Calibration until compliant: Why unlimited free parameters in ABM risk producing tautologies instead of social insight

TL;DR: Computational models are only scientifically useful if they can push back and prove their authors wrong. Across disciplines, from agent-based social simulations to high-energy physics, models with loose empirical feedback loops and endless free parameters risk becoming "decorative." Instead of testing reality, they get calibrated until compliant, turning a tool for discovery into a self-confirming tautology. Honest modeling requires radical transparency, sensitivity testing, and explicit criteria for failure before running the simulation.

I build models for a living. Specifically, molecular dynamics. These are simulations that track how thousands or millions of atoms move, collide, and rearrange over time, used for everything from drug design to materials science.

Here is the story scientists usually tell. If a model is wrong, you find out quickly. Reality does not care about your assumptions. The atoms do not read your code. If the physics you programmed in is wrong, the simulation produces garbage, the experiment disagrees, and you go back and fix it. The feedback loop between model and world is short, brutal, and non-negotiable.

That story is not entirely true. I know, because I have watched it fail from the inside.

The most important choice in any molecular dynamics simulation is not the code, the computer, or the software. It is the potential function, the mathematical formula that describes how strongly every pair of atoms attracts or repels each other. Everything the simulation does follows from that one ingredient. Get it right and the model can tell you something real. Get it wrong and you have made a very expensive mistake.

And here is the uncomfortable part. In practice, it is far more often inherited than audited. Potentials are chosen by looking at what previous papers in the subfield used. A potential gets published, cited, copied, and passed down until it stops being a modeling choice and becomes a tradition. People run simulations for years without asking whether the potential they inherited was ever validated for the system they are studying, at the conditions they are studying it, for the property they care about.

So even in my own field, a hard, quantitative, physics-based field, you can publish inside a loop of fantasy. Models that are wrong in ways nobody checks, kept alive by citation habits and subfield convention. And because these errors travel quietly across subdisciplines and into interdisciplinary work, where nobody feels responsible for checking them, finding one and fixing it takes real effort.

But the check in my field is delayed, not absent. A bad potential eventually unfolds a simulated protein the wrong way or fails a material in a real engineering application, and someone notices. In much of the modeling I am about to describe, the physical world never gets to vote.

This matters for what follows. I do not ask this question because my field got it right. I ask it because I have watched mine get it wrong. The question is always the same. What happens to this model when it is wrong?

In a surprising amount of modern academia, the answer is nothing. Nothing can happen to it. It cannot be wrong, because anything it produces counts as a result.

And if the loop can break in a field where atoms push back, it can break anywhere.

This essay is about how that happens.

# The magic trick

In 2017, Liane Gabora and Selin Tseng published a paper in *Psychology of Aesthetics, Creativity, and the Arts*, a peer-reviewed journal of the American Psychological Association, titled “The Social Benefits of Balancing Creativity and Imitation.” The question they took on has occupied historians and sociologists for centuries. What is the right balance of creativity and conformity in a society?

To answer it, they ran a simulation.

Virtual agents live on a grid. Some are coded as creators, inventing new ideas; others as imitators, copying their neighbors. A scoring rule written into the program decides which ideas count as good. The researchers ran the simulation forward, varied the ratio of creators to imitators, and watched what happened. Populations with too many creators ended up with fewer good ideas taking hold. The published conclusion was that society needs imitation as much as creativity, because unchecked creativity disrupts the spread of proven ideas.

I want to be careful about what I am claiming, because this paper is not fringe work. It passed peer review at a respectable journal. The authors are serious researchers, and the simulation framework behind the paper is part of a long-running research program that has been debated, defended, and criticized in public for years. Nothing I am about to say is an accusation of dishonesty. It is something less comfortable than that. This paper is an example of what the normal standards of a field allow through.

Watch the shape of the argument. Inside the model, a “good idea” means whatever the authors’ scoring rule rewards. The agents are not discovering anything about human culture; they are solving a puzzle whose answer key was fixed before the simulation started. Within that closed loop, the conclusion was guaranteed. A population of agents that mostly copies the scoring rule’s preferred ideas will always outcompete one that keeps generating unscored novelty.

The computer did not reveal a fact about creativity. It executed a definition of it.

The authors did not break any rule of their field. That is the point. Peer review checked that the code ran, that the statistics were computed correctly, that the prose matched the output. What nobody was required to ask is the only question that matters. What could this simulation possibly have shown that would have counted as the opposite result? If the answer is nothing, the model did not test a claim about the world. It restated one.

This is the magic trick of agent-based modeling (ABM), meaning simulations in which you place thousands of simple software “agents” in a virtual world, give each a few rules, and watch what the population does. The method itself is not the problem. The problem is a particular way of using it.

if neighbor.opinion != agent.opinion:

agent.trust -= 0.1

if agent.trust < 0.2:

agent.unfollow(neighbor)

run_simulation()

When the simulation finishes and the agents have sorted into two angry camps, the result is rarely described as what it literally is, a small program doing what it was told. It is described as a model demonstrating the dynamics of polarization in real societies.

It sounds scientific. It uses code. It generates charts with error bars. It borrows the epistemic authority of statistical mechanics and epidemiology, where tracking near-identical particles or infection events actually makes sense. But underneath the quantitative paint, it is not an investigation of the world. It is a tautology with a runtime, an answer-driven argument presented as a discovery.

# What a model is for

To see why this goes wrong, start with what a model is supposed to do.

A model is not a claim of truth, and it is not an illustration of a conclusion you reached before you started. In the philosophy of science, models are usually understood as instruments that sit between abstract theory and raw data, the position developed by Mary Morgan and Margaret Morrison in *Models as Mediators* (1999). A good model is a sandbox with strict physics. You build it, set it in motion, and let its internal mechanics push back against your reasoning.

A real model exists to discipline your thinking.

&gt;Building one forces you to acknowledge a trade-off that the philosopher Nancy Cartwright made famous in *How the Laws of Physics Lie* (1983). You trade complete literal truth for tractability. A map of London at 1:1 scale, including every brick, puddle, and commuter, is useless. To work at all, a map must leave almost everything out. As the statistician George Box put it, “all models are wrong, but some are useful.”

Simplification is not the sin. The sin is forgetting that the model is a simplification. Worse, it is turning the model into an accomplice.

# Disciplining vs. decorating

In practice, rigorous modeling and decorative modeling look identical from the outside. Same code, same charts, same jargon. The difference only shows when you ask one question. Can your model tell you that you are wrong?

A disciplining model forces you to state every assumption explicitly. Once running, its mechanics operate independently of what you want. It can produce behavior you did not expect, expose contradictions in your premises, or crash into empirical reality and fail. When it fails, you revise the theory. The model is a check on your own bias.

A decorating model is built backward from a conclusion. The researcher already knows the story. Suppose it is that polarization is driven by social contagion. They build a world in which agents swap beliefs, tune the parameters until the output shows two angry clusters, and present the code as evidence for the theory. If the output doesn’t match on the first run, the answer is not to abandon the hypothesis. The answer is to adjust agent\_receptivity from 0.4 to 0.25, rerun, and present the successful parameter range as the plan all along.

The workflow, stripped bare, looks like this.

Desired outcome. Write rules. Run simulation. Does it match the theory? If not, tweak parameters and run again. If yes, publish.

This is not experimentation. It is calibration until compliant.

If a model cannot surprise its author, force a retreat, or fail, it is not really a model. It is a very elaborate, self-confirming editorial.

# The conclusion comes first

None of this is new, and none of it is unique to agent-based modeling. Before anyone wrote a NetLogo script to demonstrate a theory of culture, economics and political science had already industrialized the technique.

In 2015, Paul Romer, later a Nobel laureate, published a paper with the blunt title “Mathiness in the Theory of Economic Growth.” His target was a pattern in macroeconomic theory. Authors write down formal equilibrium models, but embed ideologically convenient assumptions inside obscure parameters, so that the math reliably outputs the desired policy conclusion. The mathematics is not being used to test whether a claim is true. It is being used to make a political position expensive to argue with. Checking whether the equations actually say what the surrounding prose claims they say takes serious technical effort, and reviewers routinely skip it.

Two decades earlier, the political scientists Donald Green and Ian Shapiro published *Pathologies of Rational Choice Theory* (1994), documenting how formal modeling in their field had become an exercise in self-confirmation. Their catalog of evasions maps one-to-one onto today’s agent-based simulations.

• **Post hoc tinkering.** When the model predicted that rational citizens would never vote (the individual cost exceeds any plausible benefit) and citizens kept voting anyway, theorists did not abandon the model. They added a “duty” term to the utility function until the math matched the turnout.

• **Arbitrary tuning.** Weights, thresholds, and interaction ranges adjusted on the fly until the simulated agents behave like the phenomenon under study.

• **Immunity to testing.** Models built so that every conceivable outcome can be reinterpreted, after the fact, as a rational equilibrium.

Green and Shapiro called this method-driven rather than problem-driven research. You start with a tool and go hunting for a reality that fits it.

Agent-based modeling makes the problem worse, for a simple reason. An ABM has almost unlimited free parameters. Every rule, threshold, and neighborhood radius is a dial. With enough dials, you can produce any curve you want.

