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If you're a scientist who works in protein folding (or one of those other areas) and strongly believe that science's goal is to produce falsifiable hypotheses, these new approaches will be extremely depressing, especially if you aren't proficient enough with ML to reproduce this work in your own hands.

If you're a scientist who accepts that probabilist models beat interpretable ones (articulated well here: https://norvig.com/chomsky.html), then you'll be quite happy because this is yet another validation of the value of statistical approaches in moving our ability to predict the universe forward.

If you're the sort of person who believes that human brains are capable of understanding the "why" of how things work in all its true detail, you'll find this an interesting challenge- can we actually interpret these models, or are human brains too feeble to understand complex systems without sophisticated models?

If you're the sort of person who likes simple models with as few parameters as possible, you're probably excited because developing more comprehensible or interpretable models that have equivalent predictive ability is a very attractive research subject.

(FWIW, I'm in the camp of "we should simultaneously seek simpler, more interpretable models, while also seeking to improve native human intelligence using computational augmentation")




The goal of science has always been to discover underlying principles and not merely to predict the outcome of experiments. I don't see any way to classify an opaque ML model as a scientific artifact since by definition it can't reveal the underlying principles. Maybe one could claim the ML model itself is the scientist and everyone else is just feeding it data. I doubt human scientists would be comfortable with that, but if they aren't trying to explain anything, what are they even doing?


That's the aspirational goal. And I would say that it's a bit of an inflexible one- for example, if we had an ML that could generate molecules that cure diseases that would pass FDA approval, I wouldn't really care if scientists couldn't explain the underlying principles. But I'm an ex-scientist who is now an engineer, because I care more about tools that produce useful predictions than understanding underlying principles. I used to think that in principle we could identify all the laws of the universe, and in theory, simulate that would enough accuracy, and inspect the results, and gain enlightenment, but over time, I've concluded that's a really bad way to waste lots of time, money, and resources.


It's not either-or, it's yes-and. We don't have to abandon one for the other.

AlphaFold 3 can rapidly reduce a vast search space in a way physically-based methods alone cannot. This narrowly focused search space allows scientists to apply their rigorous, explainable, physical methods, which are slow and expensive, to a small set of promising alternatives. This accelerates drug discovery and uncovers insights that would otherwise be too costly or time-consuming.

The future of science isn't about AI versus traditional methods, but about their intelligent integration.


Or you can treat AlphaFold as a black box / oracle and work at systems biology level, i.e. at pathway and cellular level. Protein structures and interactions are always going to be hard to predict with interpretable models, which I also prefer.

My only worry is that AlphaFold and others, e.g. ESM, seem to be bit fragile for out-of-distribution sequences. They are not doing a great job with unusual sequences, at least in my experience. But hopefully they will improve and provide better uncertainty measures.


> if we had an ML that could generate molecules that cure diseases that would pass FDA approval, I wouldn't really care if scientists couldn't explain the underlying principles

It’s actually required as part of the submission for FDA approval that you posit a specific Mechanism of Action for why your drug works the way it does. You can’t get approval without it


A substantial proportion of FDA-approved drugs have an unknown mechanism of action - we can handwave about protein interactions, but we have no useful insight into how they actually work. Drug discovery is bureaucratically rigid, but scientifically haphazard.


How much do you believe that the MoA actually matches what is happening in the underlying reality of a disease and its treatment?

Vioxx is a nice example of a molecule that got all the way to large-scale deployment before being taken off the market for side effects that were known. Only a decade before that, I saw a very proud pharma scientist explaining their "mechanism of action" for vioxx, which was completely wrong.


Underlying principles are nice for science, whatever works is nice for engineering. There is plenty of historical precedent where we build stuff that works without knowing exactly why it works.


Me like thee career path. Interesting.


Discovering underlying principles and predicting outcomes is two sides of the same coin in that there is no way to confirm you have discovered underlying principles unless they have some predictive power.

Some had tried to come up with other criteria to confirm you have discovered an underlying principle without predictive power, such as on aesthetics - but this is seen by the majority of scientists as basically a cop out. See debate around string theory.

Note that this comment is summarizing a massive debate in the philosophy of science.


If all you can do is predict an outcome without being able to explain how then what have you really discovered? Asking someone to just believe you can predict outcomes without any reasoning as to how, even if you're always right, sounds like the concept of faith in religion.


The how is actually just further hypotheses. It's turtles all the way down:

There is a car. We think it drives by burning petrol somehow.

How do we test this? We take petrol away and it stops driving.

Ok, so we know it has something to do with petrol. How does it burning the petrol make it drive?

We think it is caused by the burned petrol pushing the cylinders, which are attached to the wheels through some gearing. How do we test it? Take away the gearing and see if it drives.

Anyway, this never ends. You can keep asking questions, and as long as the hypothesis is something you can test, you are doing science.


