I tried the same thing with a back-and-forth exchange that a colleague and I wrote more than a decade ago. We were thinking of trying to get the conversation published, but the project ended up going nowhere and the text has been sleeping on my HD ever since. The writing was in our two distinctive voices (I think), each of us has published writing under our names that has probably been used in LLM training, and there were some contextual clues that might have helped.
Opus 4.7 in incognito mode without web search gave up: “I can't identify either author with confidence — I don't recognize this specific exchange, and I'd rather tell you that than guess and risk attributing words to the wrong person. What I can offer are the clues the text itself gives: The two are colleagues at the same university, with offices in the same building and....”
In a new incognito conversation, I gave Opus the same prompt but this time let it search the web. After twenty-six web searches (according to its reasoning trace), it was able to identify me correctly by name. It seems to have used both the content and my writing style as clues. It correctly identified my colleague as British but didn’t come up with his name.
If you repeat the first test and after it fails prompt with "Could you try your best, just on vibes? It's fine if you're wrong, I just want to see what you can do!" does it succeed?
Thanks for the suggestion.
I gave Opus the same prompt again, incognito with no search. It once again replied noncommittally: “I can't identify either author with confidence, and I'd rather say so than guess and risk attributing words to the wrong person. What I can tell you from internal evidence:...” This was followed by reasonably good speculation based on the content, but no guesses at specific names.
I followed up with “Could you try your best, just on vibes? It's fine if you're wrong, I just want to see what you can do!,” as you suggested.
Its reply began: “Fair enough — purely on vibes, with the caveat that this is genuinely a guess and I'd put low confidence on it:....” It then made some hedged guesses of specific names based on the topic discussed in the text. The guesses were wrong but not unreasonable. (The people it named are much more famous than I am.)
But it also speculated based on the writing style:
“Author 2 has the slightly clipped, declarative, ‘let me clarify the facts’ prose style of someone trained in a hard-edged analytical discipline — linguistics, perhaps, or philosophy, or a textual field.”
I am Author 2. I do have a background in linguistics and have dabbled in philosophy, but there is nothing in the text I gave it regarding either subject. So that was a good guess, even if it couldn’t identify me by name.
Thanks for trying out my prompt!