The common structure is this. The model cannot fail, because failure is reclassified as a calibration bug. And a model that cannot fail cannot discover anything. It is an expensive echo of its author’s prior beliefs.

# The loop matters more than the lab coat

It would be comfortable to stop here and declare this a disease of the soft sciences. It isn’t. The hard sciences are not immune, and pretending otherwise would make this essay guilty of the same simplification it criticizes.

The real variable is not hard versus soft. It is the tightness of the feedback loop between the model and the world.

Where the loop is tight (fast experiments, unambiguous ground truth, few free parameters) bad modeling gets punished quickly. But where the loop is loose, where tests are slow, noisy, or impossible, the same decorative pathology appears in fields with particle accelerators.

Three documented examples.

**fMRI neuroscience, where the measurement is the model.** A brain scan shows blood flow, not thought. The colored images come from a statistical pipeline full of assumptions, and researchers once demonstrated what that means by detecting “brain activity” in a dead salmon. In 2016, Anders Eklund and colleagues showed that the standard methods in the field’s dominant software could produce false-positive rates of up to 70 percent for certain cluster-based analyses at particular thresholds. How far the problem extends across the published literature was contested, including in follow-up work by the authors themselves, but the core finding stood. For over a decade, the field’s feedback loop had run through that software, which meant the loop was not connected to reality at all.

**Fundamental physics, where experiment cannot keep up.** In *The Trouble with Physics* (2006), the physicist Lee Smolin, writing as an insider, argued that string theory had become flexible enough to accommodate any experimental outcome. When the Large Hadron Collider found no sign of supersymmetry, much of the field responded not with refutation but with retreat. The free parameters moved to heavier, less accessible energies. This is Green and Shapiro’s immunity to empirical testing, surfacing in the hardest science there is.

**Epidemiological modeling in 2020.** In the spring of 2020, influential models, including the one from Imperial College London that helped push governments toward lockdown, projected enormous death tolls based on weeks of noisy early data. When later estimates came down, the public response from modeling teams was recalibration rather than reckoning. Their defense deserves to be taken seriously. The projections were scenarios, not forecasts, and the point of publishing a worst case was to change behavior so that it would not come true. A warning that works cannot be graded on whether the disaster arrived. All of that is fair, and it is also the problem. A model whose failure can always be explained by the world changing in response to it is a model with no feedback loop, and the field never settled which of the two it had built.

Notice what these cases share with the creativity grid from the opening. Not the field. Not the math. The structure. Many free parameters, a loose or broken feedback loop, and a professional incentive to publish. Given those three, decorative modeling can appear anywhere. The loop matters more than the lab coat.

# Why it’s still worse in the humanities

So the hard sciences have their own decorative modeling. Why do I still think the problem is worse in the humanities?

Because the difference is not whether a field ever decorates. It is whether the field *can catch itself*. The fMRI problem was eventually found and published by neuroscientists. Smolin’s critique came from inside physics. The feedback loops in the hard sciences are sometimes slow or broken, but they exist, and there are people with the technical skill and the standing to pull on them. In the humanities’ version of modeling, three structural failures mean the loop often doesn’t exist at all. The difference is not that humanists are worse at modeling. It is that the auditing infrastructure barely exists.

It is worth being fair about why scholars reach for these tools in the first place. Humanities departments face shrinking budgets, declining enrollments, and university administrators who mistake mathematical notation for intellectual rigor. A computational model signals seriousness to a grant committee in a way an essay never can. The scholars building decorative models are not fools; they are rational actors navigating a system with broken incentives.

**The object of study resists formalization.** A water molecule behaves like a water molecule in London or Tokyo, in 1600 or today. It has no irony, no memory, no politics. Human culture has all three. A novel, a religious movement, an aesthetic shift cannot be reduced to a set of isolated rules without destroying part of what you set out to study. When you convert the reception of Victorian gothic fiction into agents swapping “gothic preference points,” you have not simplified the system for tractability. You have replaced it with something simpler that carries the same name. At that point the connection between the simulation and Victorian readers is no longer something the model establishes. It is something the reader is asked to assume.

**Construct validity is invented, not established.** In psychology, showing that a variable actually measures the concept it claims to measure (construct validity) is a slow, adversarial, decades-long process. Blood flow is at least a physical quantity that an instrument can register. There is no instrument for literary prestige. In humanities modeling, validity is routinely settled in one line of code.

self.piety = random.uniform(0.0, 1.0)

self.literary_prestige = 0.75

What does 0.75 mean for literary prestige in Victorian England? How does one number carry regional difference, class, institutional power, critical backlash, and retrospective canonization? It doesn’t. The modeler assigns a number, writes a function that nudges it up and down, and treats the variable as a measurement of human experience. The number looks like a measurement. Nothing underneath it has been measured.

**The audience cannot audit the compression.** When an epidemiologist shows a flawed model to epidemiologists, the reviewers share the vocabulary to check the code and challenge the parameters. In a humanities department, reviewers and readers often have no computational training. Presented with a grid of moving pixels and a network graph, the non-technical reader experiences an optical illusion. The machine appears to have performed a profound synthesis of the archive. The compression is lossy to the point of erasure. But the loss is buried in code, invisible to the exact audience responsible for evaluating the work.

Bad modeling in economics wastes grant money and distorts policy debates. Bad modeling in the humanities trades away the field’s actual strength (context, contingency, ambiguity, close reading, historical depth) for a seat at a quantitative table where, lacking the shared technical culture to enforce standards, it gains no real authority and surrenders its own.

# What honest modeling looks like

None of this is an argument for unplugging the computers. The goal is to tell the difference between decorative simulation and honest quantitative work. Honest work exists, including in the humanities.

Ted Underwood’s *Distant Horizons* (2019) is the standard I would hold up. Underwood uses quantitative methods on tens of thousands of digitized books not to declare causal laws but to surface patterns invisible to close reading, like slow shifts in genre, vocabulary, and narrative perspective across centuries. Crucially, he tells you, on the record, what the data cannot show. The model is a set of binoculars for looking across an archive, not a machine for generating verdicts about it.

And the humanities have produced their own internal discipline. In 2019, Nan Z. Da published, *The Computational Case against Computational Literary Studies,* a detailed critique in *Critical Inquiry* arguing that prominent work in computational literary studies misused statistics to the point of meaninglessness. The ensuing fight was heated, but it happened. The field argued about its standards in public, and the standards moved. That is what a functioning feedback loop looks like, even a slow and painful one.

&gt;For modelers in any field, I would propose four non-negotiable conditions before a model earns the right to be cited as evidence.

**1. Radical transparency**

&gt;Every parameter is declared and justified with independent, non-circular evidence. A variable you cannot justify is labeled what it is. A guess.

**2. Sensitivity analysis**

&gt;Parameters are swept across their full plausible range. If your result only appears when three dials sit at hyper-precise decimal values, you have not found a law of history. You have found a brittle corner of your own code, and an honest paper should say so.

**3. Explicit exclusion mapping**

&gt;You spend nearly as much space on what the model leaves out as on what it includes. This isolates the direct mechanical relationship between two variables under idealized conditions; it excludes ambient noise, structural heterogeneity, and systemic feedback, so it cannot predict specific real-world outcomes. Naming the exclusions is what stops the audience mistaking a sandbox for an account of the world.

**4. Capacity for failure**

&gt;Before you run it, you can state what output would make you abandon your hypothesis. If the simulation contradicts you, the honest paper is titled “Why our model disproved our starting assumption,” not silently recalibrated into agreement.

Models built this way stop being decoration. They become what they were supposed to be. Sharpening stones. They force you to clarify assumptions, expose broken logic, and occasionally reveal dynamics that intuition would never find.

# The boundary question

The target of this essay was never the computer. Built with discipline, models are extraordinary instruments. I have staked my own career on that. What concerns me is how easily a model can be built to confirm rather than to question, and how hard it is for a reader to tell the difference from the outside.

The practice corrupts both traditions it sits between.

It corrupts science, because science is not the production of plots and code. It is the submission of claims to the risk of being wrong. A model engineered so that its parameters are tuned until the output matches the thesis offers the aesthetics of rigor with none of its discipline.

And it corrupts the humanities, because the study of human culture draws its value from exactly the things decorative modeling deletes. Context, contingency, ambiguity, power, the irreducible strangeness of actual human lives.

If a phenomenon is too context-bound, too polysemic, too alive to be captured by a set of if statements, we should have the courage to say so, and do the slow, unglamorous work of interpretation instead.

I keep coming back to the question I ask of every model, including my own. What happens to you when you are wrong?

For my models, the answer is supposed to be easy. The crystal melts. The experiment disagrees. Reality sends the bill. But only if someone checks the potential, and I have told you how often that happens.

For the models I’ve described here, the answer is nothing. They run, they publish, they are cited. The loop that is supposed to connect a model to the world was never closed.

*Which raises the question I can’t answer. If a model can never be wrong about the world, in what sense was it ever about the world?*

[](https://www.reddit.com/submit/?source\_id=t3\_1wxoo7n&composer\_entry=crosspost\_prompt)

reddit.com
u/Capital-Elephant9431 — 10 days ago

Disciplining vs. Decorating: Why models without real-world feedback loops just calibrate to fit the narrative

TL;DR: Computational models are only scientifically useful if they can push back and prove their authors wrong. Across disciplines, from agent-based social simulations to high-energy physics, models with loose empirical feedback loops and endless free parameters risk becoming "decorative." Instead of testing reality, they get calibrated until compliant, turning a tool for discovery into a self-confirming tautology. Honest modeling requires radical transparency, sensitivity testing, and explicit criteria for failure before running the simulation.