>There is a car. We think it drives by burning petrol somehow. How do we test this? We take petrol away and it stops driving.

You discovered a principle.

Better example:

There is a car. We don’t know how it drives. We turn the blinkers on and off. It still drives. Driving is useful. I drive it to the store


In the vein of "can a biologist fix a radio" and "can a neuroscientist understand a microprocessor", see https://review.ucsc.edu/spring04/bio-debate.html which is an absolutely wonderful explanation of how geneticists and biochemists would go about reverse-engineering cars.

The best part is where the geneticist ties the arms of all the suit-wearing employees and it has no functional effect on the car.


> what have you really discovered?

You’ve discovered magic.

When you read about a wizard using magic to lay waste to invading armies, how much value would you guess the armies place in whether or not the wizard truly understands the magic being used against them?

Probably none. Because the fact that the wizard doesn’t fully understand why magic works does not prevent the wizard from using it to hand invaders their asses. Science is very much the same - our own wizards used medicine that they did not understand to destroy invading hordes of bacteria.


Exactly! The magic to lay waste to invading armies is packaged into a large flask and magical metal birds are flown to above the army. There the flask is released from the birds bellies and gently glides down. When the flask is at optimum height it releases the power of the sun and all that are beneath it get vaporized. A newer version of this magic is attached to a gigantic fireworks rocket that can fly over whole mountain ranges and seas.


Do you know what the stories say happens to wizards who don't understand magic?

https://youtu.be/B4M-54cEduo?si=RoRZIyWRULUnNKLM


it's still an extremely valuable tool. just as we see in mathematics, closed forms (and short and elegant proofs) are much coveted luxury items.

for many basic/fundamental mathematical objects we don't (yet) have simple mechanistic ways to compute them.

so if a probabilistic model spits out something very useful, we can slap a nice label on it and call it a day. that's how engineering works anyway. and then hopefully someday someone will be able to derive that result from "first principles" .. maybe it'll be even more funky/crazy/interesting ... just like mathematics arguably became more exciting by the fact that someone noticed that many things are not provable/constructable without an explicit Axiom of Choice.

https://en.wikipedia.org/wiki/Nonelementary_integral#Example...


>closed forms (and short and elegant proofs) are much coveted luxury items.

Yes, but we're taking about roughly the opposite of a proof


but in usual natural sciences we don't have proofs, only data and models, and then we do model selection (and through careful experiments we end up with confidence intervals)

and it seems with these molecular biology problems we constantly have the problem of specificity (model prediction quality) vs sensitivity (model applicability), right? but due to information theory constraints there's also a dimension along model size/complexity.

so if a ML model can push the ROC curve toward the magic left-up corner then likely it's getting more and more complex.

and at one point we simply are left with models that are completely parametrized by data and there's virtually zero (direct) influence of the first principles. (I mean that at one point as we get more data even to do model selection we can't use "first principles" because what we know through that is already incorporated into previous versions of the models. Ie. the information we gained from those principles we already used to make decisions in earlier iterations.)

Of course then in theory we can do model distillation, and if there's some hidden small/elegant theory we can probably find it. (Which would be like a proof through contradiction, because it would mean that we found model with the same predictive power but with smaller complexity than expected.)

// NB: it's 01:30 here, but independent of ignorance-o-clock ... it's quite possible I'm totally wrong about this, happy to read any criticism/replies


Isn’t that basically true of most of the fundamental laws of physics? There’s a lot we don’t understand about gravity, space, time, energy, etc., and yet we compose our observations of how they behave into very useful tools.


>there is no way to confirm you have discovered underlying principles unless they have some predictive power.

Yes, but a perfect oracle has no explanatory power, only predictive.


increasing the volume of predictions produces patterns that often lead to underlying principles.


And much of the 20th century was characterized by a very similar progression - we had no clue what the actual mechanism of action was for hundreds of life saving drugs until relatively recently, and we still only have best guesses for many.

That doesn’t diminish the value that patients received in any way even though it would be more satisfying to make predictions and design something to interact in a way that exactly matches your theory.


We were using the compass for navigation for thousands of years, without any clue about what it was doing or why. Ofcourse lot of people got lost cause compasses are not perfect. And the same will happen here. Theory of Bounded Rationality applies.


That ship sailed with Quantum physics. Nearly perfect at prediction, very poor at giving us a concrete understanding of what it all means.

This has happened before. Newtonian mechanics was incomprehensible spooky action at a distance, but Einstein clarified gravity as the bending of spacetime.


I think this relies on either the word “concrete” or a particular choice of sense for “concrete understanding”.

Like, quantum mechanics doesn’t seem, to me, to just be a way of describing how to predict things. I view it as saying substantial things about how things are.

Sure, there are different interpretations of it, which make the same predictions, but, these different interpretations have a lot in common in terms of what they say about “how the world really is” - specifically, they have in common the parts that are just part of quantum mechanics.

