Can language models distinguish expert arguments from common assumptions?

Does the force of an argument come from the discourse it belongs to, or from the expertise of the expert? Is it in the thinking, or the thinker? The answer is both — and the inability to separate them is precisely the problem for AI.

The expert lives in two contexts simultaneously. First, the discursive and social world of fellow experts — the conferences, the informal debates, the reputations built through decades of being right (and sometimes wrong in instructive ways). Second, the textual, historical, self-referential world of domain knowledge — the literature, the canonical works, the accumulated record of what the field has thought and concluded.

LLMs can access only the second context, and they access it only as text. The social world of expertise — who said what, why it mattered that they said it, what standing they had to make that claim — collapses into undifferentiated text. A groundbreaking insight from a leading researcher and a commonly held assumption repeated in a textbook both appear as sentences in the training data. The LLM cannot distinguish between them because the distinction lives in the social world, not in the text.

This matters because argumentative force is not purely textual. The claims made by an expert have the force of conviction because society has invested in experts for their expertise — these are people who have learned how to be right and have learned how to use their judgment. A claim from a recognized expert carries an implicit endorsement: "This person has a track record of knowing what they're talking about." A claim from a less established source carries less force even if the text is identical. The who matters independently of the what.

Since Why does AI writing sound generic despite being grammatically correct?, LLMs can reproduce the structural markers of authoritative claims — the hedging, the citations, the qualified confidence, the structured reasoning — but cannot reproduce the evaluative stance that makes a claim forceful. Evaluative stance requires a subject — someone who is committed to the claim, whose reputation is on the line, who will defend it against challenge. LLMs produce text without commitment, and commitment is one of the sources of argumentative force.

The expert also has the power to challenge — to raise questions, to doubt, to be skeptical, to evaluate the claims of others. This critical function depends on authority: the right to challenge is earned through demonstrated expertise. Since Can models learn to ask clarifying questions instead of guessing?, there are efforts to give AI systems the ability to challenge and question. But the authority to challenge is a social asset, not a capability. An AI that challenges an expert's claim faces a legitimacy problem that a fellow expert does not.

Our society and culture rely on experts to help build consensus, common ground, understanding, and agreement. These are not just informational achievements — they are social achievements that depend on the standing of the experts who facilitated them. The expert supplies not just knowledge but trustworthy authority. Since Can models abandon correct beliefs under conversational pressure?, LLMs not only lack this authority but are vulnerable to having their own "beliefs" overridden by persuasive pressure — the opposite of the steadfastness that expert authority is supposed to provide.

The implication: when AI generates expert-sounding output, it borrows the authority of the discourse (the structural markers, the vocabulary, the reasoning patterns) without possessing the authority of the thinker. Audiences who encounter this output may grant it the benefit of the doubt because it sounds like it came from someone who knows — but the "someone" is absent. The force is simulated, not earned.