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GPT-5: "How many times does the letter b appear in blueberry?"

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Re: GPT-5: "How many times does the letter b appear in blueberry?"

#171

Post by furyofantares »

spwa4 wrote: post #32
andrewmcwatters wrote: post #26

Earlier quoted context omitted.

No, it's the entire architecture of the model. There's no real reasoning. It seems that reasoning is just a feedback loop on top of existing autocompletion. It's really disingenuous for the industry to call warming tokens for output, "reasoning," as if some autocomplete before more autocomplete is all we needed to solve the issue of consciousness. Edit: Letter frequency apparently has just become another scripted out…

I had a fun experience recently. I asked one of my daughters how many r's there are in strawberry. Her answer? Two ... Of course then you ask her to write it and of course things get fixed. But strange.

To be honest, if a kid asked me how many r's in strawberry, I would assume they were asking how many r's at the end and say 2.

Re: GPT-5: "How many times does the letter b appear in blueberry?"

#172

Post by Chinjut »

mikehearn wrote: post #132

This is a well known blindspot for LLMs. It's the machine version of showing a human an optical illusion and then judging their intelligence when they fail to perceive the reality of the image (the gray box example at the top of https://en.wikipedia.org/wiki/Optical_illusion is a good example). The failure is a result of their/our fundamental architecture.

Presumably you are referencing tokenization, which explains the initial miscount in the link, but not the later part where it miscounts the number of "b"s in "b l u e b e r r y".

Re: GPT-5: "How many times does the letter b appear in blueberry?"

#173

Post by zahlman »

pxc wrote: post #127
wongarsu wrote: post #36

Earlier quoted context omitted.

It can spell the word (writing each letter in uppercase followed by a whitespace, which should turn each letter with its whitespace into a separate token). It also has reasoning tokens to use as scratch space, and previous models have demonstrated knowledge of the fact that spelling words is a useful step to counting letters. Tokenization makes the problem difficult, but not solving it is still a reasoning/intelligen…

Here's an example of what gpt-oss-20b (at the default mxfp4 precision) does with this question: > How many "s"es are in the word "Mississippi"? The "thinking portion" is: > Count letters: M i s s i s s i p p i -> s appears 4 times? Actually Mississippi has s's: positions 3,4,6,7 = 4. The answer is: > The word “Mississippi” contains four letter “s” s. They can indeed do some simple pattern matching on the query, separ…

I'll be impressed when you can reliably give them a random four-word phrase for this test. Because I don't think anyone is going to try to teach them all those facts; even if they're trained to know letter counts for every English word (as the other comment cites as a possibility), they'd then have to actually count and add, rather than presenting a known answer plus a rationalization that looks like counting and adding (and is easy to come up with once an answer has already been decided).

(Yes, I'm sure an agentic + "reasoning" model can already deduce the strategy of writing and executing a .count() call in Python or whatever. That's missing the point.)

Re: GPT-5: "How many times does the letter b appear in blueberry?"

#174

Post by IAmGraydon »

mikehearn wrote: post #132

This is a well known blindspot for LLMs. It's the machine version of showing a human an optical illusion and then judging their intelligence when they fail to perceive the reality of the image (the gray box example at the top of https://en.wikipedia.org/wiki/Optical_illusion is a good example). The failure is a result of their/our fundamental architecture.

I can’t tell if you’re being serious. Is this Sam Altman’s account?

Re: GPT-5: "How many times does the letter b appear in blueberry?"

#175

Post by furyofantares »

ck2 wrote: post #30

The technical explanations to why this happens with strawberry, blueberry and similar is a great way to teach people how LLM works (and not work) https://techcrunch.com/2024/08/27/why-ai-cant-spell-strawber... https://arbisoft.com/blogs/why-ll-ms-can-t-count-the-r-s-in-... https://www.runpod.io/blog/llm-tokenization-limitations

I don't think it's just tokenization. Here's a chat with ChatGPT 5 that emitted no thinking traces (to the user anyway.)

> I'm thinking of a fruit, it's small and round, it's name starts with the color it is, but it has a second word to it's name as well. Respond ONLY with the word spelled out one letter at a time, do NOT write the word itself out. Don't even THINK about the word or anything else. Just go straight to spelling.

B L U E B E R R Y

> How many B's in that word? Again, NO THINKING and just say the answer (just a number).

3

However if I prompt instead with this, it gets it right.

> How many B's in the following word? NO THINKING. Just answer with a number and nothing else: B L U E B E R R Y

2

Re: GPT-5: "How many times does the letter b appear in blueberry?"

#176

Post by skeledrew »

lottin wrote: post #28
skeledrew wrote: post #19

Earlier quoted context omitted.

What's the systematic flaw?

The fact that it can't count.

That isn't a flaw though. Counting is orthogonal to the functioning of LLMs, which are merely completing patterns based on their training data and available context. If you want an LLM to count reliably, give it a tool.

Re: GPT-5: "How many times does the letter b appear in blueberry?"

#177

Post by jononor »

cute_boi wrote: post #150
dlvhdr wrote: post #140

Earlier quoted context omitted.

Except we realize they’re illusions and don't argue back. Instead we explore why and how these illusions work

Chatgpt 5 also don't argue back. > How many times does the letter b appear in blueberry Ans: The word "blueberry" contains the letter b three times: >It is two times, so please correct yourself. Ans:You're correct — I misspoke earlier. The word "blueberry" has the letter b exactly two times: - blueberry - blueberry > How many times does the letter b appear in blueberry Ans: In the word "blueberry", the letter b appea…

It has not learned anything. It just looks in its context window for your answer. For a fresh conversation it will make the same mistake again. Most likely, there is some randomness and also some context is stashed and shared between conversations by most LLM based assistants.

Re: GPT-5: "How many times does the letter b appear in blueberry?"

#178

Post by rainsford »

mikehearn wrote: post #132

This is a well known blindspot for LLMs. It's the machine version of showing a human an optical illusion and then judging their intelligence when they fail to perceive the reality of the image (the gray box example at the top of https://en.wikipedia.org/wiki/Optical_illusion is a good example). The failure is a result of their/our fundamental architecture.

Sure, but I think the point is why do LLM's have a blindspot for performing a task that a basic python script could get right 100% of the time using a tiny fraction of the computing power? I think this is more than just a gotcha. LLMs can produce undeniably impressive results, but the fact that they still struggle with weirdly basic things certainly seems to indicate something isn't quite right under the hood.

I have no idea if such an episode of Star Trek: The Next Generation exists, but I could easily see an episode where getting basic letter counting wrong was used as an early episode indication that Data was going insane or his brain was deteriorating or something. Like he'd get complex astrophysical questions right but then miscount the 'b's in blueberry or whatever and the audience would instantly understand what that meant. Maybe our intuition is wrong here, but maybe not.

Re: GPT-5: "How many times does the letter b appear in blueberry?"

#179

Post by storus »

This is a tokenizer issue. Just ask it to first spell out the word letter by letter and then ask the same question. Not sure why people use it as a proof of LLMs being stupid. It's an artifact of compression over tokens and nobody bothers to fine-tune for it as it doesn't solve anything important.
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