Many people view so-called discovery of natural laws as one of the determining factors behind our rapid advancement in understanding the natural world. But can the laws deliver the burden we place upon them?
Først publisert hos London Institute of Arts and Ideas i juni 2023.
In “The Grand Design”, Stephen Hawking and Leonard Mlodinow put forward the ambitious claim that the history of science can be summarized as “the long process of replacing the notion of the reign of gods with the concept of a universe that is governed by laws of nature[1].”
What is meant by such a “law of nature”? Views widely differ, but some views of prominent contemporary physicists are worth mentioning. Sean Carroll proposes that “the way physics is known to work these days is in terms of patterns, unbreakable rules, laws of nature[2]” while Hawking & Mlodinow state a natural law is “a rule that is based upon an observed regularity and provides predictions that go beyond the immediate situations upon which it is based[3].”
A very modern illusion
Renaming a “law” into a “rule”, a seemingly abstract concept somehow also responsible for the prescriptive capacity to “govern the universe”, is already a spectacular feat. Ludwig Wittgenstein, on his part, would have thought this picture to betray these modern physicists, hardly an upgrade on the older faiths. Wittgenstein argued:
“At the basis of the whole modern view of the world lies the illusion that the so-called laws of nature are the explanations of natural phenomena. So people stop short at natural laws as at something unassailable, as did the ancients at God and Fate. And they both are right and wrong. But the ancients were clearer, in so far as they recognized one clear conclusion, whereas in the modern system it should appear as though everything were explained[4].”
Of course, much hinges on what is meant by “explanations” by Wittgenstein above. If we’re satisfied with describing some abstract way to relate a specific phenomenon to more general ones, then we’re most likely fine. If we want more than that, as if we want to say something about the nature of the phenomena we’re investigating or the world’s intelligible character, we’re confronted with the surprising proposition that all throughout history, “a law of nature” has never explained anything like this. Observing “regularities” in nature, even cataloging them to the extent that we can characterize them with mathematical precision, hardly counts as “explaining” those patterns, rather than just restating them using different terminology.
How mathematics changed our view of nature
The innovation of coining nature in terms of mathematized “natural forces”, although a prerequisite to the acceleration of scientific progress, didn’t in itself represent a progress of reason. Neither was this way of framing these issues discovered as findings of empirical methods. The renowned philosopher of science, Alfred North Whitehead, thought them a fashionable shift, a result of an anti-rationalistic movement opposing “the rationalistic orgy of the Middle Ages”[5]. The movement was a sensible one and is one we owe our thanks to. However, it was never fought in the service of reason, and it was dependent on our ability to ignore the deeper issues.
The ancients and medievals were interested in discovering the inner workings of nature, as to what questions about the nature of causal powers and why nature operates in the manner it does. When we invoke the language of natural forces, this quest is not continued, but suspended. Far from explaining the natural world, it redefines the questions at hand. Discovering that the motion of natural objects conforms to systematical patterns that can be described by mathematical equations, which we might give names of “Gravity” or “Electromagnetism”, no more explains that motion or change or the nature of the entities involved, than does the insight that there are rules enclosing a game of chess, explain the nature of the chess game or why pieces are moving around the board in the first place.
Simply naming these patterns leaves untouched the issue as to the necessary prerequisites of those patterns. If we are to enjoy the luxury of maintaining explanatory power of how and why chess pieces move around the board, we have to invoke agency. In some sense, that could be true of everything from human cultures and moral behavior to the formation of hydrogen molecules and quantum particles as well. Without agency, everything grinds to a halt.
Locating causal powers
The dominating Aristotelian notion of natural causality, that was meticulously explaining causal powers by locating them in natural substances, maintained agency through a teleological hierarchy – an inherent directedness of all things towards ends. When pioneers of the modern sciences ignored formal-with-final causality as a natural source for agency, they needed to situate this somewhere else. That is why “Laws of nature” initially came to be invented as a wholly theological concept, describing divine decrees, requiring God as the primary efficient causal source of all natural, secondary causation, as formulated by the likes of a Bacon, Galilei, Boyle, Descartes or Newton. Indeed, Boyle writes in one of the key texts of the scientific revolution:
“[N]ature is not to be looked on, as a distinct or separate agent, but as a rule, or rather a system of rules, according to which these agents and the bodies they work on, are, by the great Author of things, determined to act and suffer[6].”
