Logical reasoning is needed in a wide range of NLP tasks. Can a BERT model be trained end-to-end to solve logical reasoning problems presented in natural language? We attempt to answer this question in a confined problem space where there exists a set of parameters that perfectly simulates logical reasoning. We make observations that seem to contradict each other: BERT attains near-perfect accuracy on in-distribution test examples while failing to generalize to other data distributions over the exact same problem space. Our study provides an explanation for this paradox: instead of learning to emulate the correct reasoning function, BERT has in fact learned statistical features that inherently exist in logical reasoning problems. We also show that it is infeasible to jointly remove statistical features from data, illustrating the difficulty of learning to reason in general. Our result naturally extends to other neural models and unveils the fundamental difference between learning to reason and learning to achieve high performance on NLP benchmarks using statistical features.
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I think today's AI researchers' preoccupation with just learning directly from data in an effort to achieve AGI is understandable, because this data-driven approach has generated results that are far more impressive than all the previous approaches that involved humans implementing concepts / reverse-engineering how the human mind works in order to create a truly intelligent machine (see Sutton's Bitter Lesson http://www.incompleteideas.net/IncIdeas/BitterLesson.html). Because of the demonstrated success of these systems, a popular hypothesis is that maybe increasingly large amounts of data and computation is enough to solve all the remaining problems in AI.
Can abstract…
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concepts such as causality be "learned" directly from data? It's an important question, but answering such a question might not be necessary to train an AI model to make good predictions. It might be enough to show an AI model videos of billiard games, then to pause at random points in those videos and ask the model to predict what would happen next. (For example, the video could be paused at the very moment one billiard ball hit a second billiard ball.) If the AI model manages to correctly predict what the very next frame looks like (the second billiard ball starts to move), and it produces similar predictions in analogous situations of things colliding with other things, then it arguably "understands" this form of causality. If it fails to predict the next frame, the neural network training algorithm can adjust the neural network's neuron weights such that it will be inclined to make the correct prediction in the future. Over the course of many of these predictions and adjustments, over thousands or millions of hours of video, the expectation is that a system will emerge that is capable of making correct predictions in a variety of situations, as that means it has managed to develop general rules or "understand" causality.
As the AI developer I wouldn't even have to be aware of e.g. why a billiard ball could cause another to move, because if my neural network can make accurate predictions in such situations, it's useful and demonstrates understanding. Such an understanding may in fact require the neural network to internally represent such concepts as causality / laws of physics (as your discussion implies), but I would not have to concern myself with the details of how the neural network actually perceives the world, if the predictions are consistent and reliable. With large amounts of data and computation, the neural network weights could be tuned to create a network that is able to make good predictions in any domain at all. That's the idea anyway.
Despite the optimism I think that there's something missing. There are simpler problem domains, like SimpleLogic (https://arxiv.org/abs/2205.11502), where researchers show that learning logical reasoning from data is apparently impossible in practice, because various spurious statistical correlations in data strongly encourage ML systems to learn incorrect approaches to solving logic problems, sort of like how using incorrect methods can sometimes still give you the correct answer in maths problems. The problem here is that the incorrect method might give valid answers in some situations, but will absolutely give wrong answers in others. I think that this issue is a severe and possibly insurmountable flaw of the current approach to AI, despite the impressive results we've seen so far, because real-world data such as video, images, and text, is far messier than artificial examples used in this research paper. But who knows what the future will bring?
seL4 has seen use in military projects, including UAVs and drones. It's been endorsed by the Linux Foundation. I wouldn't really call it an academic proof of concept at this point.
Regarding logic problems, I've tested GPT-4 and Bard. Both fail some pretty typical logic problems, because that's not what they were designed to solve. They match patterns. This is great for story telling, summarizing, and replication of plausible prose based on its training. But, these systems break down in subtle ways when prompted to perform logical reasoning. Don't take my word for it though.
https://arxiv.org/abs/2205.11502
Even logical reasoning we take for granted, like variable…
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substitution, is difficult for an LLM.
https://paperswithcode.com/paper/the-reversal-curse-llms-tra...
I will agree with you, however, that making any predictions about where this technology will go in the future is difficult. My experience tells me that the current modeling of LLMs are on the wrong track, but a lot of money is being invested in this technology. If there is a way to improve it incrementally, and if these incremental improvements can cause a significant paradigm shift, then perhaps I'll be proven wrong.
As for my field experience using formal methods, I currently build system software and firmware. I use model checking daily. I have built up abstract machine models using Coq and Lean 4 to constructively build data structures and algorithms that I can extract to C and machine code. Typically, these would include software cryptographic primitives, graph algorithms, data structures like binary trees, and file systems. I'd say that model checking covers about 95% of my usage of formal methods, and constructive proofs cover the remaining 5%. I use a combination of CBMC and Z3 to model check the software and firmware that I write. CBMC is used to model check software in C. Z3 is used to model check assembler and machine code.
I'm trying to interpret what you said in a strong, faithful interpretation. To that end, when you say "surely it will improve", I assume what you mean is, it will improve with regards to being trustworthy enough to use in contexts where hallucination is considered to be a deal-breaker. What you seem to be pushing for is the much weaker interpretation that they'll get better at all, which is well, pretty obviously true. But that doesn't mean squat, so I doubt that's what you are saying.
