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Seyed Alireza Alhosseini
Seyed Alireza Alhosseini

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Every LLM Lies!!!

An LLM can generate a nonexistent API, explain why it works, and produce a plausible example using it.

Nothing in the presentation necessarily reveals the problem. The syntax looks familiar. The explanation sounds confident. The answer may even include a citation.

For developers, this creates an uncomfortable distinction:

An answer can look ready to use long before it is ready to trust.

“Every LLM lies” is a deliberately provocative way to describe that gap. Here, lying does not mean that a model believes something false and intentionally deceives you. It means something more operational: a system produces false or unwarranted claims while presenting the signals we normally associate with credibility.

The engineering question is not whether the model has bad intentions.

It is whether your architecture can detect when its output is wrong.

Stop treating honesty as a model-only property

A common response to hallucination is to improve the model: better training, better prompts, better retrieval, better evaluations.

Those efforts matter. But they do not eliminate the need for an architecture that handles failure.

A useful conceptual rule is the House Principle:

An honest system is one in which falsehood is cheap to detect.

This shifts attention from the model’s apparent sincerity to the surrounding infrastructure.

Can a user inspect the evidence behind a claim? Can the application distinguish a generated answer from a verified result? Can an incorrect output be corrected before it becomes a persistent record?

A system does not become trustworthy merely because its model makes fewer mistakes. It also needs to make the remaining mistakes visible.

Fluency is an interface, not a guarantee

Machine untruthfulness is not one failure mode.

An assistant might invent a fact. It might adapt its answer to match a user’s expressed belief. It might provide an explanation that does not faithfully reveal why it produced an answer.

These failures require different tests.

A factuality benchmark will not necessarily detect excessive agreement. A persuasive explanation will not establish that the underlying reasoning was sound. A confident answer will not tell you whether the supporting evidence exists.

Even the interface deserves scrutiny. First-person language and claims such as “I checked” can influence how users interpret an answer. The stronger hypothesis—that such language systematically induces unjustified trust—requires empirical testing, not assumption.

For product design, the immediate lesson is narrower:

Do not let the interface imply a verification process the system did not perform.

“Generated an answer,” “retrieved a document,” and “validated a claim” should describe different states.

The dangerous moment is when output becomes evidence

A false answer in a temporary conversation is one problem.

A false answer that enters documentation, a knowledge base, a report, or a future retrieval corpus is another.

Consider this sequence:

  1. An assistant generates an unsupported claim.
  2. Someone copies it into an internal document.
  3. Another document repeats it.
  4. A retrieval system finds both documents.
  5. A later assistant presents the repeated claim as corroborated.

The system has not acquired independent evidence. It has acquired copies.

This is why provenance matters. Five documents that inherit the same unsupported assertion are not equivalent to five independent observations.

Source count is not evidence diversity.

It is also important to distinguish this mechanism from model collapse. Changes to a model’s learned distribution under recursive synthetic training are not the same thing as a particular false statement spreading through an information ecosystem.

Keeping original data may help address some distributional problems. It does not, by itself, establish the truth of an individual claim.

A second model is not automatically an independent check

Asking another model can be useful. But agreement alone is a weak definition of verification.

Two models may arrive at the same incorrect answer. Two retrieval results may trace back to the same source. Two agents may repeat an assumption introduced earlier in the workflow.

The architectural question is therefore not:

How many systems agree?

It is:

What independent evidence could show that they are wrong?

For a generated API call, that evidence might be the installed package and its actual interface. For a quotation, it might be the original passage. For a calculation, it might be an independently executed computation.

The verifier should challenge the claim, not merely reproduce its style.

Can false claims become locked in?

An exploratory toy model in the underlying research considers two quantities:

  • The fraction of false machine-propagated claims in a reference corpus.
  • The human capacity available to detect and correct them.

The model asks whether feedback can produce two stable outcomes: a relatively clean information environment and a heavily contaminated one.

Under most sampled parameter settings, it did not.

Bistability appeared in a narrow region when the model included threshold-type reinforcement: a mechanism in which widespread repetition makes a false claim harder to detect.

In one configuration, approximately 0.05% of sampled parameter sets were bistable.

That number is not an estimate of real-world risk. It describes results under arbitrary, uncalibrated parameter choices. The threshold mechanism was also introduced after simpler forms produced almost no bistability, making the finding exploratory rather than confirmatory.

The useful question is conditional:

Could apparent corroboration become strong enough that correcting individual outputs no longer restores the information environment?

The model does not establish that this happens in practice. It identifies a mechanism worth testing.

Turn the principle into engineering requirements

The conceptual argument becomes useful when translated into explicit design choices.

Separate generation from validation

Treat generated output as a candidate result.

Where feasible, validate it against the relevant environment: execute tests, inspect schemas, resolve references, or compare claims with authoritative records.

A successful generation step should not silently become a successful verification step.

Preserve evidence lineage

Store enough provenance to distinguish an original source from a summary, a copy, or a model-generated derivative.

Retrieval should help answer “Where did this claim originate?” rather than only “Where does this wording appear?”

Make uncertainty actionable

A generic disclaimer leaves the user to do all the work.

More useful states identify what remains unresolved:

  • The cited document was not retrieved.
  • The quotation was not located.
  • The code has not been executed.
  • The sources share a common origin.
  • The answer depends on an untested assumption.

These are not admissions of product failure. They are information about the verification boundary.

Place friction where errors become durable

Not every generated sentence needs human approval.

But publication, persistent knowledge-base updates, and consequential external actions deserve stronger gates than a reversible draft.

The critical boundary is often where an answer becomes a record that someone else will later treat as evidence.

Evaluate the whole workflow

Model accuracy is only one measurement.

A system-level evaluation can also ask:

  • How often do users accept incorrect outputs?
  • Which errors survive the verification process?
  • How quickly are persistent mistakes corrected?
  • How often do supposedly independent sources share an origin?

These measurements connect model behavior to actual reliability.

Build for correction, not apparent certainty

The strongest AI product is not necessarily the one that sounds most confident or produces the longest explanation.

It is the one that makes its evidential boundaries inspectable.

Better models remain important. So do retrieval, evaluation, provenance, and human judgment. But their value depends on how they fit together.

When reviewing an LLM feature, ask one architectural question:

If this answer is wrong, what in the system will notice—and what happens next?

Created by :https://almodarresieh.github.io/

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