A lot of ink has been splashed around trying to construct watertight formal definitions of laws - and here, of course, I am talking about scientific laws or laws of nature - not the legal kind. But, if you think about it from another angle, such laws are very mysterious in all sorts of ways - ontologically, metaphysically, and so on.
Try considering, for example, how a law of this kind might be created or in some other way come into existence. Imagine trying to set about the task of bringing it about that there are such laws. Where would you start?
Here's one thought: laws cannot precede objects (i.e they cannot be created out of nothing). But then, if there have to be objects (using that notion in the widest sense), wouldn't any laws relating to them be derivative - that is: dependent on their nature? So could we not deduce some sort of essentialism from the the very existence of laws? Laws can only exist if the relevant objects have certain definite properties?
The underlying thought here is if ontology takes priority, then laws are descriptive - after the fact entities, if you like. Can we conceive of a world in which there are just laws, and nothing else?
In such a world, if objects come into existence, they will be bound by these laws. But, what does the binding?
Imagine you have god-like powers. How would you create laws starting from scratch? Isn't it misleading to think of laws as some sort of metaphysical glue that can make sure that objects do what they are supposed to do?
Perhaps it is a mistake to think of laws as being separate from entities. How, in an empty world, do laws get going? If objects emerge in such a world, wouldn't their law-like behavior have to be a function of their very nature rather than a result of conformity to pre-existing laws?