The qau that can be spoken in plain language without getting into the mathematics, is not the eternal qau, or whatever.


The goal of science has always been to predict the outcome of experiments, because that's what distinguishes science from philosophy or alchemy or faith. Anyone who believes that they've discovered an underlying principle is almost certainly mistaken; with time, "underlying principles" usually become discredited theories or, sometimes, useful but crude approximations that we teach to high schoolers and undergrads.

Prediction is understanding. What we call "understanding" is a cognitive illusion, generated by plausible but brittle abstractions. A statistically robust prediction is an explanation in itself; an explanation without predictive power explains nothing at all. Feeling like something makes sense is immeasurably inferior to being able to make accurate predictions.

Scientists are at the dawn of what chess players experienced in the 90s. Humans are just too stupid to say anything meaningful about chess. All of the grand theories we developed over centuries are just dumb heuristics that are grossly outmatched by an old smartphone running Stockfish. Maybe the computer understands chess, maybe it doesn't, but we humans certainly don't and we've made our peace with the fact that we never will. Moore's law does not apply to thinking meat.


Kepler famously compiled troves of data on the night sky, and just fitted some functions to them. He could not explain why but he could say what. Was he not a scientist?


He did attempt to explain why. Wikipedia: "On 4 February 1600, Kepler met Tycho Brahe....Tycho guarded his data closely, but was impressed by Kepler's theoretical ideas and soon allowed him more access. Kepler planned to test his theory from Mysterium Cosmographicum based on the Mars data, but he estimated that the work would take up to two years (since he was not allowed to simply copy the data for his own use)."

Mixed it up! I meant Tycho Brahe actually.

Sure he was. And then Newton came along and said it's all because of gravity and Kepler's laws were nothing but his laws of motion applied to planets.

Newton was a bit of a brat but everybody accepted his explanation. Then the problem turned to trying to explain gravity.

Thus science advances, one explanation at a time.


He might not have been able to explain why _but_ I'd bet anything he would have wanted to if he could.


Can underlying principles be discovered using the framework of scientific method? The primary goal of models and theories it develops is to support more experiments and eventually be disproven. If no model can be correct, complete and provable in finite time, then a theory about underlying principles that claims completeness would have to be unfalsifiable. This is reasonable in context of philosophy, but not in natural sciences.

Scientific method can help us rule out what underlying principles are definitely not. Any such principles are not actually up to be “discovered”.

If probabilistic ML comes along and does a decent job at predicting things, we should keep in mind that those predictions are made not in context of absolute truth, but in context of theories and models we have previously developed. I.e., it’s not just that it can predict how molecules interact, but that the entire concept of molecules is an artifact of just some model we (humans) came up with previously—a model which, per above, is probably incomplete/incorrect. (We could or should use this prediction to improve our model or come up with a better one, though.)

Even if a future ML product could be creative enough to actually come up with and iterate on models all on its own from first principles, it would not be able to give us the answer to the question of underlying principles for the above-mentioned reasons. It could merely suggest us another incomplete/incorrect model; to believe otherwise would be to ascribe it qualities more fit for religion than science.


I don't find that argument convincing.

People clearly have been able to discover many underlying principles using the scientific method. Then they have been able to explain and predict many complex phenomena using the discovered principles, and create even more complex phenomena based on that. Complex phenomena such as the technology we are using for this discussion.

Words dont have any inherent meaning, just the meaning they gain from usage. The entire concept of truth is an artifact of just some model (language) we came up with previously—a model which, per above, is probably incomplete/incorrect. The kind of absolute truth you are talking about may make sense when discussing philosophy or religion. Then there is another idea of truth more appropriate for talking about the empirical world. Less absolute, less immutable, less certain, but more practical.


> The kind of absolute truth you are talking about may make sense when discussing philosophy or religion.

Exactly—except you are talking about it, too. When you say “discovering underlying principles”, you are implying the idea of absolute truth where there is none—the principles are not discovered, they are modeled, and that model is our fallible human construct. It’s a similar mistake as where you wrote “explain”: every model (there should always be more than one) provides a metaphor that 1) first and foremost, jives with our preexisting understanding of the world, and 2) offers a lossy map of some part of [directly inaccessible] reality from a particular angle—but not any sort of explanation with absolute truth in mind. Unless you treat scientific method as something akin to religion, which is a common fallacy and philosophical laziness, it does not possess any explanatory powers—and that is very much by design.


Now we come back to words gaining their meaning from usage.

You are assigning meanings to words like "discovering", "principles", and "explain" that other people don't share. Particularly people doing science. Because these absolute philosophical meanings are impossible in the real world, they are also useless when discussing the reality. Reserving common words for impossible concepts would not make sense. It would only hinder communication.


