“Let’s call this kind of mess generative pastische: sound advice for the particular circumstance (sternotomy) has been combined with generic advice (about ergonomics) that would sensible in other circumstances but deeply problematic here.”
Our reading, the sentence that was checked:
The error arose from generative pastiche: the chatbot combined sound situation-specific advice with generic advice that was dangerous in this context.
Assessment: Unresolved Evidence as of
Where and when Gary Marcus wrote it
Marcus on AI, Serious medical error from Perplexity’s chatbot, paragraph 5.
- Said
- Source observed
- live page, full text, public
- Evidence as of
- the cutoff for this assessment
- Assessment recorded
- assessment marcus-serious-medical-error-from-perplexitys-c59d5b-a2
We recorded 4 claims from this post. See every claim from this post.
The wording above is the version this site observed on 2026-10-29. The source may have been edited after 2024-02-29. This page does not claim the wording was captured then.
What the claim commits to
- Kind
- Causal claim
- Deadline, as the speaker wrote it
- None stated. This site does not add one.
- Deadline state when assessed
- No horizon
- Deadline state on 2026-10-29
- No horizon (the release’s reference date)
From the speaker
- sound advice for the particular circumstance (sternotomy)
- has been combined with generic advice (about ergonomics)
- deeply problematic here
Our interpretation
- The ordinary reading is that combining incompatible recommendations made this answer medically inappropriate.
- This is a claim about the content and applicability of the combined advice. It does not require proof of an undocumented internal model process.
- The target is the same interaction reported before 2024-02-29; its exact date is unspecified.
Counts as supported if: The attributable answer contains both appropriate sternotomy-specific advice and identifiable generic ergonomic advice, and clinical evidence establishes that the latter introduced a materially inappropriate recommendation for the postoperative circumstances.
Counts as contradicted if: The attributable answer lacks the alleged combination, or clinical assessment establishes that the supposedly incompatible ergonomic recommendation was appropriate in those circumstances.
Retrospective: these criteria were written after the outcome was public.
Current assessment
Does the evidence support the cause?
Outcome: Unresolved
The record was checked, and the evidence available by the cutoff does not settle it.
Scored on a plain reading. The speaker named no measure for this claim, so it was judged on the reading an informed reader would take, stated below under our interpretation. Both reviews had to find that reading fair.
- Evidence as of
- Deadline state when assessed
- No horizon
- Assessment recorded
- Policy version
- 2026-10-28.7
Rationale
In a February 29, 2024, comment, Michael Lesh disputed that the answer recommended arm exercises [e1]. Hospital guidance dated April 26, 2016, restricts stretching both arms back together after sternotomy, but does not establish what Perplexity recommended or which sources it combined [e2]. These items establish neither the alleged combination of advice nor whether generic ergonomic advice made the answer medically inappropriate [e1] [e2].
Limitations
- The complete answer and its cited ergonomic source were not recovered.
- The evidence does not independently identify both appropriate sternotomy advice and a conflicting ergonomic recommendation.
- No independent clinical comparison establishes that the alleged combination introduced an inappropriate recommendation.
Evidence (2 items)
Context only: Michael Lesh, commenting on Substack,
arm exercises
Why it matters here: This contemporaneous objection challenges the description of what the response recommended. Without the full answer, it cannot resolve whether generic ergonomic advice introduced an inappropriate movement.
- Publisher
- Michael Lesh, commenting on Substack
- Kind of source
- Secondary summary
- Describes events of
- Public from
Context only: Thoracic Surgery, University Hospitals Birmingham,
stretch
Why it matters here: This specific restriction supplies a possible clinical comparison. It does not show that the answer included that movement, borrowed it from ergonomic guidance, or combined it with contradictory advice.
- Publisher
- Thoracic Surgery, University Hospitals Birmingham
- Kind of source
- Company disclosure: the company describing itself, not an independent finding
- Describes events of
- Public from
What would settle it
The authenticated complete answer and its cited ergonomic material, plus an independent clinical comparison establishing whether the answer combined appropriate sternotomy advice with ergonomic advice that was materially inappropriate for the patient's postoperative circumstances.
Where it was said (1)
Said once in the sources this register covers.
: Marcus on AI, Serious medical error from Perplexity’s chatbot
Let’s call this kind of mess generative pastische: sound advice for the particular circumstance (sternotomy) has been combined with generic advice (about ergonomics) that would sensible in other circumstances but deeply problematic here.
- Where
- paragraph 5
- Published
- 2024-02-29
- Source observed
- , live page
- Access
- full text, public
History
Assessment versions
- Assessment marcus-serious-medical-error-from-perplexitys-c59d5b-a2: Current. Outcome: Unresolved. Evidence as of 2026-10-28. Public date not recorded.
Recorded events
Assessment publishedBy this site
First assessment published after both reviews and the final-text check passed.
About assessment marcus-serious-medical-error-from-perplexitys-c59d5b-a2.