The epistemological status of the ‘laws’ of physics can be usefully examined in terms of the interpersonal system of modality, in which modalisation is distinguished from modulation. Modalisation covers probability and usuality, whereas modulation covers obligation and inclination. Congruently, the ‘laws’ of physics are propositions — held with very high values of certainty — that describe phenomena in terms of very high values of modalisation: probabilities/usualities. If these probability/usuality descriptions are deemed to be laws in the sense that the universe obeys them, then such a construal is (interpersonally) metaphorical — and needs to be unpacked to avoid misunderstanding — since modalisation is reinterpreted (misinterpreted) as modulation: obligation.[1] A description of phenomena is re-presented as a prescription for phenomena; statements that describe are re-presented as commands that are obeyed.[2]
Mistaking this metaphor for a congruent rendering can lead to ideationally inconsistent claims about the epistemological status of the ‘laws’ of physics, two of which can be identified here. As already discussed, one stance is to equate (mathematically ‘=’) the ‘laws’ of physics with the categorisable phenomena being described. The model and the modelled are one and the same, with one copy “out there in the observable world” and another copy “in the heads of physicists”. This leads to such confusions as being amazed that humans can understand the universe[3] — whereas understanding, modelling in the pursuit of consistency, is a process that humans, as animals with neurological recognition systems, undergo.
The other ideationally inconsistent stance proceeds from the view that ‘the physical laws govern the universe’. The view here is that the (abstract) physical laws, as governors, transcend the (material) universe they govern.[4] This can result in the physical laws being located in an idealised and unobservable — and so: unscientific — Platonic realm, and, since the physical laws are both outside the universe and in control of it, it can also entail a sort of deification of the laws, since they both occupy the position, and perform the functions, ancestrally ascribed to gods.[5]
Footnotes:
[1] Note that (interpersonal) obligatory modulation (x must y) corresponds to (experientially) a passive causative process (x is required to y). See Halliday & Matthiessen (2004: 523).
[2] This metaphor also pervades mathematics, the major tool for physics, where ‘consistently describable by numbers’ is interpreted as ‘governed by numbers’. For example, in his The Ascent Of Man, Bronowski says:
Pythagoras proved that the world of sound is governed by exact numbers, and he went on to prove that the same thing is true of the world of vision.
[3] This applies to mathematics as much as physics. For example, Ruelle (1993: 161):
We do not understand why the world of mathematical truth is accessible to us.
[4] Similarly, before General Relativity, it was also thought that time and space transcend the universe, in the sense that the universe is “in” space and time, rather than space-time being the dimensions of the universe.
[5] Einstein’s ‘God (the laws of physics) does not play dice’ criticism of quantum mechanics.