On the start two notes:
- What is meant by a priori here, is not analytical a priori, where two concepts stand in some relation because of their content (where the concepts are nicely defined each on its own), but necessary relations which come from the impossibility of those notions to be taken as self-subsistent, but should be necessarily analyzed in some context (Hegelian sublation), in which these abstractions will show up as standing in necessary relation to other abstract notions which will appear in the context. More details further in the text…
- By physical laws here I mean actual physical laws of the world (if we assume there are such things), and not the physical laws which are product of science, and which are of course a posteriori and believed for empirical reasons (be it that we come to them by process of induction, abduction, falsification, or scientific revolutions to new incommensurable theories based on insight etc..)
So here are the reasons why I think it would make sense for those (actual) physical laws to be a priori…
1. Physical laws transcend time and space. This is a characteristic of a priori relations, like those of mathematics or logic. That if something can be put under the notion of two, it can be also put under notion of two ones, is true for anything, no matter when and where.
2. As much as the physical laws relate more and more notions, the self-subsistence of those notions is removed, and the richness of the world lost. Special relativity made identities between energy and mass, space and time, and general relativity between mass and space. Each of them was thought before as something independent, for which laws would provide just how it relates to the others in external manner. But now they disappear as something self-subsistent in this identity (this is connected also to the following point). The same happens in case of a priori relations – for example 1+1=2, where in their a priori relation both sides of the relation are not connected externally, but whatever is 2 is also 1+1.
3. There is also a reason why one might thing that they could be a priori. I’m not thinking of the Kantian approach (which I think has failed), but of an approach which would mix Hegelian holism and Einsteinian (Mach’s?) approach to what constitutes a measurement. Here is what I have in mind:
a) Some of the simple notions which appear in the physical laws, don’t make sense as self-subsistent notions. They make sense only in certain contexts (some richer notion), and those richer notions also implicitly show them in some specific relations to other abstractions from those contexts.
For example in the post on Hegelian dialectic method to which I pointed, I analyzed how left-right notions make sense only in context in which we have a “point of view”, which also has defined front and back, and top and bottom. All those abstractions – “top”/”bottom”, “back”/”front” then appear in some implicit a priori relations with the “left”/”right” notions within that context.
Or think about the notion of “movement”. It necessarily requires “something” (that will move), but also single something isn’t enough for movement – we need to imagine another something in relation to which this first something will move. So necessarily movement must be analyzed as moving-in-relation-to-each-other.
b) Measurement (or quantification) being what laws are about, the context in which those abstract notions (like “time”, “space”, “movement” etc…) appear, is necessarily extended to even more complex notion, in which those can show new a priori relations. To connect to the previous example of movement – measurement of space requires at least three things, A, B and C, so that a ratio can be made between the AB distance and BC distance. In same way measurement of time, requires two movements (or in general two changes), so a ratio can be made.
To summarize – some of the notions, as they don’t make sense as self-subsistent will necessarily be seen as abstraction in contexts (e.g movement as movement-relative-to-each-other, left/right as a fully oriented observer, etc…). Also by adding notion of quantity, this context will be extended necessarily to more complex notions – giving possibility for complex a priori relations between notions.
4. Symmetries appear to have central role in physical laws. Symmetries can easily appear in the necessary development from simple to more complex notions as described in the previous point.
5. It would provide a new way to address the mind-body problem. This will take some explanation too…
We could return to our naive-reality-kind being-in-the-world, in which the physical laws will then appear as necessary relations among different abstractions from it. And for any system, in which those abstractions are kept as more or less self-subsistent, the law will hold. The analogy can me made with a group of things, which we start dividing them into smaller groups through some procedure. As long as the things are self-subsistent (don’t disappear, multiply etc…) mathematical rules will hold between the numbers of things in each group and the starting number. However the nature of the concrete is not at least affected by those mathematical relations. For those mathematical relations to hold, it doesn’t matter what kind of things those are. In similar way, the concrete can be more than its physical abstractions, and while those physical abstractions will fall into necessary relations, still the concrete can be more than those, and is, as the naive-reality-world stands to the physical abstractions, in a subject/predicate relation. There would be no need of doubling to two worlds – world of mind and world of physics, the being-in-the-world contains everything which is usually taken as problematic for explaining through physical world (qualia, intentionality, etc…), and the physical world is seen as a predicate of this being-in-the-world. (For sure there would be separate metaphysical issues even if the physical laws turn to be a priori)
6. If we believe that there is a reason why the laws are such as they are, there is no better reason than them being a priori. (Any other reason will require new reason, or we would have to assume lack of it).