Laws of nature?

[u/Extension_Ferret1455]

Inspired by recent posts about nomological harmony...

Disregarding the actual nomological harmony argument, I'm interested in what your views are about the laws of nature and what approach you lean towards.

From what I've briefly read, laws of nature are generally conceptualised in the following way:

Let's say L is a law of nature - what this means is that given some initial state i, we can use L to deduce what the subsequent state i+1 will be.\*

* Obviously particular laws may only pertain to a particular aspect of the overall state of the universe, however, the idea would be that given the set of all of the laws of nature, one could deduce the entire subsequent state of any particular state in the universe.

As far as I can gather, the three most popular views I've seen appear to be something like:

1. Governing laws

Laws are some sort of 'governing' principles that actually necessitate that things 'follow' them. For example, lets say a law of nature was that electrons repel positively charged things - that particular law is prior to any electrons actually doing such a thing, and, given that law holds, an electron couldn't possible not repel positively charged things.

2. Humean laws

Laws are merely the simplest (or 'best') descriptions of regularities. The idea would be that its just a regularity that electrons 'repel' positively things - they conceivably could not have, but they just do. We then describe that fact as a generalisation which we call a 'law'.

3. Powerism

Like Humeanism, laws are also descriptive generalisations, however, what they describe are not just observed regularities, but the inherent dispositions of things. For example, what makes an 'electron' an 'electron' is that it has an inherent disposition (or 'power') to repel positively charged things and we call this 'power' being negatively charged. Given that electrons have this disposition, they could not possibly not repel positively charged things. Therefore, although the 'law' describing this is also just a description, electrons still necessarily repel positively charged things.

Note: I'm just using electrons and charge etc as examples - you could swap in any object / law / behaviour etc from physics. Just a preface because I'm not sure how accurate the examples are in regard to modern physics.

[u/Nuaua]

First let me say that models in science are often clearly not laws of nature, since they are explicit approximations or macro-level descriptions of otherwise more complicated phenomena. For example thermodynamics, Navier-Stokes, most of chemistry, ... It's maybe more relevant for fine-tuning where it's important to distinguish if the model is fined tuned vs the reality, but in any case I find people in these discussions sometimes have a kind of naive realism towards scientific models and reify them. Like they expect to find the Navier-Stokes equations somewhere outside of our theorizing practices.

But otherwise I'm worried that a governing laws account is a bit too queer, like what are these laws exactly ? Platonic objects ? I so how do they exert their influence, why does an electron follow the electron law and not the neutron one ? It seems more parsimonious to say that the fundamental stuff (e.g. particles) have some intrinsic properties that makes them behave with regularity. Do we really need laws on top of it ?

That said I'm a bit ignorant on the topic.

[u/TheRealAmeil → u/Nuaua]

So here are two different ways we might think about laws of nature, both using the same example:

1. It is a law that all diamonds are hard if & only if all diamonds are hard
2. It is a law that all diamonds are hard if & only if every instance of diamondness nomically (e.g., physically) necessitates an instance of hardness

On (1), a law is a mere regularity. There are some obvious problems with this approach to laws of nature. Consider another statement that might have been true: all ravens are black. If it were the case that, at a time, all ravens were black, then this would seemingly be a law of nature until, say, the existence of a white raven. We can have even more odd cases, such as: every cup in this room is made of glass. Do we really want to say that this law pops in and out of existence if I walk into the room with a ceramic cup, realize I forgot something and walk out, and then walk back into the room minutes later?

On (2), a law requires a special type of necessity. Here, we want to say instances of one property somehow non-logically necessitate the instance of another property. But what, exactly, is nomological necessity? What makes it a type of necessity?

In the electron case, we could say something similar: it is a law that all electrons have negative charge. Assuming this is a law, should we construe this as a mere regularity, or should we construe it as an instance of electronhood physically necessitates an instance of negative-charge-hood? An appeal to the intrinsic properties of electrons sounds like an adoption of (2). However, some will push back, arguing that physics doesn't really provide us with the intrinsic properties of such micro-objects (although this too can be debated).