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Comment by ACCount37 | Hacker News Reader

"The reversal curse", it rarely shows up in practice but you found a case when it did.

The "knowledge landscape" an LLM uses is "directional". It's easy to reach "a quirky music band from Michigan known for colored ties" when you stand at "Tally Hall". But if you stand at "a quirky music band from Michigan known for colored ties", it's harder to reach "Tally Hall" from there. For the "latent knowledge graph" an LLM uses, A->B doesn't cause B->A.

In practice, any "common" facts will have enough "traversal" in both directions that this directional biasing isn't apparent. So it only shows up on this kind of more obscure knowledge.

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If this kind of thing holds true for humans we now may understand synesthesia, perhaps we find ourselves with a large enough study pool to map out clever tricks to influence each other.

It certainly holds true for humans. The brain stores relational information in a sequential pattern that is not automatically reversible. One of the best examples is the alphabet. Everyone learns it in school, so the pattern A->B->C->... is trivial to recite for most people. Now, if I gave you a random letter to start with and asked you to to recite the remaining letters until Z, you'll probably find it is still pretty easy. But if I asked you to cite the letters backwards to A, most people would suddenly struggle with this task because they never learned or used the alphabet that way in school. You need to train specifically to link this kind of information backwards in your brain.

Is the alphabet really the same though? I don't feel like I recall it one letter at a time, as individual facts linking A to B, then B to C, etc, but more as a sound or a phrase. Not unlike recalling a melody. It just seems very different from figuring out what band someone is describing.

Ask someone to name all fifty states, see how far they get. Then start naming places and ask if they're a US state or not. One of these tasks is far more likely to get a 100% hit rate.

Not that I'm too sure about how this applies (or whether it applies at all) to other people as well, but for me personally it's easier to recall information about the band if I'm being told the band's name instead of being told "well, they are known for coloured ties". So, there is certainly some kind of effect described in action.

Now, about alphabet: again, I think it's only me, but when I try to recall it backwards, I can't do that easily. I mean, I can recall it backwards, but I need more time to do that. It's harder. I'm not sure if it's because A links to B, B to C, then C to D and not backwards, or maybe just because in school you learn alphabet from A to Z and not from Z to a - so you're kind of trained to recall it A-->Z way - but it's certainly harder for me.

At the end of the day, though, I think that everyone thinks differently. Everyone is having different internal representations for concepts (such as alphabet), so it’s not surprising that this effect may work differently for different people, or not work at all.

After writing the comment I thought about it some more, and realized when asking myself the question ”what letter comes after R?”, I didn’t immediately know the answer, but I heard ”MNOPQRS” in my head which gave me the answer. So I feel like I know it because I know the rhythm and sound of saying those letters in sequence.

I think what you're saying might be a stretch. I strongly believe the brain holds some information in a sequential pattern -- not necessarily all of it or even the majority of it. There's a book called Moonwalking with Einstein that digs into this precise fact -- you can remember sequences much much better if you associate a visual image with each item in the sequence. Sequential association covers a lot of human knowledge but certainly not the spatial aspects. I think it's a big reason why I think LLM's might not be as smart as we think they are. The complex spatial representations are only encoded implicitly via projection on to textual descriptions.

But it does cover the state described in the top comment. A<-B is never going to be easily retrieved if you only experienced A->B during training, regardless if you are a human neural network or an artificial one. Also, you need to define "spatial" better. This is about logic after all and not geometry. Or topology? It's unclear which context you refer to. It's certainly not the topic of this thread.

Its very true for humans as well. For example, if you ask someone to "name 100 historical figures", they will have a very difficult time. But there are of course hundreds of historical figures people woukd recognize. People who manage to do this still tend to fall into sequences so, i.e., naming all the presidents of America or emperors of Rome. But the broader the category, the more difficult it is to come up with examples.

What's this got to do with synesthesia?

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