Textual Tells

Week 3

Every reliable tell has a half-life.

Tells that already decayed

  • an odd fondness for “delve” — spiked hard in scientific abstracts right after ChatGPT launched, then got trained away once everyone noticed
  • paragraphs arriving in tidy threes
  • a habit of closing with “in conclusion”

None of these survive contact with a model released six months later.

What’s held up longer

  • perplexity — how “surprised” a language model is by its own next word
  • burstiness — human writing swings between simple and complex; generated text tends to flatten toward a single register
  • hedging patterns that repeat across a whole document rather than varying naturally

ChatGPT is a bullshit generator.

— Arvind Narayanan, Princeton, 2023

Why “bullshit,” precisely

Narayanan meant it as a diagnosis, not an insult, borrowing directly from Harry Frankfurt’s distinction: a liar cares what’s true and hides it; a bullshitter — and a next-token predictor — doesn’t track truth at all.

The false-positive problem

A distinctive, idiosyncratic human voice can look “generated” to a naive detector, because both are unusual relative to average prose. This isn’t a footnote — it’s the entire subject of week 11.

Further reading

AI Snake Oil (Narayanan & Kapoor) — further reading