I can see what you mean. Then perhaps you could give a non-circular definition of what you mean by “underlying principles” and how that is different from any other prediction or model to deserve this distinct and quite strong-sounding term? or what you mean by “explain” that is different from “predict” or “model” to warrant such a distinctive term, and where exactly such explanatory activity fits within scientific method?

Communication is inherently circular, and words don't have definitions. But people are often capable of discovering what a particular word means in a particular context. And other people can sometimes help that by giving useful explanations.

Science is pretty much the same. We can often discover how the reality works, and use the discoveries to explain many things. Somehow that keeps happening all the time, even if we can never be fully sure about anything.


Any word can be given a definition, that’s how we communicate. A non-circular definition is a way to define what you mean by a term to another person.

Again: scientific method does not explain. Religion or philosophy are about explaining. Scientific method is about experimentation and making testable predictions. What experiments we perform is determined by how we understand the world, and if there is any subsequent explanation about “how things really are” (a.k.a. “the underlying principles”) then it has nothing to do with scientific method which does not make such claims by design; that is untestable/unfalsifiable beliefs and a product of either philosophical or religious thinking.

Since you insist on using specific words “explain” and “discover”, rather than more conventionally used in science “predict” or “model”, it implies they mean something different to you. I have provided the meanings of “explain” and “discover” I am familiar with, as it applies to the discussion at hand (which is about the philosophy of scientific process, underlying principles and truths about objectively existing reality). If you refuse to identify the meanings you are using those words in, I take it that you concede whatever point you had.


I've never met anyone capable of communicating with well-defined terms. Or giving definitions that actually match the real-word usage of the term. And all definitions are ultimately circular, because the number of words is finite. In any chain of definitions, you will eventually have to use a term you were trying to define.

What you call the scientific method is a philosophical construct that has little to do with actual science. And philosophers disagree on whether it's a good ideal for science. Given that it's neither a good description of science nor a universal ideal for science, I wouldn't focus too much on it when discussing science.


> And all definitions are ultimately circular, because the number of words is finite.

I can’t help thinking I’m talking to an LLM or a troll.

If you use a complex term that needs definition in a casual discussion, it’s most likely none of the words you use in the definition would themselves require definitions—and if this was to happen repeatedly, the conversation would halt long before we would be running out of words. It’s enough to avoid circularity within a couple of levels in good faith.

Anyway, I’m not sure whether we disagree or not or what exactly we are arguing about. My point is “ML making predictions is not a threat to us getting at underlying principles, because natural science (scientific method, predicting things) in general does lead us to any provable facts about those principles, and because ML would make predictions within an incorrect/incomplete model that we gave it.” In that, by “underlying principles” I mean some statements about objective reality. If we are on the same page here, we can continue discussion, otherwise let’s not.


It's an analogy. All communication is ultimately circular, and we can never be sure that we understand the terms the same way as the other party. Still, people often seem to be able to communicate.

Similarly, scientific method cannot discover the underlying principles or explain the nature. It can only rule out principles and explanations. Regardless, science seems to come up with principles and explanations all the time.

And that's because scientific method is not science. It's a theoretical model for a subset of (often ritualized) activities within science. Actual science is more than that. It can do things scientific method cannot, because it's less focused on philosophical ideas such as absolute truth or provable facts.

In my experience, scientific method is like a picture of an elephant drawn from a written description. Drawn by someone who has never seen the animal or a picture of it, and who has no idea what kind of an animal it is. There are some recognizable elements, but it definitely does not look like the real thing.


Sorry, what’s less focused, scientific method or “actual science”?

What if the underlying principles of the universe are too complex for human understanding but we can train a model that very closely follows them?


Then we should dedicate large fractions of human engineering towards finding ethical ways to improve human intelligence so that we can appreciate the underlying principles better.


I spend about 30 minutes reading this thread and links from it: I don't really follow your line of argument. I find it fascinating and well-communicated, the lack of understanding is on me: my attention flits around like a butterfly, in a way that makes it hard for me to follow people writing original content.

High level, I see a distinction between theory and practice, between an oracle predicting without explanation, and a well-thought out theory built on a partnership between theory and experiment over centuries, ex. gravity.

I have this feeling I can't shake that the knife you're using is too sharp, both in the specific example we're discussing, and in general.

In the specific example, folding, my understanding is we know how proteins fold & the mechanisms at work. It just takes an ungodly amount of time to compute and you'd still confirm with reality anyway. I might be completely wrong on that.

Given that, the proposal to "dedicate...engineer[s] towards finding ethical ways to improve...intelligence so that we can appreciate the underlying principles better" begs the question of if we're not appreciating the underlying principles.

It feels like a close cousin of physics theory/experimentalist debate pre-LHC, circa 2006: the experimentalists wanted more focus on building colliders or new experimental methods, and at the extremes, thought string theory was a complete was of time.

Which was working towards appreciating the underlying principles?

