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Main positions:Director, High Performance Computing Platform, PKU
Degree:Doctoral degree
Status:Employed
School/Department:Institute of Theoretical Physics

Lei Yian

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Education Level: Postgraduate (Doctoral)

Administrative Position: Associate Professor

Alma Mater: Peking University

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Randomness: Between Realism and Statistical Methodology
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Randomness: Between Realism and Statistical Methodology

I. The Starting Point: The Tension Between Realism and “Intrinsic Randomness”

From a classical realist perspective, we assume that every natural process has definite causes and a determinate evolutionary path:
even if we do not yet know all the details, those details objectively exist.

In contrast, the notion of “intrinsic randomness” asserts that:
certain events have no deterministic mechanism at the ontological level—only probability distributions exist. At this level, the universe “is fundamentally rolling dice.”

This sets up a fundamental contradiction:

  • Realism demands: Natural processes are ontologically determinate and complete (even if our knowledge is limited).

  • Intrinsic randomness claims: Some processes are ontologically indeterminate and uncaused.

Logically, “lack of information” and “intrinsic randomness” are entirely distinct statements.
Yet in practice, they are constantly conflated—and often quietly equated—in statistical methodology.

To clarify this issue, we must first examine the proper role of statistical methods.

II. The True Role of Statistical Methods: “Secondary Randomness” Within an Assumed Theory

1. Nearly All Experimental Analyses Rely on Stochastic Models

Whether it’s counting statistics in physics, survival analysis in biology, time-series modeling in economics, or questionnaire data in psychology,
almost every empirical discipline builds its analysis on a common methodological pattern:

  • Assume a stable probability distribution (e.g., Gaussian, Poisson, exponential, etc.);

  • Treat individual experimental outcomes as random samples drawn from that distribution;

  • Use tools like maximum likelihood estimation, Bayesian inference, or confidence intervals to estimate parameters and test hypotheses.

This approach is operationally powerful—but philosophically rests on a crucial assumption:

The so-called “random fluctuations” are meaningful only under the presumption that a more fundamental theory is already approximately valid.

Examples:

  • In radioactive decay experiments, we assume each nucleus has a constant decay probability λ;

  • In electron-counting experiments, we model counts as a Poisson process;

  • In Gaussian noise models, we assume countless microscopic perturbations can be “averaged out” via the Central Limit Theorem.

In other words, the randomness in statistical models is a secondary description, built atop a macroscopically stable structure.
At this level, randomness functions as a pragmatic working assumption—not an ontological declaration.

2. “Effective Intrinsic Randomness”: A Provisional Endpoint Within a Given Framework

In practice, statistical methods often treat measurement errors and fluctuations as “intrinsically random”—but only within a bounded context:

  • We acknowledge that, given current theory and experimental precision, these fluctuations cannot be further decomposed or explained;

  • So we label them “essentially random noise” and construct a “final” probability distribution;

  • All unexplained deviations are then absorbed into the tails of this distribution.

This practice has two sides:

  • On one hand, it enables standardized, operationalizable experimental analysis—the backbone of scientific practice;

  • On the other, it subtly conflates a methodological endpoint with an ontological conclusion, blurring the line between “we don’t know enough” and “nature itself has no cause.”

More subtly: even as methods improve and precision increases, we continue using the same “intrinsically random” distribution beyond the new resolution limit.
This implies:

Within statistical methodology, “intrinsic randomness” serves as a procedural stopping point, not a claim about physical ontology.

III. The Logical Status of “Intrinsic Randomness”: Neither Verifiable Nor Falsifiable

1. Why “Intrinsic Randomness” Cannot Be Verified

To prove that a phenomenon is intrinsically random would require showing that:

No possible deeper theory could ever provide a more detailed deterministic account of it.

This would entail:

  • Exhausting all conceivable theoretical frameworks;

  • Demonstrating that no hidden variables, deeper structures, or topological mechanisms could ever exist.

This is logically impossible.
Thus, “intrinsic randomness” is unverifiable in principle.
At best, we can say:

“Given current theory and experimental precision, it appears random.”
But we can never conclude:
“It must be random at the ontological level.”

2. Why “Intrinsic Randomness” Is Also Hard to Falsify

Conversely, one might try to disprove intrinsic randomness by uncovering deterministic patterns beneath apparent randomness—for example:

  • Discovering periodicities, chaotic attractors, or hidden variables behind processes once deemed random;

  • Using higher-precision instruments to resolve what was previously labeled “noise.”

Such advances can indeed weaken claims of intrinsic randomness in specific domains.
But the general assertion—“There exists some ultimate intrinsic randomness somewhere in nature”—cannot be definitively falsified through finite empirical investigation.
Just as we can never exhaust all scales and scenarios to prove “no deeper cause exists anywhere,” we cannot rule out the possibility of hidden order everywhere.

Therefore, from a strict philosophy-of-science standpoint:

“Intrinsic randomness” is closer to a metaphysical stance than an empirically decidable scientific proposition.

