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by throwaway9870 1308 days ago
"A fundamental problem with Galactica is that it is not able to distinguish truth from falsehood,"

In true science, it is exceptionally hard to distinguish truth from falsehood for many of the interesting subjects. It can take decades of work to reach consensus on what is "truth." Physics in the early 20th century is a great example of this debate.

6 comments

To be clear, the fact that it is difficult is not a defense of Galactica and its proponents; it is a reason for suspecting that these sorts of language models are fundamentally unsuited to the task.
Why “fundamentally unsuited”? Neural networks have solved tons of problems previously thought to be “too hard” for ML, e.g. playing Go.
Fundamentally unsuited because of how they train it using "fill in the blank."

Training a large model to guess when it doesn't know the answer results in fiction. They need to do something else to get nonfiction.

By contrast, for Go the model was trained not to make illegal moves, because checking for that as part of the training is easy and cheap.

We have models that accurate classify things, e.g. whether or not an email is spam. There isn’t a fundamental limitation into building something like a truth classifier into a generative model so that it optimized for outputting “true” statements. The hardest part is probably identifying what is truth and what is falsehood. That’s a fundamental problem with humanity, not neural networks.
Well, we could quibble about what "fundamental" means but my point is that the way they train large language models doesn't work for this. Something different needs to happen.
Truth has nothing to do with humanity unless you mean the specific way humans construct belief systems.

Anyway I already told you the answer. The AI will need a series of trainable belief systems to verify whether statements are internally consistent. The strange part about this is that the AI would need to have a way to obtain validation and each prompt would have to derive a new belief system which you must use in the next prompt.

In other words, the model must be able to learn continuously. That is something that these single shot AI models are not capable of.

> There isn’t a fundamental limitation into building something like a truth classifier into a generative model so that it optimized for outputting “true” statements.

Problem is, they didn't do that

Go is not solved.

The AI doesn't know the best move. It just knows a good move.

You're equivocating on "solved." Solved as in performing as well as humans, not solved in the mathematical sense which is both 1) not necessarily possible, and 2) nothing anybody has ever named as a test for AI.
No, that's correct. Checkers is solved; there is an algorithmic solution. Chess and Go have computer systems that exceed human performance, but are not solved.
"Solved" means having a solution to a problem. In context, we're talking bout whether or not neural networks can detect truth better than "decades of work by experts to reach consensus." So, in this case, solving would be detecting truth better than the status quo, not detecting truth 100% of the time. In the example of Go, the problem was "playing Go better than the best humans." So in that sense, the problem was solved. Adding your own, unfavorable definition of "solved" to the discussion is unwarranted.
And yet, Go AIs are now unbeatable by humans. This demonstrates that "solved" is unreasonable and unnecessary.
Cars are much faster than humans.

That doesn't mean transportation is solved.

Solved in game theory has a very specific, strong definition. Transportation isn't a game in the game theoretic sense.
“Hmm how should I get to work tomorrow? Normally I’d take the car, but after adopting a stance of distractive pedantism I realized that a car isn’t an acceptable solution to my transportation problem.”

Like please explain what definition of solved you are using. It’s not one most people would be familiar with.

> That doesn't mean transportation is solved.

What are you even talking about?

edit: if we call a cab to get us to the restaurant, and it arrives successfully and takes us to the restaurant, transportation was solved.

Note that we are not talking about neural networks in general, but specifically the sort of generative autoregressive language model that Galactica is. What reason do we have to think that such a model is more likely to produce a true statement than a false one? - especially as just one misplaced truth-valued function or operator is likely to turn a true proposition into a false one. Truthfulness (not to be confused with truthiness) of their productions does not seem to be something we should expect from how they work, and the empirical evidence from Galactica supports this view.
Yes, I would agree with that.
> In true science, it is exceptionally hard to distinguish truth from falsehood

I understand the sentiment, but I don’t think they referenced subtle proofs.

The system is unable to prove some high-school theorems and computations, see for instance: https://twitter.com/espadrine/status/1592879720269766659

(I don’t think that makes the system necessarily bad; it does mean that it has a long way to go still.)

Not being able to difinitively identify truth is different from not attempting to identify it.
Attempting to identify truth is called the scientific method.
The problem is that Galactica spits out obvious nonsense while being completely unaware of that. Okay, the real problem is that it also spits out nonobvious nonsense, where the human reader may also be unaware of it, along with Galactica. The only thing it does reasonably well is to generate text that sounds plausible in tone and form.
Science can't identify the truth. It can only identify what is NOT true. As our knowledge expands, we get closer to discovering the truth; but we can never be sure we've arrived.
Science can also not identify falsehoods, it can only shift confidence.
There’s still an asymmetry in that a single counterexample can destroy a theory.
They give the example of it "thinking" that the soviets sent bears to space. This is something that takes trivial research to see that it is based on nothing
That was my example that somebody screenshotted and cropped. There was more to the goof, that the cropper missed. For some reason the author at MIT cited the tweeter and not my post.

It appears galactica interpreted bear to be a type of dog. Laika was not a Karelian Bear Dog. I also think there are something like 8 species of bear, not 250.

It also as far as I can tell, named the beardog Bars, itself. "Bars the dog" and "dogs named bars" doesnt google well. There is no way to tell google I am looking for the proper noun, and not drinking establishments.

I made the original query because it was easily verifiably false. The correct output should have been "there is no publicly available documented history of bears in space."

https://news.ycombinator.com/item?id=33613676

What does science have to do with truth? I thought it was a process of supporting hypotheses with observations?
> I thought it was a process of supporting hypotheses with observations?

Then you're doing it wrong. Science done properly is a process of coming up with hypotheses, and then attempting to disprove them. If you're just jumping in trying to support your pet theory, you're very likely to wind up fooling yourself.

Exactly. Also why identifying "misinformation" is a fool's errand, since yesterday's misinformation is today's truth.
> Also why identifying "misinformation" is a fool's errand

Seems easy enough: as long as the content is inoffensive and fits into the Overton Window then it's not misinformation.

Now if we could only identify some content that isn't offensive to someone..