I don't really know. I'm not sure there's a strong divide between the work of recording reality and explaining it. I'll peer into a microscope in the afternoon, and take a shower in the evening, and all of a sudden, free associating gives me a more high-minded explanation for what I saw.

I'm not sure a distinction exists for protein folding, yes, I'm virtually certain this distinction does not exist in reality, only in extremely stilted examples (i.e. a very successful oracle at Delphi)


There's a much easier route: consciousness is not included in the discussion...what a coincidence.


That sounds like useful engineering, but not useful science.


I think that a lot of scientific discoveries originate from initial observations made during engineering work or just out of curiosity without rigour.

Not saying ML methods haven't shown important reproducibility challenges, but to just shut them down due to not being "useful science" is inflexible.


What if it turns out that nature simply doesn't have nice, neat models that humans can comprehend for many observable phenomena?


I read an article about the "unreasonable effectiveness of mathematics" that it was basically the result of a drunk looking for his keys under a lamp post because that's where the light is. We know how to use math to model parts of the world, and every where we look, there's _something_ we can model with math, but that doesn't mean that there's all there is to the universe. We could be understanding .0000001% of what's out there to understand, and it's the stuff that's amenable to mathematical analysis.


The ML model can also be an emulator of parts of the system that you don't want to personally understand, to help you get on with focusing on what you do want to figure out. Alternatively, the ML model can pretend to be the real world while you do experiments with it to figure out aspects of nature in minutes rather than hours-days of biological turnaround.


The machine understands, we do not, and so it is not science?

Can we differentiate?


Maybe the science of the past was studying things of lesser complexity than the things we are studying now.


If have an oracle that can predict the outcome of experiments does it _matter_ if you understand why?


AFAIK in wet science you need (or needed) to do tons of experimentations with liquids with specific molar compositions and temperatures splurging in and out of test tubes - basically just physically navigating a search space. I would view an AI model with super powerful guestimation capability as a much faster way of A) cutting through search space B) providing accidental discoveries while at it

Now, if we look at history of science and technology, there is a shit ton of practical stuff that was found only by pure accident - discoveries of which could not be predicted from any previous theory.

I would view both A) and B) as net positives. But our teaching of the next generation of scientists needs to adapt.

The worst case scenario is of course that the middle management driven enshittification of science will proceed to a point where there are only few people who actually are scientists and not glorified accountants. But I’m optimistic this will actually super charge science.

With good luck we will get rid of the both of the biggest pathologies in modern science - 1. number of papers published and referred as a KPI 2. Hype driven super politicized funding where you can focus only one topic “because that’s what’s hot” (i.e. string theory).

The best possible outcome is we get excitement and creativity back into science. Plus level up our tech level in this century to something totally unforeseen (singularity? That’s just a word for “we don’t know what’s gonna happen” - not a specific concrete forecasted scenario).


> singularity? That’s just a word for “we don’t know what’s gonna happen” - not a specific concrete forecasted scenario

It's more specific than you make it out. The singularity idea is that smart AIs working on improving AI will produce smarter AIs, leading to an ever increasing curve that at some point hits a mathematical singularity.


No it's not specific at all in predicting technological progress, which was the point of my comment.

Nobody knows what singularity would actually mean from the point of view of specific technological development.


they offered a good tool for science... so this is a part of science.


> If you're the sort of person who believes that human brains are capable of understanding the "why" of how things work in all its true detail, you'll find this an interesting challenge- can we actually interpret these models, or are human brains too feeble to understand complex systems without sophisticated models?

I think chess engines, weirdly enough, have disabused me of this notion.

There are lots of factors a human considers when looking at a board. Piece activity. Bishop and knight imbalances. King safety. Open and semi-open file control. Tempo. And on and on.

But all of them are just convenient shortcuts that allow us to substitute reasonable guesses for what really matters: exhaustively calculating a winning line through to the end. “Positional play” is a model that only matters when you can’t calculate trillions of lines thirty moves deep, and it’s infinitely more important that a move survives your opponent’s best possible responses than it is to satisfy some cohesive higher level principle.


I don't understand why you would draw this conclusion. The deep search you describe is an algorithm that humans can understand perfectly fine. Humans just can't solve it in their heads and need to let a computer handle the number crunching. Just like a scientist may understand the differential equations to describe a system perfectly fine, but require a computer to approximate the solution for an initial value problem.


“Knowing” that some line works to some ridiculous depth is different than understanding how and why.

And at some level the answer is simply “because every possible refutation fails” and there is no simpler pattern to match against nor intuition to be had. That is the how and why of it.


The scientist can understand “how” the model works, how many layers there are, that each neuron has a weight, that some are connected… Parent comment and yours show that “understanding” is a fuzzy concept.


Chess engines actually do both now. They have ML models to evaluate positions, essentially a much more advanced version of your positional description, and deep calculations.


That might be the best we can practically achieve with technology, but the point stands. If positional evaluation says one thing but an exhaustive analysis of lines finds a solution 60 moves deep, that one is going to win.