These natural philosophers still relied on the philosophical heritage of their predecessors of course. The remnants of Greek rationalism offered mathematics, a gift that these men of science could put to a much more practical vision than all history hitherto. And, says Whitehead, the rationality of the Greek philosopher could be improved by insisting upon the rationality of God and the personal energy of Jehovah[7].
Five theories about law
Unsurprisingly, relying on theology to make sense of natural laws will not satisfy most modern physicists or biologists, least of all Hawking or Carroll. Our puzzle remains to find any sustainable alternative. The problem of identifying the ontological status of natural laws is hardly unnoticed by philosophers of science. Philosopher Edward Feser, himself an Aristotelian, sketches five strategies to address it[8].
1. The theological view
A Descartes or a Newton saw natural laws as essentially divine commands. When Descartes started his project to reconceptualize nature according to the one field of study he knew could provide the most certain basis for knowledge, mathematics, the new quantitative conception of matter was passive and inert. Any causal agency would have to come from the outside, with God imposing his will upon matter. The laws were universal and unbreakable because they reflected the rationality of the eternal creator of the entire universe.
Needless to say, this is not a very attractive view, even for a theist. With nature deprived of its independent causal powers, any sciences that sets out to investigate these are out of work. And with God being the only real agent, this view, taken to its logical conclusion, tends towards collapsing nature and God into one pantheist mesh.
2. The regularity view
This view gained traction when the likes of David Hume desired to strip down the weight of ontological commitments, stating that a law is simply a regular pattern that we happen to observe in nature. What is, is just what happens to be, and that’s it. It doesn’t exist because of anything, but it’s a mere brute fact. This might seem as a safer alternative to many, with a superficial appeal of epistemic humility.
At a deeper look, that might not be so. A devasting charge, as alluded to in the beginning of the article, is again that the regularity view doesn’t explain but simply redescribes. And that is per definition everything a regularity view could ever do. To use Feser’s example: “Suppose you say:
“Planets always move in elliptical orbits. I wonder what explains that?” Suppose I answer: “Kepler’s first law explains that.” You then ask: “Oh, how interesting. What is Kepler’s first law?” And I respond by telling you that Kepler’s first law states that planets always move in elliptical orbits. Obviously, we’ve gone around in a circle[9].”
Even if we were to call Kepler’s laws special instances of Newtonian or Einsteinian laws, the same accusation would apply to them. While the theological view would state that such elliptical orbits hold because God decreed it, that counts as an explanation, although perchance a weak one, the regularity view responds that it is just a matter of fact that all such orbits happen to be elliptical, which is much less than an explanation of the kind the natural sciences require, and even less capable of justifying the epistemically aggressive claims of Hawking and Carroll in the introduction.
3. The Platonic view
The demise of Platonism in contemporary philosophy might be prematurely stated. If Richard Rorty is right, what divides the Platonists from the anti-Platonists, is that the former thought it possible to represent truth in language and thought[10]. Platonism remains a popular view to justify our attempts to defend some sort of realism, including say, abstract objects, as 38,4% accepted or leaned towards Platonism in the most recent PhilPapers survey of philosophers [11].
Perhaps the properties referred to in scientific theories also have this kind of abstract existence of a Platonic variety? Even if so, the problem remains as to how natural laws can be prescriptive entities. Abstract objects are also inert, so a law of thermodynamics would be no more able to govern the events of nature than sets or prime numbers. Also, why should nature correspond with one set of natural laws, as opposed to others. If Platonism is true as an ontological foundation for laws, then there are abstract entities corresponding to all sorts of possible laws, both existing and non-existing.
