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by YeGoblynQueenne 1416 days ago
OK, thanks for clarifying. I feel that your description of neural nets' inner workings is a bit idealised and I'm not convinced that we have seen any evidence that they are as powerful in representing real-world phenomena as you suggest. But that's a big discussion so let's leave this aside for a moment.

I can agree that a neural net can learn a model that can predict the behaviour of a system, to some extent, within some margin of error.

That's not enough for me to see neural net models as (scientific) "laws". For the sake of having a common definition of what a scientific law is, I'm going with what wikipedia describes as a scientific law: a statement that describes or predicts some set of natural phenomena, according to some observations (paraphrasing from: https://en.wikipedia.org/wiki/Scientific_law). Sorry for not introducing this definition earlier on. If you disagree with it, then that's my bad for not estabilishing common terminology beforhand.

In that sense, neural net models are not scientific laws because, while they can predict (but not describe) they are not "statements". Rather they are systems. They have behaviour and their behaviour may match that of some target system, like the weather say. But like a simulation of the economy, or an armillary sphere are not, themselves "laws", even though they are possibly based on "laws", a neural net's model can't be said to be a "law", even if it's based on observations and even if it has an internal structure that makes its behaviour consistent with some (known or unknown) law.

There is also the matter of usability: neural net models are, as we know, "black boxes" that can't be inspected or queried, except by asking them to analyse some data. While useful, that's not a "law", because it does not help us understand the systems they model. If this sounds like a semantic quibble, it isn't. To me anyway it doesn't make sense to base scientific knowledge on a bunch of inscrutable black boxes. Scientific laws and scientific theories are not black boxes.

As an aside, neural nets fall short of what Donald Michie (father of AI in the UK) called "ultra-strong machine learning" [1]. That's the property fo a machine learning system that improves not only its own performance, but that of its user, also. Current techniques aren't even close to that.

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[1] Machine Learning: the next five years, Donald Michie, 1988

https://dl.acm.org/doi/10.5555/3108771.3108781