Humans also do search. Also, engines arent doing an exhaustive search when they are 20 moves deep. They heavily prune.


Yes, I understand how chess engines work.

Ignore the existence of engines for a moment. The reason a particular line works, at the end of the day, is simply because it does. Just because we have heuristics that help us skip a lot of evaluation doesn’t mean the heuristics have intrinsic meaning within the game. They don’t.

They’re shortcuts that let us skip having to do the impossible. The heuristics will always lose to concrete analysis to a deep enough depth.

And that’s my point. We come up with models that give us an intuition for “why” things are a certain way. Those models are inarguably helpful toward having a gut feeling. But models aren’t the thing itself, and every model we’ve found breaks down at some deeper point. And maybe at some level things simply “are” some way with no convenient shorthand explanation.


So your point is that we are not omnipotent? Ok.


Because of our limitations, we have to compress reality more in order to reason about it. This means we're blind to some ideas that computers are not. Just like a depth 1 chess engine can't see what's happening at depth 3 but has to make an imperfect guess.

Fine tuned LLMs can play chess at grandmaster levels.

So its clear that there is in fact 'deeper patterns to chess' that allow one to play very well, without any search required (Since LLMs cannot search). Its just that those patterns are probably rather different to human understood ones.


I'm in the following camp: It is wrong to think about the world or the models as "complex systems" that may or may not be understood by human intelligence. There is no meaning beyond that which is created by humans. There is no 'truth' that we can grasp in parts but not entirely. Being unable to understand these complex systems means that we have framed them in such a way (f.e. millions of matrix operations) that does not allow for our symbol-based, causal reasoning mode. That is on us, not our capabilities or the universe.

All our theories are built on observation, so these empirical models yielding such useful results is a great thing - it satisfies the need for observing and acting. Missing explainability of the models merely means we have less ability to act more precisely - but it does not devalue our ability to act coarsely.


But the human brain has limited working memory and experience. Even in software development we are often teetering at the edge of the mental power to grasp and relate ideas. We have tried so much to manage complexity, but real world complexity doesn't care about human capabilities. So there might be high dimensional problems where we simply can't use our brains directly.


A human mind is perfectly capable of following the same instructions as the computer did. Computers are stupidly simple and completely deterministic.

The concern is about "holding it all in your head", and depending on your preferred level of abstraction, "all" can perfectly reasonably be held in your head. For example: "This program generates the most likely outputs" makes perfect sense to me, even if I don't understand some of the code. I understand the system. Programmers went through this decades ago. Physicists had to do it too. Now, chemists I suppose.


Abstraction isn't the silver bullet. Not everything is abstractable.

"This program generates the most likely outputs" isn't a scientific explanation, it's teleology.


"this tool works better than my intuition" absolutely is science. "be quiet and calculate" is a well worn mantra in physics is it not?


“calculate” in that phrase, refers to doing the math, and the understanding that that entails, not pressing the “=“ button on a calculator.


Why do you think systems of partial differential equations (common in physics) are somehow provide more understanding than the corresponding ML math (at the end of the day both can produce results using a lots of matrix multiplications).


... because people understand things about what is described when dealing with such systems in physics, and people don't understand how the weights in ML learned NNs produce the overall behavior? (For one thing, the number of parameters is much greater with the NNs)


Looking at Navier-Stokes equations tells you very little about the weather tomorrow.

Sure. It does tell you things about fluids though.

What is an example of something that isn't abstractable?


Stuff that we can't program directly, but can program using machine learning.

Speech recognition. OCR. Reccomendation engines.

You don't write OCR by going "if there's a line at this angle going for this long and it crosses another line at this angle then it's an A".

There's too many variables and influence of each of them is too small and too tightly coupled with others to be able to abstract it into something that is understandeable to a human brain.


AI arguably accomplishes this using some form of abstraction though does it not?

Or, consider the art word broadly, artists routinely engage in various forms of unusual abstraction.


> AI arguably accomplishes this using some form of abstraction though does it not?

It's unabstractable for people, because the most abstract model that works still has far too many variables for our puny brains.

> artists routinely engage in various forms of unusual abstraction

Abstraction in art is just another, unrelated meaning of the word. Like execution of a program vs execution of a person. You could argue executing the journalist for his opinions isn't bad, because execution of mspaint.exe is perfectly fine, but it won't get you far :)


> It's unabstractable for people, because the most abstract model that works still has far too many variables for our puny brains.

Abstraction doesn't have to be perfect, just as "logic" doesn't have to be.

> Abstraction in art is just another, unrelated meaning of the word.

Speaking of art: have you seen the movie The Matrix? It's rather relevant here.


This is just wrong.

While computer operations in solutions are computable by humans, the billions of rapid computations are unachievable by humans. In just a few seconds, a computer can perform more basic arithmetic operations than a human could in a lifetime.