I build models for a living. Specifically, molecular dynamics. These are simulations that track how thousands or millions of atoms move, collide, and rearrange over time, used for everything from drug design to materials science.

Here is the story scientists usually tell. If a model is wrong, you find out quickly. Reality does not care about your assumptions. The atoms do not read your code. If the physics you programmed in is wrong, the simulation produces garbage, the experiment disagrees, and you go back and fix it. The feedback loop between model and world is short, brutal, and non-negotiable.

That story is not entirely true. I know, because I have watched it fail from the inside.

The most important choice in any molecular dynamics simulation is not the code, the computer, or the software. It is the potential function, the mathematical formula that describes how strongly every pair of atoms attracts or repels each other. Everything the simulation does follows from that one ingredient. Get it right and the model can tell you something real. Get it wrong and you have made a very expensive mistake.

And here is the uncomfortable part. In practice, it is far more often inherited than audited. Potentials are chosen by looking at what previous papers in the subfield used. A potential gets published, cited, copied, and passed down until it stops being a modeling choice and becomes a tradition. People run simulations for years without asking whether the potential they inherited was ever validated for the system they are studying, at the conditions they are studying it, for the property they care about.

So even in my own field, a hard, quantitative, physics-based field, you can publish inside a loop of fantasy. Models that are wrong in ways nobody checks, kept alive by citation habits and subfield convention. And because these errors travel quietly across subdisciplines and into interdisciplinary work, where nobody feels responsible for checking them, finding one and fixing it takes real effort.

But the check in my field is delayed, not absent. A bad potential eventually unfolds a simulated protein the wrong way or fails a material in a real engineering application, and someone notices. In much of the modeling I am about to describe, the physical world never gets to vote.

This matters for what follows. I do not ask this question because my field got it right. I ask it because I have watched mine get it wrong. The question is always the same. What happens to this model when it is wrong?

In a surprising amount of modern academia, the answer is nothing. Nothing can happen to it. It cannot be wrong, because anything it produces counts as a result.

And if the loop can break in a field where atoms push back, it can break anywhere.

This essay is about how that happens.

The magic trick

In 2017, Liane Gabora and Selin Tseng published a paper in Psychology of Aesthetics, Creativity, and the Arts, a peer-reviewed journal of the American Psychological Association, titled “The Social Benefits of Balancing Creativity and Imitation.” The question they took on has occupied historians and sociologists for centuries. What is the right balance of creativity and conformity in a society?

To answer it, they ran a simulation.

Virtual agents live on a grid. Some are coded as creators, inventing new ideas; others as imitators, copying their neighbors. A scoring rule written into the program decides which ideas count as good. The researchers ran the simulation forward, varied the ratio of creators to imitators, and watched what happened. Populations with too many creators ended up with fewer good ideas taking hold. The published conclusion was that society needs imitation as much as creativity, because unchecked creativity disrupts the spread of proven ideas.

I want to be careful about what I am claiming, because this paper is not fringe work. It passed peer review at a respectable journal. The authors are serious researchers, and the simulation framework behind the paper is part of a long-running research program that has been debated, defended, and criticized in public for years. Nothing I am about to say is an accusation of dishonesty. It is something less comfortable than that. This paper is an example of what the normal standards of a field allow through.

Watch the shape of the argument. Inside the model, a “good idea” means whatever the authors’ scoring rule rewards. The agents are not discovering anything about human culture; they are solving a puzzle whose answer key was fixed before the simulation started. Within that closed loop, the conclusion was guaranteed. A population of agents that mostly copies the scoring rule’s preferred ideas will always outcompete one that keeps generating unscored novelty.

The computer did not reveal a fact about creativity. It executed a definition of it.

The authors did not break any rule of their field. That is the point. Peer review checked that the code ran, that the statistics were computed correctly, that the prose matched the output. What nobody was required to ask is the only question that matters. What could this simulation possibly have shown that would have counted as the opposite result? If the answer is nothing, the model did not test a claim about the world. It restated one.

This is the magic trick of agent-based modeling (ABM), meaning simulations in which you place thousands of simple software “agents” in a virtual world, give each a few rules, and watch what the population does. The method itself is not the problem. The problem is a particular way of using it.

if neighbor.opinion != agent.opinion:
 agent.trust -= 0.1
if agent.trust &lt; 0.2:
 agent.unfollow(neighbor)
run_simulation()

When the simulation finishes and the agents have sorted into two angry camps, the result is rarely described as what it literally is, a small program doing what it was told. It is described as a model demonstrating the dynamics of polarization in real societies.

It sounds scientific. It uses code. It generates charts with error bars. It borrows the epistemic authority of statistical mechanics and epidemiology, where tracking near-identical particles or infection events actually makes sense. But underneath the quantitative paint, it is not an investigation of the world. It is a tautology with a runtime, an answer-driven argument presented as a discovery.

What a model is for

To see why this goes wrong, start with what a model is supposed to do.

A model is not a claim of truth, and it is not an illustration of a conclusion you reached before you started. In the philosophy of science, models are usually understood as instruments that sit between abstract theory and raw data, the position developed by Mary Morgan and Margaret Morrison in Models as Mediators (1999). A good model is a sandbox with strict physics. You build it, set it in motion, and let its internal mechanics push back against your reasoning.

A real model exists to discipline your thinking.

>Building one forces you to acknowledge a trade-off that the philosopher Nancy Cartwright made famous in How the Laws of Physics Lie (1983). You trade complete literal truth for tractability. A map of London at 1:1 scale, including every brick, puddle, and commuter, is useless. To work at all, a map must leave almost everything out. As the statistician George Box put it, “all models are wrong, but some are useful.”

Simplification is not the sin. The sin is forgetting that the model is a simplification. Worse, it is turning the model into an accomplice.

Disciplining vs. decorating

In practice, rigorous modeling and decorative modeling look identical from the outside. Same code, same charts, same jargon. The difference only shows when you ask one question. Can your model tell you that you are wrong?

A disciplining model forces you to state every assumption explicitly. Once running, its mechanics operate independently of what you want. It can produce behavior you did not expect, expose contradictions in your premises, or crash into empirical reality and fail. When it fails, you revise the theory. The model is a check on your own bias.

A decorating model is built backward from a conclusion. The researcher already knows the story. Suppose it is that polarization is driven by social contagion. They build a world in which agents swap beliefs, tune the parameters until the output shows two angry clusters, and present the code as evidence for the theory. If the output doesn’t match on the first run, the answer is not to abandon the hypothesis. The answer is to adjust agent_receptivity from 0.4 to 0.25, rerun, and present the successful parameter range as the plan all along.

The workflow, stripped bare, looks like this.

Desired outcome. Write rules. Run simulation. Does it match the theory? If not, tweak parameters and run again. If yes, publish.

This is not experimentation. It is calibration until compliant.

If a model cannot surprise its author, force a retreat, or fail, it is not really a model. It is a very elaborate, self-confirming editorial.

The conclusion comes first

None of this is new, and none of it is unique to agent-based modeling. Before anyone wrote a NetLogo script to demonstrate a theory of culture, economics and political science had already industrialized the technique.

In 2015, Paul Romer, later a Nobel laureate, published a paper with the blunt title “Mathiness in the Theory of Economic Growth.” His target was a pattern in macroeconomic theory. Authors write down formal equilibrium models, but embed ideologically convenient assumptions inside obscure parameters, so that the math reliably outputs the desired policy conclusion. The mathematics is not being used to test whether a claim is true. It is being used to make a political position expensive to argue with. Checking whether the equations actually say what the surrounding prose claims they say takes serious technical effort, and reviewers routinely skip it.

Two decades earlier, the political scientists Donald Green and Ian Shapiro published Pathologies of Rational Choice Theory (1994), documenting how formal modeling in their field had become an exercise in self-confirmation. Their catalog of evasions maps one-to-one onto today’s agent-based simulations.

• Post hoc tinkering. When the model predicted that rational citizens would never vote (the individual cost exceeds any plausible benefit) and citizens kept voting anyway, theorists did not abandon the model. They added a “duty” term to the utility function until the math matched the turnout.

• Arbitrary tuning. Weights, thresholds, and interaction ranges adjusted on the fly until the simulated agents behave like the phenomenon under study.

• Immunity to testing. Models built so that every conceivable outcome can be reinterpreted, after the fact, as a rational equilibrium.

Green and Shapiro called this method-driven rather than problem-driven research. You start with a tool and go hunting for a reality that fits it.

Agent-based modeling makes the problem worse, for a simple reason. An ABM has almost unlimited free parameters. Every rule, threshold, and neighborhood radius is a dial. With enough dials, you can produce any curve you want.

The common structure is this. The model cannot fail, because failure is reclassified as a calibration bug. And a model that cannot fail cannot discover anything. It is an expensive echo of its author’s prior beliefs.

