider chemical reactions as the root cause of the Kalahari lifestyle?

Chemical reactions, in turn, are a function of sub-atomic particle behavior. Is physics the appropriate field to explain the Bushmen’s lifestyle?

Prima facie, this is absurd. How can physics contribute anything useful to understanding the lifestyle of Kalahari Bushmen? The reason this seems silly is emergence. According to Wikipedia “emergence occurs when a complex entity has properties or behaviors that its parts do not have on their own, and emerge only when they interact in a wider whole.”

Sub-atomic particles like quarks and leptons may be fascinating, but because of emergence, you can’t learn much about nomadic lifestyles by studying fragments produced by a super collider.

Rutherford’s comment implies that only physics studies root causes. The rest of science only organizes bits of knowledge. It’s a seductive, yet erroneously reductive notion, and because of emergence, a false one. Human culture is emergent. It’s a system that cannot be understood by looking through an electron microscope.

But as powerful as emergence is, it’s not a magic wand that eliminates the problem posed by reductionism. While studying neutrinos won’t tell you much about the Kalahari Bushmen, studying the biological ecosystem in which they live very well might. Or is culture the driving force that defines this ethnic group? Should you study both?

Our universe is not carved up neatly like the departments in a college course catalog. Outside of the human mind, there’s no such thing as physics. It’s an abstract concept we use to impose an artificial boundary around a field of study. This is also true of chemistry, biology, anthropology, Hispanic studies, Arabic literature, behavioral economics, African history, and fashion design.

There’s still a conundrum here. Consider software engineering. When a bug is found, a software engineer is assigned to fix it. Typically, the engineer will try to find the root cause. But that term’s nebulous. If I isolate the problem to a particular function and then replace that function with a different one, have I found root cause?

Most software engineers would call bullshit. Avoiding the function is a hack, a workaround. Don’t be lazy. Find the specific line(s) of code that cause the problem.

But what is magical about a line of code in a higher-level programming language like Java? After all, a Java compiler produces what is called byte code, and often, a Java Virtual Machine compiles bytecode into machine code, which is the level of instructions a processor understands.

Of course, machine code is really a series of binary digits, which in turn are electrical charges, and those in turn are a function of atomic particles, and so on.

But the vast majority of the time, there’s no value in looking at anything below higher level Java statements, because it’s assumed everything underneath “works.” It may not, of course. A computer board could be randomly flipping bits. But that’s pretty rare.

Once or twice a century, someone stuns the world, as Einstein did with his breathtaking integration of time and space in Special Relativity.

But mostly life is messy. It’s not surprising that there’s no magic formula which solves the conundrum of how deeply one should dig to understand a phenomenon. Any phenomenon. Like most things in life, deciding when to stop fishing and cut bait comes down to judgment and experience.

Early in this essay, I posed a theoretical conundrum about where to draw lines in understanding the nomadic Kalahari Bushmen lifestyle. But I think we face this problem daily.

Imagine a painful conversation with a co-worker. How you respond can range anywhere from “Jesus, that Larry is a flaming douchebag!” to spending an entire evening analyzing each line of the conversation to understand how things went askew.

You ought to reduce. Without some reduction, you live a life of superficial reactivity. But at some point, further reducing an emergent phenomenon is bringing coals to Newcastle. If you go too far, you might be studying leptons for clues about the lifestyle of Kalahari Bushmen.

Much of life is about seeing patterns. Reduction and emergence are patterns. Digging for root cause is a pattern. These patterns are worth seeing.

Many thanks to Patricia Jeanne for emerging as an editor and not reducing this piece to shreds!