I'm not saying it's achievable, I'm saying it's not magic. A chemist who wishes to understand what the model is doing can get as far as anyone else, and can reach a level of "this prediction machine works well and I understand how to use and change it". Even if it requires another PhD in CS.

That the tools became complex is not a reason to fret in science. No more than statistical physics or quantum mechanics or CNN for image processing - it's complex and opaque and hard to explain but perfectly reproduceable. "It works better than my intuition" is a level of sophistication that most methods are probably doomed to achieve.


"There is no 'truth' that we can grasp in parts but not entirely."

The value of pi is a simple counterexample.


We can predict the digits of pi with a formula, to me that counts as grasping it



> There is no 'truth' that we can grasp in parts but not entirely

It appears that your own comment is disproving this statement


> There is no 'truth' that we can grasp in parts but not entirely.

If anyone actually thought this way -- no one does -- they definitely wouldn't build models like this.


> ... and strongly believe that science's goal is to produce falsifiable hypotheses, these new approaches will be extremely depressing

I don't quite understand this point — could you elaborate?

My understanding is that the ML model produces a hypothesis, which can then be tested via normal scientific method (perform experiment, observe results).

If we have a magic oracle that says "try this, it will work", and then we try it, and it works, we still got something falsifiable out of it.

Or is your point that we won't necessarily have a coherent/elegant explanation for why it works?


There is an issue scientifically. I think this point was expressed by Feynman: the goal of scientific theories isn’t just to make better predictions, it’s to inform us about how and why the world works. Many ancient civilizations could accurately predict the position of celestial bodies with calendars derived from observations of their period, but it wasn’t until Copernicus proposed the heliocentric model and Galileo provided supporting observations that we understood the why and how, and that really matters for future progress and understanding.


I agree the how/why is the main driving goal. That's kinda why I feel like this is not depressiong news — there's a new frontier to discover and attempt to explain. Scientists love that stuff (:

Knowing how to predict the motion of planets but without having an underlying explanation encourages scientists to develop their theories. Now, once more, we know how to predict something (protein folding) but without an underlying explanation. Hurray, something to investigate!

(Aside: I realize that there are also more human factors at play, and upsetting the status quo will always cause some grief. I just wanted to provide a counterpoint that there is some exciting progress represented here, too).


I was mainly responding to the claim that these black boxes produce a hypothesis that is useful as a basis for scientific theories. I don’t think it does, because it offers no explanation as to the how and why, which is as we agree the primary goal. It doesn’t provide a hypothesis per se, just a prediction, which is useful technologically and should indicate that there is more to be discovered (see my response to the sibling reply) scientifically but offers no motivating explanation.


But we do know why, it's just not simple. The atoms interact with one another because of a variety of fundamental forces, but since there can be hundreds of thousands of atoms in a single protein, it's plainly beyond human comprehension to explain why it folds the way it does, one fundamental force interaction at a time.


Fair. I guess the interesting thing for protein folding research then is that there appears to be a way to approximate/simplify the calculations required to predict folding patterns that doesn’t require the precision of existing folding models and software. In essence, AlphaFold is an existence proof that there should be a way to model protein folding more efficiently.


People will be depressed because they spent decades getting into professorship positions and publishing papers with ostensible comprehensible interpretations of the generative processes that produced their observations, only to be "beat" in the game by a system that processed a lot of observations and can make predicts in a way that no individual human could comprehend. And those professors will have a harder time publishing, and therefore getting promoted, in the future.

Whether ML models produce hypotheses is something of an epistemiological argument that I think muddies the waters without bringing any light. I would only use the term "ML models generate predictions". In a sense, the model itself is the hypothesis, not any individual prediction.


What if our understanding of the laws of the natural sciences are subtly flawed and AI just corrects perfectly for our flawed understanding without telling us what the error in our theory was?

Forget trying to understand dark matter. Just use this model to correct for how the universe works. What is actually wrong with our current model and if dark matter exists or not or something else is causing things doesn't matter. "Shut up and calculate" becomes "Shut up and do inference."


All models are wrong, but some models are useful.


The black box AI models could calculate epicycles perfectly so the middle ages Catholic Church could say just use those instead of being a geocentrrism denier.

High accuracy could result from pretty incorrect models. When and where that woukd then go completely off the rails is difficult to say.


ML is accustomed with the idea that all models are bad, and there are ways to test how good or bad they are. It's all approximations and imperfect representations, but they can be good enough for some applications.

If you think carefully humans operate in the same regime. Our concepts are all like that - imperfect, approximative, glossing over some details. Our fundamental grounding and test is survival, an unforgiving filter, but lax enough to allow for anti-vaxxer movements during the pandemic - survival test is not testing for truth directly, only for ideas that fail to support life.


Also lax enough for the hilarious mismanagement of the situation by "the experts". At least anti-vaxxers have an excuse.