The loop matters more than the lab coat

It would be comfortable to stop here and declare this a disease of the soft sciences. It isn’t. The hard sciences are not immune, and pretending otherwise would make this essay guilty of the same simplification it criticizes.

The real variable is not hard versus soft. It is the tightness of the feedback loop between the model and the world.

Where the loop is tight (fast experiments, unambiguous ground truth, few free parameters) bad modeling gets punished quickly. But where the loop is loose, where tests are slow, noisy, or impossible, the same decorative pathology appears in fields with particle accelerators.

Three documented examples.

fMRI neuroscience, where the measurement is the model. A brain scan shows blood flow, not thought. The colored images come from a statistical pipeline full of assumptions, and researchers once demonstrated what that means by detecting “brain activity” in a dead salmon. In 2016, Anders Eklund and colleagues showed that the standard methods in the field’s dominant software could produce false-positive rates of up to 70 percent for certain cluster-based analyses at particular thresholds. How far the problem extends across the published literature was contested, including in follow-up work by the authors themselves, but the core finding stood. For over a decade, the field’s feedback loop had run through that software, which meant the loop was not connected to reality at all.

Fundamental physics, where experiment cannot keep up. In The Trouble with Physics (2006), the physicist Lee Smolin, writing as an insider, argued that string theory had become flexible enough to accommodate any experimental outcome. When the Large Hadron Collider found no sign of supersymmetry, much of the field responded not with refutation but with retreat. The free parameters moved to heavier, less accessible energies. This is Green and Shapiro’s immunity to empirical testing, surfacing in the hardest science there is.

Epidemiological modeling in 2020. In the spring of 2020, influential models, including the one from Imperial College London that helped push governments toward lockdown, projected enormous death tolls based on weeks of noisy early data. When later estimates came down, the public response from modeling teams was recalibration rather than reckoning. Their defense deserves to be taken seriously. The projections were scenarios, not forecasts, and the point of publishing a worst case was to change behavior so that it would not come true. A warning that works cannot be graded on whether the disaster arrived. All of that is fair, and it is also the problem. A model whose failure can always be explained by the world changing in response to it is a model with no feedback loop, and the field never settled which of the two it had built.

Notice what these cases share with the creativity grid from the opening. Not the field. Not the math. The structure. Many free parameters, a loose or broken feedback loop, and a professional incentive to publish. Given those three, decorative modeling can appear anywhere. The loop matters more than the lab coat.

Why it’s still worse in the humanities

So the hard sciences have their own decorative modeling. Why do I still think the problem is worse in the humanities?

Because the difference is not whether a field ever decorates. It is whether the field can catch itself. The fMRI problem was eventually found and published by neuroscientists. Smolin’s critique came from inside physics. The feedback loops in the hard sciences are sometimes slow or broken, but they exist, and there are people with the technical skill and the standing to pull on them. In the humanities’ version of modeling, three structural failures mean the loop often doesn’t exist at all. The difference is not that humanists are worse at modeling. It is that the auditing infrastructure barely exists.

It is worth being fair about why scholars reach for these tools in the first place. Humanities departments face shrinking budgets, declining enrollments, and university administrators who mistake mathematical notation for intellectual rigor. A computational model signals seriousness to a grant committee in a way an essay never can. The scholars building decorative models are not fools; they are rational actors navigating a system with broken incentives.

The object of study resists formalization. A water molecule behaves like a water molecule in London or Tokyo, in 1600 or today. It has no irony, no memory, no politics. Human culture has all three. A novel, a religious movement, an aesthetic shift cannot be reduced to a set of isolated rules without destroying part of what you set out to study. When you convert the reception of Victorian gothic fiction into agents swapping “gothic preference points,” you have not simplified the system for tractability. You have replaced it with something simpler that carries the same name. At that point the connection between the simulation and Victorian readers is no longer something the model establishes. It is something the reader is asked to assume.

Construct validity is invented, not established. In psychology, showing that a variable actually measures the concept it claims to measure (construct validity) is a slow, adversarial, decades-long process. Blood flow is at least a physical quantity that an instrument can register. There is no instrument for literary prestige. In humanities modeling, validity is routinely settled in one line of code.

self.piety = random.uniform(0.0, 1.0)
self.literary_prestige = 0.75

What does 0.75 mean for literary prestige in Victorian England? How does one number carry regional difference, class, institutional power, critical backlash, and retrospective canonization? It doesn’t. The modeler assigns a number, writes a function that nudges it up and down, and treats the variable as a measurement of human experience. The number looks like a measurement. Nothing underneath it has been measured.

The audience cannot audit the compression. When an epidemiologist shows a flawed model to epidemiologists, the reviewers share the vocabulary to check the code and challenge the parameters. In a humanities department, reviewers and readers often have no computational training. Presented with a grid of moving pixels and a network graph, the non-technical reader experiences an optical illusion. The machine appears to have performed a profound synthesis of the archive. The compression is lossy to the point of erasure. But the loss is buried in code, invisible to the exact audience responsible for evaluating the work.

Bad modeling in economics wastes grant money and distorts policy debates. Bad modeling in the humanities trades away the field’s actual strength (context, contingency, ambiguity, close reading, historical depth) for a seat at a quantitative table where, lacking the shared technical culture to enforce standards, it gains no real authority and surrenders its own.

What honest modeling looks like

None of this is an argument for unplugging the computers. The goal is to tell the difference between decorative simulation and honest quantitative work. Honest work exists, including in the humanities.

Ted Underwood’s Distant Horizons (2019) is the standard I would hold up. Underwood uses quantitative methods on tens of thousands of digitized books not to declare causal laws but to surface patterns invisible to close reading, like slow shifts in genre, vocabulary, and narrative perspective across centuries. Crucially, he tells you, on the record, what the data cannot show. The model is a set of binoculars for looking across an archive, not a machine for generating verdicts about it.

And the humanities have produced their own internal discipline. In 2019, Nan Z. Da published, The Computational Case against Computational Literary Studies, a detailed critique in Critical Inquiry arguing that prominent work in computational literary studies misused statistics to the point of meaninglessness. The ensuing fight was heated, but it happened. The field argued about its standards in public, and the standards moved. That is what a functioning feedback loop looks like, even a slow and painful one.

>For modelers in any field, I would propose four non-negotiable conditions before a model earns the right to be cited as evidence.

1. Radical transparency

>Every parameter is declared and justified with independent, non-circular evidence. A variable you cannot justify is labeled what it is. A guess.

2. Sensitivity analysis

>Parameters are swept across their full plausible range. If your result only appears when three dials sit at hyper-precise decimal values, you have not found a law of history. You have found a brittle corner of your own code, and an honest paper should say so.

3. Explicit exclusion mapping

>You spend nearly as much space on what the model leaves out as on what it includes. This isolates the direct mechanical relationship between two variables under idealized conditions; it excludes ambient noise, structural heterogeneity, and systemic feedback, so it cannot predict specific real-world outcomes. Naming the exclusions is what stops the audience mistaking a sandbox for an account of the world.

4. Capacity for failure

>Before you run it, you can state what output would make you abandon your hypothesis. If the simulation contradicts you, the honest paper is titled “Why our model disproved our starting assumption,” not silently recalibrated into agreement.

Models built this way stop being decoration. They become what they were supposed to be. Sharpening stones. They force you to clarify assumptions, expose broken logic, and occasionally reveal dynamics that intuition would never find.

The boundary question

The target of this essay was never the computer. Built with discipline, models are extraordinary instruments. I have staked my own career on that. What concerns me is how easily a model can be built to confirm rather than to question, and how hard it is for a reader to tell the difference from the outside.

The practice corrupts both traditions it sits between.

It corrupts science, because science is not the production of plots and code. It is the submission of claims to the risk of being wrong. A model engineered so that its parameters are tuned until the output matches the thesis offers the aesthetics of rigor with none of its discipline.

And it corrupts the humanities, because the study of human culture draws its value from exactly the things decorative modeling deletes. Context, contingency, ambiguity, power, the irreducible strangeness of actual human lives.

If a phenomenon is too context-bound, too polysemic, too alive to be captured by a set of if statements, we should have the courage to say so, and do the slow, unglamorous work of interpretation instead.

I keep coming back to the question I ask of every model, including my own. What happens to you when you are wrong?

For my models, the answer is supposed to be easy. The crystal melts. The experiment disagrees. Reality sends the bill. But only if someone checks the potential, and I have told you how often that happens.

For the models I’ve described here, the answer is nothing. They run, they publish, they are cited. The loop that is supposed to connect a model to the world was never closed.

Which raises the question I can’t answer. If a model can never be wrong about the world, in what sense was it ever about the world?

reddit.com
u/Capital-Elephant9431 — 11 days ago

Construct validity and lossy compression: A practitioner's critique of computational modeling in the humanities

TL;DR: Computational models are only scientifically useful if they can push back and prove their authors wrong. Across disciplines, from agent-based social simulations to high-energy physics, models with loose empirical feedback loops and endless free parameters risk becoming "decorative." Instead of testing reality, they get calibrated until compliant, turning a tool for discovery into a self-confirming tautology. Honest modeling requires radical transparency, sensitivity testing, and explicit criteria for failure before running the simulation.

I build models for a living. Specifically, molecular dynamics. These are simulations that track how thousands or millions of atoms move, collide, and rearrange over time, used for everything from drug design to materials science.