4. The instrumentalist view
Instrumentalism is another view in the philosophy of science. As some believe that the theoretical entities posited by scientific theories are only convenient fictions useful for scientific purposes, that might hold to the causal structure of the world as well. Besides having the implication of threatening scientific realism altogether, there are many possible objections to instrumentalism.
One prominent candidate is Hilary Putnam’s “No miracles”-argument, stating that the predictive success of the sciences would literally be a miracle if these entities were mere fictions. Besides, if we grant the move of inserting “usefulness” as the decisive term for how we distinguish the convenience of our fictions, we have to ask the question: “Well, useful for what”? If there is a goal for scientific processes that can be designated as “useful”, or if talk of laws are only metaphors to attain this end, both this goal and the metaphors need to be in principle possible to cash out in other terms. It is doubtful if this is even possible, without invoking metaphysically laden terms like “truth” or “existence”, which undercuts much motivation to be an instrumentalist in the first place.
5. The Aristotelian view
Last, there is the alternative of looking back in history to what laws of nature supposedly replaced. For the Aristotelian, “laws of nature” is really “laws of the natures of things”. Rather than positing something outside of the natural entities that laws are supposedly “governing”, the resulting regularities are really just expressions of how things will behave given their inherent natures. This is a possible golden mean between relying on external agent for the prescriptive force of nature, such as God or Platonic forms, or giving up their explanatory power entirely, as with regularity or instrumentalism.
The radioactive decay of uranium is not determined externally, by laws or divine commands, but from active and passive causal powers found within the substance itself. That of course doesn’t end our rational investigations, but builds a possible bridge between the modern and the older sciences, as it’s only meant as the beginning of an explanation, to be continued by investigations of chemical and quantum substratum and so on.
It is also an excellent bulwark against reductionism, as top-down causation is made intelligible when natural substances can be sources of causal agency, without having to locate it a micro-level, where volcanos, avalanches, particle decays and human wills are all victim to the same indiscriminatory regime of determinative laws.
The way to go forward might be to go medieval.
[1] Hawking & Mlodinow, 2010, p. 17
[2] Carroll, 2014
[3] Hawking & Mlodinow, 2010, p. 27
[4] Wittgenstein, 1922, p. 87
[5] Whitehead, 1925, p. 16
[6] Boyle, 1686/1996, p. 106
[7] Whitehead, 1925
[8] Feser, 2014, p. 69-72; 2019, p. 177-190
[9] Feser, 2019, p. 183
[10] Rorty, 2001
[11] Bourget & Chalmers, 2020
References
Bourget, D & Chalmers, D. (2014). What Do Philosophers Believe? Philosophers on Philosophy: The PhilPapers 2020 Survey. Philosophers’ Imprint.
Boyle, R. (1686/1996) Free Enquiry into the Vulgarly Received Notion of Nature. Edited by Edward B. Davis and Michael Cyril William Hunter. Cambridge Texts in the History of Philosophy. Cambridge: Cambridge University Press.
Carroll, S. (2014, March). “God and Cosmology: The Existence of God in Light of Contemporary Cosmology”. New Orleans Baptist Theological Seminary.
https://www.reasonablefaith.org/media/debates/god-and-cosmology-the-existence-of-god-in-light-of-contemporary-cosmol
Feser, E. (2014). Scholastic Metaphysics: A Contemporary Introduction. Heusenstamm: Editiones Scholasticae.
Feser, E. (2019). Aristotle’s Revenge: The Metaphysical Foundations of Physical and Biological Science. Heusenstamm: Editiones Scholasticae.
Hawking, S & Mlodinow, L. (2010). The Grand Design. New York: Bantam Books.
Rorty, R. (1990). Objectivity, Relativism, and Truth. Philosophical Papers. Vol. 1. Cambridge.
Gerson, Lloyd P.; Gerson, Lloyd P.. Platonism and Naturalism (p. 398). Cornell University Press. Kindle Edition.
Whitehead, A. N. (1925). Science and the Modern World. New York: The Free Press.
Wittgenstein, L. (1922). Tractatus Logico-Philosophicus. Edinburgh: The Edinburgh Press.