IV. Lack of Information ≠ Intrinsic Randomness: Distinguishing Epistemology from Ontology

1. Epistemic “Randomness”: A Statistical Encoding of Incomplete Knowledge

In actual scientific work, we replace “unknown parts” with “random variables” as a technique of information encoding:

  • Unable to track every air molecule, we use temperature, pressure, and Brownian motion in thermodynamics;

  • Unable to monitor each electron’s microscopic environment, we model detector responses as “Gaussian noise.”

In such cases, “randomness” means:

  • We lack sufficient information about the system’s microstate;

  • At the macro scale, we represent this ignorance via probability distributions over indistinguishable microstates.

Thus, this kind of randomness is fundamentally:

An expression of epistemic limitation—a feature of our knowledge, not of nature’s ontology.

2. Ontological “Randomness”: A Direct Challenge to Realism

In contrast, strong ontological randomness asserts:

“Certain natural events have no sufficient cause at the deepest level—only a primitive probabilistic mechanism governs them.”

This amounts to claiming that:

  • Even with infinite experimental precision and a complete theoretical framework,

  • We could never predict individual outcomes deterministically—only assign probabilities.

This directly contradicts traditional realism:

  • Realism: Natural processes have objective structures and causal chains; our limitations are epistemic.

  • Intrinsic randomness: At some level, nature is “causeless but effectful”—a field of probabilistic happenings.

Thus, elevating “randomness” from an epistemic tool to an ontological property amounts to:

Voluntarily abandoning the search for deeper causes;
Sanctifying the endpoint of statistical methodology as the endpoint of physical reality.

V. The Implicit Philosophy of Statistical Methods: Between Technical Success and Ontological Caution

1. Why Statistical Methods Work So Well

The power of statistics lies in its ability to:

  • Extract robust regularities from limited data using minimal structural assumptions (e.g., i.i.d., stationarity);

  • Deliver reliable prediction intervals and risk assessments even without detailed mechanistic models.

This success stems from:

  • The frequent presence of macroscopic stability and scale separation in real systems (microscopic details average out);

  • Theorems like the Central Limit Theorem, which ensure predictable high-level behavior under weak dependence.

Crucially, however, this works only under a key condition:

Statistical methods do not require—or assume—that nature is truly random.
They only ask: “Does a random model stably describe the data at the current scale and precision?”

In short: statistics is a tool, not a metaphysical commitment to “the universe is dice.”

2. Continuous Refinement Leaves a “Random Residue”

As theory and technology advance, we can:

  • Improve instrument resolution, narrowing error bars;

  • Introduce richer models (mixture models, hierarchical Bayes, memory-inclusive processes) to explain what was once called “noise”;

  • Recover hidden structures previously buried in statistical tails.

Yet, even after such progress, a new residual component remains unexplained—and is again labeled “intrinsically random.”

This creates a recurring pattern:

As understanding deepens, the domain of “intrinsic randomness” shrinks—but a residual tail is always retained as a “catch-all.”

From a realist viewpoint, this persistent residue simply indicates:

Our current knowledge is still incomplete—
Not that nature has finally “become pure dice” at some scale.

VI. Conclusion: Why “Intrinsic Randomness” Is Fundamentally Incompatible with Realism

Synthesizing the above, we can state clearly:

Statistical methods rely on randomness as a foundational tool across all sciences—but this randomness is typically:

  • Secondary: valid only within a given theoretical and precision framework;

  • Epistemic: an efficient encoding of information gaps and microscopic complexity;

  • Methodological: a practical assumption, not an ontological claim.

Lack of information ≠ intrinsic randomness:

  • The former concerns the limits of what we can know and measure;

  • The latter makes a bold assertion about nature being “causeless at its core.”

Equating the two is a conceptual slide and a philosophical overreach.

Moreover, “intrinsic randomness” is neither verifiable nor falsifiable:

  • Proving it would require ruling out all possible deeper theories—impossible;

  • Disproving it would require complete knowledge of all processes at all scales—equally impossible.

Thus, it functions more as a metaphysical choice than a scientific hypothesis.

From a realist standpoint, intrinsic randomness and realism are ontologically incompatible:

  • Realism holds that natural processes possess objective causal structures, however hidden;

  • Intrinsic randomness denies such structures at some level, replacing causality with primitive probability.

Accepting the latter means abandoning realism at that level.

Therefore, the more prudent and scientifically sound stance is:

  • In practice: Continue using statistical methods fully, treating “randomness” as a powerful cognitive and technical tool;

  • In ontology: Remain cautious—refuse to hastily elevate “statistical irreducibility” to “ontological acausality”;

  • Interpret every “random tail” not as evidence of cosmic dice-rolling, but as a reminder of our incomplete understanding.

This position honors the technical power of statistics while preserving space for deeper inquiry—preventing science from slipping into the nihilism of “essential randomness” and keeping the door open for more profound theoretical discoveries.