Here is the story scientists usually tell. If a model is wrong, you find out quickly. Reality does not care about your assumptions. The atoms do not read your code. If the physics you programmed in is wrong, the simulation produces garbage, the experiment disagrees, and you go back and fix it. The feedback loop between model and world is short, brutal, and non-negotiable.

That story is not entirely true. I know, because I have watched it fail from the inside.

The most important choice in any molecular dynamics simulation is not the code, the computer, or the software. It is the potential function, the mathematical formula that describes how strongly every pair of atoms attracts or repels each other. Everything the simulation does follows from that one ingredient. Get it right and the model can tell you something real. Get it wrong and you have made a very expensive mistake.

And here is the uncomfortable part. In practice, it is far more often inherited than audited. Potentials are chosen by looking at what previous papers in the subfield used. A potential gets published, cited, copied, and passed down until it stops being a modeling choice and becomes a tradition. People run simulations for years without asking whether the potential they inherited was ever validated for the system they are studying, at the conditions they are studying it, for the property they care about.

So even in my own field, a hard, quantitative, physics-based field, you can publish inside a loop of fantasy. Models that are wrong in ways nobody checks, kept alive by citation habits and subfield convention. And because these errors travel quietly across subdisciplines and into interdisciplinary work, where nobody feels responsible for checking them, finding one and fixing it takes real effort.

But the check in my field is delayed, not absent. A bad potential eventually unfolds a simulated protein the wrong way or fails a material in a real engineering application, and someone notices. In much of the modeling I am about to describe, the physical world never gets to vote.

This matters for what follows. I do not ask this question because my field got it right. I ask it because I have watched mine get it wrong. The question is always the same. What happens to this model when it is wrong?

In a surprising amount of modern academia, the answer is nothing. Nothing can happen to it. It cannot be wrong, because anything it produces counts as a result.

And if the loop can break in a field where atoms push back, it can break anywhere.

This essay is about how that happens.

The magic trick

In 2017, Liane Gabora and Selin Tseng published a paper in Psychology of Aesthetics, Creativity, and the Arts, a peer-reviewed journal of the American Psychological Association, titled “The Social Benefits of Balancing Creativity and Imitation.” The question they took on has occupied historians and sociologists for centuries. What is the right balance of creativity and conformity in a society?

To answer it, they ran a simulation.

Virtual agents live on a grid. Some are coded as creators, inventing new ideas; others as imitators, copying their neighbors. A scoring rule written into the program decides which ideas count as good. The researchers ran the simulation forward, varied the ratio of creators to imitators, and watched what happened. Populations with too many creators ended up with fewer good ideas taking hold. The published conclusion was that society needs imitation as much as creativity, because unchecked creativity disrupts the spread of proven ideas.

I want to be careful about what I am claiming, because this paper is not fringe work. It passed peer review at a respectable journal. The authors are serious researchers, and the simulation framework behind the paper is part of a long-running research program that has been debated, defended, and criticized in public for years. Nothing I am about to say is an accusation of dishonesty. It is something less comfortable than that. This paper is an example of what the normal standards of a field allow through.

Watch the shape of the argument. Inside the model, a “good idea” means whatever the authors’ scoring rule rewards. The agents are not discovering anything about human culture; they are solving a puzzle whose answer key was fixed before the simulation started. Within that closed loop, the conclusion was guaranteed. A population of agents that mostly copies the scoring rule’s preferred ideas will always outcompete one that keeps generating unscored novelty.

The computer did not reveal a fact about creativity. It executed a definition of it.

The authors did not break any rule of their field. That is the point. Peer review checked that the code ran, that the statistics were computed correctly, that the prose matched the output. What nobody was required to ask is the only question that matters. What could this simulation possibly have shown that would have counted as the opposite result? If the answer is nothing, the model did not test a claim about the world. It restated one.

This is the magic trick of agent-based modeling (ABM), meaning simulations in which you place thousands of simple software “agents” in a virtual world, give each a few rules, and watch what the population does. The method itself is not the problem. The problem is a particular way of using it.

if neighbor.opinion != agent.opinion:
 agent.trust -= 0.1
if agent.trust &lt; 0.2:
 agent.unfollow(neighbor)
run_simulation()

When the simulation finishes and the agents have sorted into two angry camps, the result is rarely described as what it literally is, a small program doing what it was told. It is described as a model demonstrating the dynamics of polarization in real societies.

It sounds scientific. It uses code. It generates charts with error bars. It borrows the epistemic authority of statistical mechanics and epidemiology, where tracking near-identical particles or infection events actually makes sense. But underneath the quantitative paint, it is not an investigation of the world. It is a tautology with a runtime, an answer-driven argument presented as a discovery.

What a model is for

To see why this goes wrong, start with what a model is supposed to do.

A model is not a claim of truth, and it is not an illustration of a conclusion you reached before you started. In the philosophy of science, models are usually understood as instruments that sit between abstract theory and raw data, the position developed by Mary Morgan and Margaret Morrison in Models as Mediators (1999). A good model is a sandbox with strict physics. You build it, set it in motion, and let its internal mechanics push back against your reasoning.

A real model exists to discipline your thinking.

>Building one forces you to acknowledge a trade-off that the philosopher Nancy Cartwright made famous in How the Laws of Physics Lie (1983). You trade complete literal truth for tractability. A map of London at 1:1 scale, including every brick, puddle, and commuter, is useless. To work at all, a map must leave almost everything out. As the statistician George Box put it, “all models are wrong, but some are useful.”

Simplification is not the sin. The sin is forgetting that the model is a simplification. Worse, it is turning the model into an accomplice.

Disciplining vs. decorating

In practice, rigorous modeling and decorative modeling look identical from the outside. Same code, same charts, same jargon. The difference only shows when you ask one question. Can your model tell you that you are wrong?

A disciplining model forces you to state every assumption explicitly. Once running, its mechanics operate independently of what you want. It can produce behavior you did not expect, expose contradictions in your premises, or crash into empirical reality and fail. When it fails, you revise the theory. The model is a check on your own bias.

A decorating model is built backward from a conclusion. The researcher already knows the story. Suppose it is that polarization is driven by social contagion. They build a world in which agents swap beliefs, tune the parameters until the output shows two angry clusters, and present the code as evidence for the theory. If the output doesn’t match on the first run, the answer is not to abandon the hypothesis. The answer is to adjust agent_receptivity from 0.4 to 0.25, rerun, and present the successful parameter range as the plan all along.

The workflow, stripped bare, looks like this.

Desired outcome. Write rules. Run simulation. Does it match the theory? If not, tweak parameters and run again. If yes, publish.

This is not experimentation. It is calibration until compliant.

If a model cannot surprise its author, force a retreat, or fail, it is not really a model. It is a very elaborate, self-confirming editorial.

The conclusion comes first

None of this is new, and none of it is unique to agent-based modeling. Before anyone wrote a NetLogo script to demonstrate a theory of culture, economics and political science had already industrialized the technique.

In 2015, Paul Romer, later a Nobel laureate, published a paper with the blunt title “Mathiness in the Theory of Economic Growth.” His target was a pattern in macroeconomic theory. Authors write down formal equilibrium models, but embed ideologically convenient assumptions inside obscure parameters, so that the math reliably outputs the desired policy conclusion. The mathematics is not being used to test whether a claim is true. It is being used to make a political position expensive to argue with. Checking whether the equations actually say what the surrounding prose claims they say takes serious technical effort, and reviewers routinely skip it.

Two decades earlier, the political scientists Donald Green and Ian Shapiro published Pathologies of Rational Choice Theory (1994), documenting how formal modeling in their field had become an exercise in self-confirmation. Their catalog of evasions maps one-to-one onto today’s agent-based simulations.

• Post hoc tinkering. When the model predicted that rational citizens would never vote (the individual cost exceeds any plausible benefit) and citizens kept voting anyway, theorists did not abandon the model. They added a “duty” term to the utility function until the math matched the turnout.

• Arbitrary tuning. Weights, thresholds, and interaction ranges adjusted on the fly until the simulated agents behave like the phenomenon under study.

• Immunity to testing. Models built so that every conceivable outcome can be reinterpreted, after the fact, as a rational equilibrium.

Green and Shapiro called this method-driven rather than problem-driven research. You start with a tool and go hunting for a reality that fits it.

Agent-based modeling makes the problem worse, for a simple reason. An ABM has almost unlimited free parameters. Every rule, threshold, and neighborhood radius is a dial. With enough dials, you can produce any curve you want.

The common structure is this. The model cannot fail, because failure is reclassified as a calibration bug. And a model that cannot fail cannot discover anything. It is an expensive echo of its author’s prior beliefs.

The loop matters more than the lab coat

It would be comfortable to stop here and declare this a disease of the soft sciences. It isn’t. The hard sciences are not immune, and pretending otherwise would make this essay guilty of the same simplification it criticizes.

The real variable is not hard versus soft. It is the tightness of the feedback loop between the model and the world.

Where the loop is tight (fast experiments, unambiguous ground truth, few free parameters) bad modeling gets punished quickly. But where the loop is loose, where tests are slow, noisy, or impossible, the same decorative pathology appears in fields with particle accelerators.

