I will try to summarize what should be a general consensus (more or less). We would first have to define our terms: "law of nature" and "universal".
Two different types of "laws of nature"
There are two distinct things that are called laws of nature, that one tends to confuse, but:
- The first type is a human creation: it's expressed in symbols, diagrams, etc. It belongs to the field of mathematics, and when applied, it belongs to the field of physics and engineering.
- The second type is of a different order: it is postulated (in philosophy) that there exists some form of organization in the universe -- in the time of Newton it was conceived as a "clockwork" -- and that this organization follows a definite pattern.
Why are these two things distinct? Because science moved from pre-Newtonian to Newtonian mechanics, and then discovered other phenomena (e.g. electromagnetic), as well as relativistic and quantum mechanics, etc. And each time, the mathematical representation changed and it will change.
By contrast we assume that the philosophical law of nature -- of which the mathematical one is our best approximation -- is unchanged and exists independently of our understanding and, presumably, our very existence as humans (though there can exist philosophies that deny existence to the physical universe outside of human perception).
The assumption is that we are trying to approximate those laws with increasing accuracy.
What do we mean by universal?
I assume that by universal you mean:
Of, relating to, or affecting the entire universe: the universal laws of physics. (American Heritage)
The relation between universal and the universe as we understand it today is not obvious, since Webster's 1828 definition did not express things in this fashion:
- All; extending to or comprehending the whole number, quantity or space; as universal ruin; universal good; universal benevolence.
The universal cause acts not by partial, but by general laws.
In that case, it meant "applicable to everything", in a philosophical sense. By which it meant litterally everything. So let's call it (just for the sake of this here discussion) generalized universality.
The problem is, what people at the time of Newton conceived as universe (the sun and a few stars), progressively expanded into massive number of stars, a galaxy, other galaxies, clusters of galaxies, etc.
This expansion of our horizons was humourously summarized by Douglas Adamas (The Hitchhiker's Guide to the Galaxy) as:
Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.
In this early 21st century, it's even worse, because we incrasingly tend to make a distinction between this universe and other possible ones, with multiverses:
The collection of parallel universes that comprise all of reality in some quantum mechanical and cosmological theories. (American Heritage)
It stands to reason that there those universes exist in a different physical continuum (otherwise it would be the same universe). But it is also speculated that laws of nature might be different in an other universe.
Hence we might be prudent and think, philosophically, of a restricted universality of natural laws (our universe).
About Newton's Laws
So Newton might have thought that the laws in the Principia Mathematica were universal.
- Today we might consider that Newton laws are universal in a restricted sense, because gravity seems to work in a uniform way throughout the universe (but who knows what those rules might be in another random universe).
- But there is a caveat that they are not universal even for this universe, because we know now that they break down in a variety of cases, particulalry when masses or speeds are very high -- which we know now is a problem for orbits close to the Sun, or when you want to calculate a position with GPS.
So without going into the depth of Ancient or early eighteenth century metaphysics, or the atheist-creationist slanging matches, the compromise in purely physical sciences is just that the question of ideas (theory of forms, etc.) or spirituality is not necessary to solutions of the problems of physical laws concerning chemistry, mechanics, astrophysics, etc.
Nevertheless I would say that yes, it is conceived that there is some kind of inner structure of the observable universe, which then leaves anyone the freedom of metaphysical interpretation.
Henri Poincaré noted (in the preface of Science and Hypothesis, 1905) that:
The method of the physical sciences is based upon the induction which leads us to expect the recurrence of a phenomenon when the circumstances which give rise to it are repeated.
It's an induction (trying to go from the particular to the general) and expecting a recurrence (so that same conditions would lead to same happening). It is implicit that people who work in physical sciences assume that there is that kind of recurrence, which is (hypothetically, but assumed certain for all practical purposes) universal.
The bottom line is that there is, within the confines of our science, no mathematical representation of natural law that is universal. But we like to assume, philosophically and because it is practical for everyday purposes, that there is a system of natural law in the cosmos.
The problem of the expansion of our understanding
The concept of multiverses postulates that different conditions exist in different universes. Of course if one was able to make a consistent "theory of everything" that would describe whatever existed in any universe then would assume some sort of generalized universality... but that would a giant leap into speculation (or hypothesis).
And supposing that such a theory of multiverses could exist and considering the continuous expansion of our sensory and intellectual horizons, who knows that it would not break down once again in some corner?
We could find various quotes about this problem, e.g. Richard Feynman (1918-1988) [emphasis added]:
- Are you looking for the ultimate laws of physics?"
- No, I'm not. I'm just looking to find out more about the world and if it turns out there is a simple ultimate law which explains everything, so be it; that would be very nice to discover. If it turns out it's like an onion with millions of layers and we're just sick and tired of looking at the layers, then that's the way it is. ... My interest in science is to simply find out more about the world.”
I guess that this "modesty of hypotheses" is a predominant applied philosophy in the scientific community today.