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by evdev 2227 days ago
It's cargo-culting physics to assert that there are a set of "high level" laws in some area without having in hand the reductionist mechanics.

This cart-before-the-horse is so pervasive in social sciences, and developing sciences like neuroscience, that it's understandable one would ask why history can't get in on the action.

The glib invocation of phlogiston theory is telling. The essence of phlogiston theory is not wrong!

5 comments

I strongly disagree with this view. I sympathize with you that it's probably true that scientists are inclined to cargo-cult their science after physics. But the endeavor here is not wrong, so even if it's cargo-cult, it's good.

Science's primary objective is to find models. A model should do predictions, and then scientist should collect data of interest, and make sure the data isn't falsified by the model's predictions. Any scientist who cannot do predictions, and verify that data doesn't contradict predictions, is no scientist at all.

Once you have models, it's simply too tempting to formalize them and build mathematical theories for them. If nothing, for computational advantage, so you can make computers make predictions, this way you can eliminate human errors. So, it seems like any science will eventually build models that can generate predictions from first principles.

It is one thing to claim the entire human history can be predicted from first principles of a theory X. Clearly, we have no such X. Maybe we never will. It's another, and totally reasonable thing, to build a theory X from first principles that correctly predicts some data.

No one has ever built a historical model that predicts the future with any accuracy. There are plenty of overfit models that "predict" the past, but none hold up on new events.

Interesting book on the topic from the world's leading researcher, if you're curious: https://www.amazon.com/Superforecasting-Art-Science-Predicti...

Does Moore's law count as a historical model?

Perhaps it is too recent and limited in scope,

but it is about, like, some measurable things about society, which is based on past observations, and it has been somewhat predictive? (though, perhaps it being somewhat predictive has been in part due to it becoming somewhat prescriptive?)

Moore's law is more of an economic necessity. Circuits get cheaper to run, cheaper to make, and faster the more you shrink them, so you just keep shrinking them. This was observed by Carver Mead way back in the middle of the 20th century.

Moore's law requires an average of 3% increase a month in the number of transistors packed on a chip. With a few hundred thousand people working on the problem, that's not crazy. Of course it's going to be spikey, but combined over the lifetime of a chip project...

I don't know that Moore's Law is what most people would mean by a historical law, but it has held up surprisingly well even for a non-historical law :)
Just because it has not been done before, doesn't mean trying to do so (i.e. make a science of history) is invalid or just cargo culting. Especially since GP referred to other social sciences, and named neuroscience. It has not been done for history, maybe it never will be. I don't think generalizing this to all social sciences holds up. Surely there are some falsifiable predictions of psychology, sociology etc that has been tested.
The social sciences don't work like the hard sciences though. And the primary reason for this is because humans, unlike say, atoms or molecules, are not independent objects. They are subjects with agency and can react and change their behaviour in response to what your models predict about them. Essentially predictions can become self-fulfilling prophecies.
> I sympathize with you that it's probably true that scientists are inclined to cargo-cult their science after physics. But the endeavor here is not wrong, so even if it's cargo-cult, it's good.

Having been trained as a physicist and then worked as a biologist and dabbled in history, it isn't good. Physics cannot be used as the ideal of sciences because it is an extremely strange science. Consider: physics deal with simple systems with only a few essential observables that can be repeatably measured. History deals with very complicated systems with an inordinate number of possible observables none of which can be repeatably measured. Why would you expect them to resemble each other? I actually wrote a book about this...

> Science's primary objective is to find models. A model should do predictions, and then scientist should collect data of interest, and make sure the data isn't falsified by the model's predictions. Any scientist who cannot do predictions, and verify that data doesn't contradict predictions, is no scientist at all.

A model is supposed to recapitulate observations. Prediction is only relevant in the case of repeatable observations or the discovery of new observables. Astrophysics and history don't get the former, but you will find prediction in both in the latter case...but once you've measured it, it's not prediction anymore.

> Once you have models, it's simply too tempting to formalize them and build mathematical theories for them.

People do this to a limited extent with toy models, but the relationships among observables in history that you can get from the historical record tend to be fairly simple and rough, while the number of observables is enormous, so formal modelling doesn't buy you much. When people have done this on a large scale, you get the Club of Rome...trying to peer a few decades into the future with an enormously complicated model.

> It's another, and totally reasonable thing, to build a theory X from first principles that correctly predicts some data.

First principles are overrated, and I think the training of physicists overemphasizes them. In condensed matter there's a phrase, "more is different." We can go from atomic descriptions to macroscopic ones...in very, very simple cases. History has no such simple cases. You always have a huge number of parameters, which leads you back to the old adage that with three parameters you can draw an elephant, and with four you can make him wag his tail. There's too much slop for a model from first principles predicting things in history to be interesting.

Boyle's gas law can be discovered without knowing anything about a kinetic theory of gases or quantum mechanics. You can discover "high level" laws (effective but incomplete approximations to reality) without knowing how to model the system components at the individual level. Inexact, sure, but with (limited) analytic and predictive power.

In Biology you don't know how all the cells of a population of wolves and rabbits works or his present state. But you can use predator-prey models to predict (at some level) population fluctuations.

If science awaited to have a complete description at the most fundamental level to make predictions, there will be no progress at all. By discovering "high level" laws you can get closer to "lower level" ones, as Boyle is an step to get to QM (what's the cart and what's the horse). Maybe all "laws" are emergent and our models only approximations, and there is no fundamental ones to be discovered, so gravity, etc, are much more complex and "systemic" we think.

But sure, there is lot of epistemological traps, pseudoscience, bullshit and honest dead ends in the process.

It's absolutely possible to argue persuasively for high level laws without having a full reductionist mechanics. For example, Darwin's arguments for evolution by natural selection were strong even though the physical/chemical basis of heritability was totally unknown in his time. He didn't even know Mendel's laws. Fisher also developed his models of evolutionary dynamics without knowledge of the underlying mechanics of heritability, and his models still stand. In fact, I'd argue that a big part of what makes a good scientific theorist is the ability to formulate and test high-level laws without complete knowledge of lower-level mechanics.
... "natural selection" IS the mechanics. The reason it's convincing is you can imagine what would arise, systematically, from imperfect reproduction under forces of selection, NOT because it's an attractive theory you saw in the tea leaves of the complexity of the world.
It's also falling that a historian would discredit an idea by referring to "phlogiston" which is only the go-to cliche for "haha ridiculous premodern scientific bad idea" just because the name sounds old-timey and obsolete.
In your view, what is the not-wrong essence of phlogiston theory?
That the energy output of a flame is regulated by the oxygen flux. Phlogition theory suggests a phlogiston flux that is just the oxygen flux with a sign reversed and consequently when they measured the mass of the phlogiston, they got a negative value.
A lack of understanding is like dirty glasses, everything blurs together and it becomes impossible to distinguish between right and wrong ideas.
I don't agree that the essence is not wrong, but I can imagine a decent argument for that position predicated on considering Phlogiston as chemical energy. Some substances can easily release energy through oxidation, others not so much.