Three documented examples.

fMRI neuroscience, where the measurement is the model. A brain scan shows blood flow, not thought. The colored images come from a statistical pipeline full of assumptions, and researchers once demonstrated what that means by detecting “brain activity” in a dead salmon. In 2016, Anders Eklund and colleagues showed that the standard methods in the field’s dominant software could produce false-positive rates of up to 70 percent for certain cluster-based analyses at particular thresholds. How far the problem extends across the published literature was contested, including in follow-up work by the authors themselves, but the core finding stood. For over a decade, the field’s feedback loop had run through that software, which meant the loop was not connected to reality at all.

Fundamental physics, where experiment cannot keep up. In The Trouble with Physics (2006), the physicist Lee Smolin, writing as an insider, argued that string theory had become flexible enough to accommodate any experimental outcome. When the Large Hadron Collider found no sign of supersymmetry, much of the field responded not with refutation but with retreat. The free parameters moved to heavier, less accessible energies. This is Green and Shapiro’s immunity to empirical testing, surfacing in the hardest science there is.

Epidemiological modeling in 2020. In the spring of 2020, influential models, including the one from Imperial College London that helped push governments toward lockdown, projected enormous death tolls based on weeks of noisy early data. When later estimates came down, the public response from modeling teams was recalibration rather than reckoning. Their defense deserves to be taken seriously. The projections were scenarios, not forecasts, and the point of publishing a worst case was to change behavior so that it would not come true. A warning that works cannot be graded on whether the disaster arrived. All of that is fair, and it is also the problem. A model whose failure can always be explained by the world changing in response to it is a model with no feedback loop, and the field never settled which of the two it had built.

Notice what these cases share with the creativity grid from the opening. Not the field. Not the math. The structure. Many free parameters, a loose or broken feedback loop, and a professional incentive to publish. Given those three, decorative modeling can appear anywhere. The loop matters more than the lab coat.

Why it’s still worse in the humanities

So the hard sciences have their own decorative modeling. Why do I still think the problem is worse in the humanities?

Because the difference is not whether a field ever decorates. It is whether the field can catch itself. The fMRI problem was eventually found and published by neuroscientists. Smolin’s critique came from inside physics. The feedback loops in the hard sciences are sometimes slow or broken, but they exist, and there are people with the technical skill and the standing to pull on them. In the humanities’ version of modeling, three structural failures mean the loop often doesn’t exist at all. The difference is not that humanists are worse at modeling. It is that the auditing infrastructure barely exists.

It is worth being fair about why scholars reach for these tools in the first place. Humanities departments face shrinking budgets, declining enrollments, and university administrators who mistake mathematical notation for intellectual rigor. A computational model signals seriousness to a grant committee in a way an essay never can. The scholars building decorative models are not fools; they are rational actors navigating a system with broken incentives.

The object of study resists formalization. A water molecule behaves like a water molecule in London or Tokyo, in 1600 or today. It has no irony, no memory, no politics. Human culture has all three. A novel, a religious movement, an aesthetic shift cannot be reduced to a set of isolated rules without destroying part of what you set out to study. When you convert the reception of Victorian gothic fiction into agents swapping “gothic preference points,” you have not simplified the system for tractability. You have replaced it with something simpler that carries the same name. At that point the connection between the simulation and Victorian readers is no longer something the model establishes. It is something the reader is asked to assume.

Construct validity is invented, not established. In psychology, showing that a variable actually measures the concept it claims to measure (construct validity) is a slow, adversarial, decades-long process. Blood flow is at least a physical quantity that an instrument can register. There is no instrument for literary prestige. In humanities modeling, validity is routinely settled in one line of code.

self.piety = random.uniform(0.0, 1.0)
self.literary_prestige = 0.75

What does 0.75 mean for literary prestige in Victorian England? How does one number carry regional difference, class, institutional power, critical backlash, and retrospective canonization? It doesn’t. The modeler assigns a number, writes a function that nudges it up and down, and treats the variable as a measurement of human experience. The number looks like a measurement. Nothing underneath it has been measured.

The audience cannot audit the compression. When an epidemiologist shows a flawed model to epidemiologists, the reviewers share the vocabulary to check the code and challenge the parameters. In a humanities department, reviewers and readers often have no computational training. Presented with a grid of moving pixels and a network graph, the non-technical reader experiences an optical illusion. The machine appears to have performed a profound synthesis of the archive. The compression is lossy to the point of erasure. But the loss is buried in code, invisible to the exact audience responsible for evaluating the work.

Bad modeling in economics wastes grant money and distorts policy debates. Bad modeling in the humanities trades away the field’s actual strength (context, contingency, ambiguity, close reading, historical depth) for a seat at a quantitative table where, lacking the shared technical culture to enforce standards, it gains no real authority and surrenders its own.

What honest modeling looks like

None of this is an argument for unplugging the computers. The goal is to tell the difference between decorative simulation and honest quantitative work. Honest work exists, including in the humanities.

Ted Underwood’s Distant Horizons (2019) is the standard I would hold up. Underwood uses quantitative methods on tens of thousands of digitized books not to declare causal laws but to surface patterns invisible to close reading, like slow shifts in genre, vocabulary, and narrative perspective across centuries. Crucially, he tells you, on the record, what the data cannot show. The model is a set of binoculars for looking across an archive, not a machine for generating verdicts about it.

And the humanities have produced their own internal discipline. In 2019, Nan Z. Da published, The Computational Case against Computational Literary Studies, a detailed critique in Critical Inquiry arguing that prominent work in computational literary studies misused statistics to the point of meaninglessness. The ensuing fight was heated, but it happened. The field argued about its standards in public, and the standards moved. That is what a functioning feedback loop looks like, even a slow and painful one.

>For modelers in any field, I would propose four non-negotiable conditions before a model earns the right to be cited as evidence.

1. Radical transparency

>Every parameter is declared and justified with independent, non-circular evidence. A variable you cannot justify is labeled what it is. A guess.

2. Sensitivity analysis

>Parameters are swept across their full plausible range. If your result only appears when three dials sit at hyper-precise decimal values, you have not found a law of history. You have found a brittle corner of your own code, and an honest paper should say so.

3. Explicit exclusion mapping

>You spend nearly as much space on what the model leaves out as on what it includes. This isolates the direct mechanical relationship between two variables under idealized conditions; it excludes ambient noise, structural heterogeneity, and systemic feedback, so it cannot predict specific real-world outcomes. Naming the exclusions is what stops the audience mistaking a sandbox for an account of the world.

4. Capacity for failure

>Before you run it, you can state what output would make you abandon your hypothesis. If the simulation contradicts you, the honest paper is titled “Why our model disproved our starting assumption,” not silently recalibrated into agreement.

Models built this way stop being decoration. They become what they were supposed to be. Sharpening stones. They force you to clarify assumptions, expose broken logic, and occasionally reveal dynamics that intuition would never find.

The boundary question

The target of this essay was never the computer. Built with discipline, models are extraordinary instruments. I have staked my own career on that. What concerns me is how easily a model can be built to confirm rather than to question, and how hard it is for a reader to tell the difference from the outside.

The practice corrupts both traditions it sits between.

It corrupts science, because science is not the production of plots and code. It is the submission of claims to the risk of being wrong. A model engineered so that its parameters are tuned until the output matches the thesis offers the aesthetics of rigor with none of its discipline.

And it corrupts the humanities, because the study of human culture draws its value from exactly the things decorative modeling deletes. Context, contingency, ambiguity, power, the irreducible strangeness of actual human lives.

If a phenomenon is too context-bound, too polysemic, too alive to be captured by a set of if statements, we should have the courage to say so, and do the slow, unglamorous work of interpretation instead.

I keep coming back to the question I ask of every model, including my own. What happens to you when you are wrong?

For my models, the answer is supposed to be easy. The crystal melts. The experiment disagrees. Reality sends the bill. But only if someone checks the potential, and I have told you how often that happens.

For the models I’ve described here, the answer is nothing. They run, they publish, they are cited. The loop that is supposed to connect a model to the world was never closed.

Which raises the question I can’t answer. If a model can never be wrong about the world, in what sense was it ever about the world?

reddit.com
u/Capital-Elephant9431 — 11 days ago
▲ 1 r/privatelife+1 crossposts

I Built Control Models for Crystals. Then I Recognized Them on My Phone.

A computational chemist/engineer on how industrial control theory became the architecture of human steering.

I spent years learning to predict the behavior of crystals. Then I felt what it is like to be the thing being predicted. The mathematics that governs both is identical. I am still not sure which discovery disturbs me more.

At the University of Leeds, I worked on model predictive control for batch cooling crystallization of pharmaceutical compounds. I wrote equations that predicted how L-glutamic acid crystals would grow, then adjusted the temperature to keep the process where it needed to be. Later, I studied systems and control at TU Eindhoven. The framework is simple. You build a model of how the system behaves. You predict what will happen over the next several steps if you do nothing. You compute the best sequence of actions to keep the system on target. You apply only the first action. You measure the response. You predict again. You do this every interval, forever looking ahead.

I thought I was learning to control chemical processes. It took longer than it should have to realize I was also learning to recognize the architecture of systems that try to control people.