On the other hand, the problem of getting people to trust AI in sensitive contexts where there could be a lot at stake is non-trivial, and I believe people will definitely demand…
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better-than-human ability in many cases, so pointing out that humans hallucinate is not a great answer. This isn't entirely irrational either: LLMs do things that humans don't, and humans do things that LLMs don't, so it's pretty tricky to actually convince people that it's not just smoke and mirrors, that it can be trusted in tricky situations, etc. which is made harder by the fact that LLMs have trouble with logical reasoning[1] and seem to generally make shit up when there's no or low data rather than answering that it does not know. GPT-4 accomplishes impressive results with unfathomable amounts of training resources on some of the most cutting edge research, weaving together multiple models, and it is still not quite there.
If you want to know my personal opinion, I think it will probably get there. But I think in no way do we live in a world where it is a guaranteed certainty that language-oriented AI models are the answer to a lot of hard problems, or that it will get here really soon just because the research and progress has been crazy for a few years. Who knows where things will end up in the future. Laugh if you will, but there's plenty of time for another AI winter before these models advance to a point where they are considered reliable and safe for many tasks.
[1]: https://arxiv.org/abs/2205.11502
> but LLMs reason just fine.
There is a lot of research that shows they have trouble reasoning. Folks working with LLMs and building them agree that they can't reason, yet pop-sci folks religiously insist they can reason.
This is not even a controversial topic.
https://arxiv.org/abs/2205.11502
Reminds me of this comic:
https://www.smbc-comics.com/comic/2010-01-31
> it seems that this merely exposes the normal operation. Insufficient images of that person prevented it from abstracting the person components from the background
yes my point was that this total failure to abstract (or slice or average or whatever it is that it usually seems to do) appears to me to be neither the intended nor typical mode of operation
> children under 1/10 of that age, who have seen only 10% of those images would not make the same kinds of mistakes
but then children aren't being fed a stream of unrelated images. they're receiving a wide array of real time sensory input from an environment they're actively operating in
consider your examples of the lack…
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of higher level understanding about how the parts of a human "fit together". what practical experience do these models have that could actually convey such an understanding? deriving a proper understanding of mechanics in 3D from one million independent 2D still frames of human hands performing various tasks seems like it should be extremely difficult at best
> Could this be trained in? I expect so, but I think it would require multiple engines
I think it requires a different sort of training algorithm entirely. work such as https://arxiv.org/abs/1803.10122 suggests to me that there might be little difference between the human ability to abstract and lossy compression. at the same time work such as https://arxiv.org/abs/2205.11502 makes it apparent that in many cases this sort of generalization simply does not happen the way we'd like
> the neuron/synapse/neurotransmitter and brainstem/midbrain/cerebellum micro & macro-architectures are vastly different than the computer training models. So, I think we can be confident that something different is happening
something being architected differently doesn't necessarily mean that the higher level functionality is any different
moreover, in purely functional terms how do you propose to distinguish something that's different from something that's incomplete? ie a smaller piece of a larger whole? if someone constructs for example a passable digital model of the visual cortex of the mouse or human or other animal that's still only a single small piece of the whole
so who is and how are we to say that we either have or haven't achieved a meaningful form of abstraction versus merely averaging bits of the training set together? at this point I'm not actually clear where the line between those two things even lies
I've only skimmed but it seems like the general idea is sound, that neural networks are good at pattern matching and that shallow pattern matching is only one aspect of "deep thought", logical reasoning being the other one.
I'm confused though, they give examples of Go and Chess but, as far as I understand, this is exactly what the author is saying doesn't exist. AlphaGo, Deep Blue, etc, all use neural networks to weight how to traverse the minimax tree [0]. The minimax algorithm/tree is precisely the "logical reasoning". The neural network is "just" prioritizing the path to take.
Anyway, like I said, the reasoning is sound. I just read a paper specifically about this…
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breakdown, called "On the Paradox of Learning to Reason from Data" by Zhang, et all [1] where they construct a synthetic data set based on some simple logical rules and then try to train a neural network to recapture the underlying logic (spoiler alter, it fails). From their paper:
"""
Our study provides an explanation for this paradox: instead of learning to emulate the correct reasoning function, BERT has, in fact, learned statistical features that inherently exist in logical reasoning problems. We also show that it is infeasible to jointly remove statistical features from data, illustrating the difficulty of learning to reason in general.
"""
[0] https://en.wikipedia.org/wiki/Minimax
[1] https://arxiv.org/abs/2205.11502
> “Humans are actually reasoning. LLMs are not.” Again, how would you measure such a thing?
Wow. Leave it to HN commenters to arrogantly ignore research by those in the field.
1. LLMs can't reason or calculate. This is why we have ToolFormer or Plugins in the first place. Even GTP-4 is bad at reasoning. Maybe GPT-infinity will be good? Who knows.
2. They call out to tools that can calculate or reason (Humans built these tools not aliens)
3. How can humans do 2 if they can't reason?
https://arxiv.org/abs/2205.11502
More informal presentation here:
https://bdtechtalks.com/2022/06/27/large-language-models-log...
Artificial intelligence (AI) researchers have been developing and refining large language models (LLMs) that exhibit remarkable capabilities across a variety of domains and tasks, challenging our understanding of learning and cognition.
Recent work has demonstrated substantial gains on many NLP tasks and benchmarks by pre-training on a large corpus of text followed by fine-tuning on a specific task.
The Fermi paradox is the conflict between an expectation of a high {\em ex ante} probability of intelligent life elsewhere in the universe and the apparently lifeless universe we in fact observe.
Despite their massive size, successful deep artificial neural networks can exhibit a remarkably small difference between training and test performance.