Wouldn’t learning new data and results give us more hints to the true meaning of the thing? I fail to see how this is a bad thing in anyone’s eye.


There have been times in the past when usable technology surpassed our scientific understanding, and instead of being depressing it provided a map for scientific exploration. For example, the steam engine was developed by engineers in the 1600s/1700s (Savery, Newcomen, and others) but thermodynamics wasn’t developed by scientists until the 1800s (Carnot, Rankine, and others).


I think the various contributors to the invention of the steam engine had a good idea of what they were trying to do and how their idea would physically work. Wikipedia lists the prerequisites as the concepts of a vacuum and pressure, methods for creating a vacuum and generating steam, and the piston and cylinder.


That's not too different from the alpha fold people knowing that there's a sequence to sequence translation, that an enormous number of cross-talk happens between the parts of the molecule, that if you get the potential fields just right, it'll fold in the way nature intended. They're not just blindly fiddling with a bunch of levers. What they don't know is the individual detailed interactions going on and how to approximate them with analytical equations.


What always struck me about Chomskyists is that they chose a notion of interpretable model that required unrealistic amounts of working interpretation. So Chomsky grammars have significant polynomial memory and computational costs for grammars as they approach something resembling human grammar. And you say, ok, the human brain can handle much more computation than that, and that's fine. But (for example) context-free grammars aren't just O(n^3) in computational cost; for a realistic description of human language they're O(n^3) in human-interpretable rules.

Other Chomsky-like models of human grammars have different asymptotic behavior and different choices of n, but the same fundamental problem; the big-O constant factor isn't neurons firing but rather human connections between the n inputs. How can you conceive of human minds being able to track O(n^3) (or whatever) cost where that n is everything being communicated -- words, concepts, symbols, representations, all that jazz and the polynomial relationships between them?

But I feel an apology is in order: I've had quite a few beers before coming home, and it's probably a mistake to try to express academically charged and difficult views on the Internet while in an inebriated state. Probably the alcohol has substantially decreased my mental computational power. However, it has only mildly impaired my ability to string together words and sentences in a grammatically complex fashion. In fact, I often feel that the more sober and clear-minded I am, the simpler my language is. Maybe human grammar is actually sub-polynomial. I have observed the same in ChatGPT; the more flowery and wordy it has become over time, the dumber its output.


There is a ballmer peak for pontificating.

As an aside but relevant to your point, my entire introduction to DNA and protein analysis was based on Chomsky grammars. My undergrad thesis advisor David Haussler handed me a copy of an article by David Searls "The Linguistics of DNA" (https://www.scribd.com/document/461974005/The-Linguistics-of...) . At the time, Haussler was in the middle of applying HMMs and other probabilistic graphical models to sequence analysis, and I knew all about DNA as a molecule, but not how to analyze it.

Searls paper basically walks through Chomsky's hierarchy, and how to apply it, using linguistic techniques to "parse" DNA. It was mind-bending and mind-expanding for me (it takes me a long time to read papers, for example I think I read this paper over several months, learning to deal with parsing along the way). To this day I am astounded at how much those approaches (linguistics, parsing, and grammars) have evolved- and yet not much has changed! People were talking about generative models in the 90s (and earlier) in much the same way we treat LLMs today. While much of Chomsky's thinking on how to make real-world language models isn't particuarly relevant, we still are very deeply dependent on his ideas for grammar...

Anyway, back to your point. While CFGs may be O(n*3) I would say that there is a implicit, latent O(n) parseable grammar underlying human linguistics, and our brains can map that latent space to its own internal representation in O(1) time, where the n roughly correlates to the complexity of the idea being transferred. It does not seem even remotely surprising that we can make multi-language models that develop their own compact internal representation that is presumably equidistant from each source language.


For some, this conversation started when the machine derived four colour map proof was announced which is almost 5 decades ago in 1976


> If you're the sort of person who believes that human brains are capable of understanding the "why" of how things work in all its true detail

This seems to me an empirical question about the world. It’s clear our minds are limited, and we understand complex phenomena through abstraction. So either we discover we can continue converting advanced models to simpler abstractions we can understand, or that’s impossible. Either way, it’s something we’ll find out and will have to live with in the coming decades. If it turns out further abstractions aren’t possible, well, enlightenment thought had lasted long enough. It’s exciting to live at a time in humanity’s history when we enter a totally uncharted new paradigm.


> can we actually interpret these models, or are human brains too feeble to understand complex systems without sophisticated models?

I think we will have to develop a methodology and supporting toolset to be able to derive the underlying patterns driving such ML models. It's just too much for a human to comb through by themselves and make sense of.


So the work to simplify ML models, reduce dimensions, etc. becomes the numeric way to seek simple actual scientific models. Scientific computing and science become one.


Do you think a model will also be able to truly comprehend everything too ?


The goal of science should always be to seek good explanations hard to vary.




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