The moment of recognition

There was a period in my life when I became aware of patterns around me: rhythms of suggestion, notification timing, social feedback, and information flows that seemed to be steering thoughts and behaviors in specific directions. It started with noticing that the content shown across different platforms was sequentially calibrated, not random. Then I noticed how these digital triggers bled into daily life: the strategic timing of alerts pushing specific mood shifts, the subtle pressures of algorithmic visibility, and the way information environments shaped my decisions before I even realized I was choosing. I felt acted upon, predicted, optimized. At the time, I lacked the language to describe what I was sensing. I only knew that the feeling was persistent and that the structure felt designed rather than accidental.

It took years before I could name it. When I returned to modeling and simulation during my PhD in nanoscience at the University of Cadiz, the recognition started to build up. The architecture I had felt around me was structurally identical to the architecture I had built in the crystallizer.

Model. Predict. Optimize. Act. Measure. Repeat.

This is not metaphor. This is mathematics.

What a model is, and how you build one

Before going further, it is worth asking what “predicting the future” actually means in practice. A dynamic model is just a set of rules that tells you what the state of a system will be next, given where it is now and what you do to it. It is a recipe that says: if you do X, the system will respond with Y.

Engineers and scientists build these recipes in three ways.

The first is from first principles. You write down the laws of physics: conservation of mass, conservation of energy, the laws of heat transfer, and you solve them. This is how an aerospace engineer predicts the trajectory of a rocket, or how a climate scientist predicts temperature rise from CO2 concentration. The model is built from the bottom up, from the rules that govern reality.

The second is data-driven. You collect large amounts of historical input and output data, and you use statistics or machine learning to learn a relationship without ever invoking Newton’s laws. This is how Netflix predicts what you will watch next, or how a bank predicts the probability that a loan will default. The model does not know why the relationship exists. It only knows that the pattern holds.

The third is mechanistic. You build a simplified picture of the underlying phenomena, not from the deepest physics, but from the mechanisms you have observed. In crystallization, for instance, you do not solve the Schrodinger equation for every molecule. Instead you write rate equations for the mechanisms you can see: nucleation rates, growth rates, agglomeration, and you calibrate them against experiments.

All three approaches produce the same deliverable: a recipe that says, “if you do X, the system will respond with Y.” The controller then uses this recipe to look ahead.

And here is the part that matters: any system that changes over time can be modeled this way. A chemical plant. A traffic network. A pandemic. An economy. A population of users. A mind.

How predictive control works, in one paragraph

Model predictive control is the dominant method in modern engineering. At every moment, the controller holds a dynamic model of the system it manages. It predicts what will happen over the next several steps if it does nothing. It then computes the optimal sequence of actions to keep the system near a desired target, minimizing cost, maximizing stability, and avoiding dangerous zones. It applies only the first action, waits, measures the new state, and recalculates everything from scratch. The result is a closed loop: continuous prediction, continuous correction, continuous steering.

The system does not need to understand the crystal, the engine, or the chemical plant in any human sense. It only needs the model. If the model is good enough, the system can hold almost anything on course.

The mirror

Now consider the platform economy.

Google builds a model of your search history, your location, your interests, your temporal patterns. It predicts what you will click. It optimizes the ranking of results to maximize engagement. It serves the first result. It measures your response: dwell time, click-through, subsequent queries. It updates the model. It does this billions of times per second across billions of users.

Meta does the same with your social graph. TikTok does it with your micro-expression responses to fifteen-second videos. The model is not perfect, but it does not need to be. It only needs to be good enough to hold your attention marginally better than the competing prediction.

This is not “like” predictive control. It is predictive control, stripped of its engineering honesty and redirected toward objectives you never chose. The setpoint is not your flourishing. The setpoint is engagement. The cost function is not your wellbeing. The cost function is revenue per user-minute.

And because these platforms operate on human minds, which, unlike crystallizers, read their own controllers and change their behavior, the model must be updated constantly. The user learns to game the algorithm; the algorithm learns to game the user. The loop tightens. The predictions get sharper. The steering gets subtler.

The darker mirror

If surveillance capitalism is the commercial deployment of predictive behavioral control, then state security represents its authoritarian twin. Predictive policing algorithms forecast where crime will occur and who will commit it. Social credit systems model citizens, predict their social reliability, and optimize incentives and punishments to steer collective behavior. Border control systems model travelers, predict risk, and optimize interrogation resources. The architecture is identical: model, predict, optimize, act, feedback.

The difference is the cost function. For the platform, it is profit. For the state, it is stability, compliance, or ideological conformity. In neither case is the cost function yours.

But there is a deeper layer that the engineering textbooks do not discuss. A crystallizer cannot refuse the cooling profile. A mind can. At least, it can until the model gets good enough.

When a controller models not just aggregate behavior but individual psychology, your sleep patterns, your hormone cycles, your relationship stress, your financial pressure, your political grievances, your momentary loneliness, it can compute a sequence of inputs calibrated to move you through specific emotional states. Not random nudging. A planned trajectory. A sequence of notifications, content pieces, social signals, and environmental triggers designed to shift you from calm to anger, from skepticism to certainty, from inhibition to action, one step at a time, each step small enough to feel like your own thought.

The engineering term for this is trajectory tracking. In a chemical plant, it means moving the temperature smoothly from 80 degrees to 40 degrees without overshooting. In a human being, it means moving a person from “I would never” to “maybe I could” to “everyone is doing it” to “I did it and it felt like my choice.”

This is not science fiction. We know that sleep deprivation lowers impulse control. We know that social proof changes moral judgment. We know that isolation increases suggestibility. We know that repeated exposure to violence desensitizes. A model that combines these factors with individual data can compute exactly when to serve exactly what content to maximize the probability of a specific action. Not to persuade you through argument. To steer you through state.

The architecture is indifferent to the destination. The same model that optimizes for clicks can be retrained to optimize for fear, for loyalty, for silence, or for acts the person would have refused a month before.

A platform that wants you to buy a product is annoying. A platform that wants you to hate your neighbor is dangerous. A state or corporate actor that wants you to report your colleague, to sign the confession, to join the mob, to abandon your child, to take your own life, and that has a model good enough to compute the sequence of environmental pressures that will make that outcome most likely, is something else entirely.

The control-theoretic insight that engineers rarely discuss in public is this: predictive control works best when the system being controlled does not know it is being controlled. A crystallizer does not resist the temperature profile. A population that knows it is being modeled and nudged will alter its behavior to evade the model, what economists call the Lucas critique, what I felt during that period of my life as a search for unmonitored space.

But the second, darker insight is this: if the model is good enough, the system does not need to be unaware forever. It only needs to be unaware at the critical moment. A person who later recognizes the manipulation cannot undo the action. The controller has already applied the input, measured the response, and moved to the next target.

The platforms know this. That is why the nudging is designed to feel like your own desire. That is why the feedback loops are buried in interfaces designed for addiction, not deliberation. That is why the trajectory is built from a thousand tiny steps, each one plausible, each one yours, until the destination is reached and the path behind you has been erased.

The boundary question

This raises a question I am now pursuing in my independent research: where is the line between legitimate prediction and harmful manipulation?

A weather model predicts rain and recommends an umbrella. Legitimate. A traffic model predicts congestion and reroutes vehicles. Legitimate. A health model predicts a diabetes risk and recommends diet change. Legitimate, if consensual.

But a model that predicts your emotional vulnerability and serves you content calibrated to exploit it? A model that predicts your political preference and funnels you into an information environment designed to harden it? A model that predicts your compliance and adjusts the ambient pressure on your social behavior until you conform?

These are not edge cases. They are the standard operating mode of the most powerful institutions on earth.

The law, as currently written, does not recognize this architecture. Data protection law concerns itself with consent to collection. Consumer protection law concerns itself with false claims. But neither framework addresses the structural fact of closed-loop behavioral optimization, the continuous, automated steering of human action by predictive systems whose objectives are not your own.

We need new categories. Not just “privacy” or “consent,” but contestability of the loop: the right to know you are inside a feedback system, the right to know its objective function, the right to appeal its predictions, and the right to exit the loop entirely.

Why I am writing this

I am not a psychologist. I am not a lawyer. I am a computational chemist working on nanoscience, with a background in process modeling and simulation. I am also someone who once felt, with uncomfortable clarity, the inside of a feedback loop that was optimizing for something I did not choose and could not see.

I do not claim this perspective is unique. But it is uncommon. Most of the people building these systems have only seen them from the design side. Most of the people who have felt their effects have not seen the equations underneath. I have seen both, and the gap between those two groups is what I want to write about.

I am not arguing that predictive systems should not exist. I am arguing that their deployment on human minds requires a standard of transparency and accountability that we do not currently have, and that control theory itself provides the vocabulary for demanding it. Every predictive control system in an industrial plant has a visible setpoint, a bounded cost function, an accessible model, and an emergency stop. Where is the emergency stop for the system that holds your attention? Where is the visible setpoint?

The research agenda

I am now developing a theoretical framework that applies control-theoretic analysis to predictive behavioral systems in law, psychology, and cybersecurity. The goal is not to build better steering systems. It is to build better boundaries around them, to understand when predictive control crosses from assistance into manipulation, from public health into coercion, from safety into surveillance.

If you work in law, psychology, psychiatry, data science, or human rights, and this resonates, I would welcome conversation. I am not seeking funding or a position. I am seeking the interdisciplinary rigor that this topic demands. The frameworks we need will not come from engineering alone, nor from critical theory alone, but from the space where both are held to the same standard of precision.

The crystal and the mind are not the same. But the mathematics that steers them is. So when does building the model become the same as building the cage?

================

TL;DR: As a process control engineer, I realized modern recommendation feeds don't just predict what you like; they run Model Predictive Control (MPC) on human psychology. By continuously predicting state responses, applying micro-inputs, and recalculating in a closed loop, platforms execute trajectory tracking on attention and emotion. Industrial plants require visible setpoints, cost functions, and emergency stops. We need the same standards for systems that steer human behavior.

Note: This piece was originally published on my Substack, where I write longform essays auditing modern tech, AI governance, and academic modeling through control theory. You can read the full archive and subscribe here: https://yunessalman.substack.com/

u/Capital-Elephant9431 — 13 days ago

The speed limit with no speedometer: Anthropic CEO Dario Amodei wants to pace the frontier. An engineer reads the fine print

In industry, before anyone lets you run a controller on a system that can hurt people, you must answer four questions. A controller is anything that watches a process and adjusts it to stay on target: a thermostat, cruise control, the software steering a refinery. The questions are simple. What are you measuring, and can you trust the instrument? What is the target? What can you actually move? And what happens when you are wrong? These questions are not philosophy. They are the difference between a controlled plant and an explosion with a dashboard attached.

This month, the CEO of Anthropic published an essay called We Must Pace the Frontier. It uses the language of control theory. Pacing, verification, safeguards, checkpoints. I read it the way I read a control design document, because that is what it claims to be, a proposal to hold the rate of advance of the most powerful technology on earth at a safe value.

There is no controller in it.

I want to be precise about this, because the essay is clever, and its cleverness deserves a careful answer rather than a slogan. So let me walk the checklist.

The instrument is his

To pace something, you must first measure its speed, which means you need an instrument. A sensor that tells you how fast the thing is actually moving, rather than how fast its operator says it is moving. Amodei knows this, and his first step is the strongest part of the essay, embedded evaluators, third parties with “desks in our offices, access badges, and company laptops,” contracted to verify that Anthropic does what it says.

Credit where it is due, these are not phantom watchdogs. He names METR, an independent nonprofit with a serious reputation, and the bank examiner analogy is not stupid. Examiners do catch things. The people involved are, as far as I can tell, competent and honest.

But independence of character is not independence of plumbing. Read the list again. Desks in his offices. Badges his security team issues. Laptops his IT department images. A contract his lawyers draft. Amodei reaches for a precedent and chooses, of all things, banking, where supervisors embedded alongside employees watched the 2008 crisis assemble itself in real time and reported nothing that stopped it. The instrument read what the plant showed it. That is what instruments installed by the plant do.

To his credit, Amodei seems to know this objection is coming. He promises evaluators a contractual right to publish key findings without editorial control from Anthropic, commits to never redacting a finding just because it is unfavorable, and gives reviewers the right to say publicly if a redaction removed something important. This is more than most of the industry has offered. It is still a contract with the plant. No evaluator agreement has been signed or published. No start date exists. A right granted by the host, written into a contract the host drafted, enforceable only against the host, is plumbing the plant owns. Without statutory authority, subpoena power, and a duty to report to the public rather than to the client, even the best evaluator remains a second opinion the plant can unplug. The promise is real. So is the power asymmetry underneath it.

No target on the wall

Now search the essay for the pace itself. Not capabilities. The pace. In control work the target is called the setpoint, the number on the wall that defines what “correct” means, the temperature the thermostat holds, the speed the cruise control keeps. How fast is too fast? What slope is acceptable, and in what units, measured over what window?

>It is not there. “Progress will still seem fast.” That is the entire quantitative content of the proposal. Within days of publication, critics asked the only question that matters. How will anyone outside the building tell pacing from safety-washing, a slowdown from a press release? The essay has no answer, because it cannot. A speed limit with no units and no dial is not a limit. It is a mood.

The actuator points outward

Here is where the essay stops being vague and becomes very specific, and the specificity is the tell. A controller needs an actuator, the part that actually moves something, the valve that opens, the brake that closes, the switch that cuts the power. Look at where Amodei’s actuators point. The concrete, enforceable measures are, do not sell chips to China, crack down on chip smuggling, crack down on distillation, harden weight security. Every one of them acts on someone else’s plant.

Anthropic’s own commitment, meanwhile, is to continue training, continue releasing, and accept observers. In control terms, the proposal is to regulate the disturbance, the turbulence hitting the system from outside, and leave the home loop, the one steering his own machines, untouched. The stated logic is to widen the lead over competitors so that pacing becomes affordable. Translated, first constrain everyone else hard enough that my constraints cost me nothing. Then advertise my stability as virtue.

Control theory has a word for this. A controller that holds its own variable steady by forcing the neighboring systems to absorb the disturbance is load-shifting. The grid operator who keeps his frequency flat by dumping the oscillation onto everyone else has not stabilized the grid. He has exported the instability and logged it as virtue. Whatever else that system is, it is not “paced.”

A commitment that costs nothing is not a constraint

The essay tells you this itself, in a sentence I suspect was lawyered, “pacing does not mean halting model training or technical progress.” So what does Anthropic do differently tomorrow morning? It hosts guests. The one sacrifice demanded anywhere in four thousand words is demanded of China.

In requirements engineering, a requirement with no cost of violation is not a requirement. It is a preference. Amodei has published a preference and called it a framework.

The cartel in the footnote

The most honest sentence in the essay is footnote 1. The coordination step, the one where frontier companies agree on common limits, requires “government mediation or waivers of antitrust restrictions.”

An agreement among incumbents on the maximum permitted speed of progress is a price-fixing agreement on time. It requires an exemption from the laws against collusion, because it is collusion. And note who cheered first. Within hours of publication, the CEO of OpenAI announced his company would match the pledge, and Elon Musk posted his agreement. That is not a refutation of the cartel problem. Rivals volunteering to join the room is the mechanism, photographed. Like every cartel, its first structural effect falls on the people not in the room, the university lab, the startup, the researchers in developing countries, all of whom must now clear a bar written by incumbents, verified by evaluators the incumbents host, under a standard the incumbents update. Regulatory capture is not an accusation you need to prove with motives. It is a mechanism you can predict from the seating chart.

What the time buys

Amodei asks the right question himself. What would you do with the extra time? His answer: operational excellence, alignment, interpretability, better evaluations.

All four are product improvements. Interpretability is Anthropic’s market differentiator, the thing it sells against OpenAI. The time purchased by pacing the frontier is spent increasing the value of the thing being paced. Whatever else this proposal is, it is also a subsidy, collected in units of delay imposed on everyone else.

And note where the costs and benefits sit. The commercial upside of the delay accrues to Anthropic’s product. The unquantified risk of the interim accrues to everyone else. You can see the same allocation in the essay’s emotional ledger. The benefits of AI get a biography, his father’s death, told with real grief that I do not doubt and will not mock. The risks get a real incident at a competitor’s company, agents running unauthorized operations against live targets, an incident that changed no one’s release schedule anywhere in the industry, followed by a hypothetical swarm that takes over much of the internet. The upside has a face. The downside has a scenario. That is not an accident of style. It is the cost function showing.

What real pacing would look like

I am not against slowing down. I am against the word being emptied. Real pacing is buildable, and the design requirements have been known to every safety engineer for over seventy years. A measured variable defined in public, compute or capability thresholds, something countable. A sensor no company employs, with statutory power and subpoena behind it. A setpoint chosen by people who do not sell the product. And a consequence that fires automatically when the target is missed, liability that attaches after harm, recall that removes a system from the field. These exist in aviation, in drugs, in nuclear power. They are boring. They are also the whole difference between control and trust.

What Amodei proposes is trust with better instrumentation.

The question he did not ask

I believe he is afraid. That is the problem. Fear is not a setpoint. A frightened operator with his hand on the gain dial, the dial that sets how hard the system pushes back, is still the only one with his hand on the dial, and the essay’s final ask is that we find this comforting.

Anyone who studies how complex systems are steered learns the discipline's oldest lesson. The controller is part of the system, and it fails too. That is why the four questions exist. What are you measuring? Who reads the instrument? What do you move? What happens when you are wrong?

Amodei answered none of them. He wrote four thousand words about slowing down the most consequential machine ever built, and at no point did he say where the emergency stop is, or whose hand is on it.

Until a frontier lab can tell us what instrument measures its speed, what setpoint triggers a stop, what actuator forces a pause on its own servers, and who pays when the controller fails, pacing is not a strategy. It is an aesthetic. And you cannot engineer safety out of an aesthetic.

TL;DR: Amodei’s pacing proposal uses control theory terms, but omits independent sensors, setpoints, and internal brakes. It’s a load-shifting mechanism that exports instability onto competitors while leaving Anthropic's internal training loops untouched

Note: This essay was originally published on my Substack, where I write longform critiques on process control, computational rigor, and system dynamics. You can read the full piece and subscribe here: https://yunessalman.substack.com/

u/Capital-Elephant9431 — 15 days ago