How the Laws of Physics Lie

by Nancy Cartwright

In this sequence of philosophical essays about natural science, the author argues that fundamental explanatory laws, the deepest and most admired successes of modern physics, do not in fact describe regularities that exist in nature. Cartwright draws from many real-life examples to propound a novel distinction: that theoretical entities, and the complex and localized laws that describe them, can be interpreted realistically, but the simple unifying laws of basic theory cannot.

Genres: Philosophy, Science, Physics, Nonfiction

230 pages, Paperback

First published June 9, 1983

Reviews

[Alex Lee · Rating 5 out of 5]

This is an amazing book. Although Cartwright touches on the topic of scientific laws (theories) and the limit of their applicability she approaches this not with Karl Popper in mind but J.S. Mill. So her statements have an applicability beyond science that touches on logic, mathematics and reasoning itself. She presents a weaker view challenging the undecidability of quantum mechanics as a mathematical artifect (something David Bohm and somewhat like Karen Barad as well) but her basic questioning rips through the "natural" assumptions which scientists and the public often adopt. By doing so she allows a greater critical perspective on how to "do" science. This may be frightening for people because in as much as we know there is also much we do not know; in fact the two are proportional to one another as the more knowledge cuts and defines the more it carves out negative areas of unknowning. The basic mix up she starts with is pretty profound: the difference between causation and explanation.

Even though the writing is dense it remains very approachable. After the first chapter I was definitely hooked; this is a book that offers rich treasures to anyone who wishes to actually critically look at our world and how we have a choice in how we arrange the information we get.

[Frederick · Rating 4 out of 5]

Philosopher of Science Cartwright argues some very interesting points in this series of essays. Cartwright does not swallow the idea of general laws that apply to everything and are true in most cases. She sees the universe as a little less ordered than that and, in fact, insists that when put to the test many of the so-called laws of Physics cannot be proven true. Most laws are simply false, she says. She doesn't find a huge problem in this, though, as a law's ability to explain why something happens isn't necessarily tied to any sort of reality, if I am understanding her correctly. To my untrained mind this is an absurd proposition and perhaps one of the problems of modern science. They propose unproveable and unseeable theoretical entities to explain visible effects and create laws governing their existence and behavior, laws that often don't work for fantasy entities that no one can prove the existence of. It is very strange but very interesting.

[0:50 · Rating 2 out of 5]

Some good examples of how much of a patchwork even the most venerated hard science can get but largely from a "this is how it is" perspective. The problem of causality, at first displayed as central to the book, remains unanswered, normalized under the term "causally relevant factors". Yet elsewhere, as in the in itself interesting treatment of probability distributions, the notion is thoroughly problematized. Causal chains are not accessible this way. As a child I used to try to wake my mother up by putting her glasses on her head while she was asleep because that's how I'd seen her awake. It worked every time but at the same time its specific nature did not explain her waking up, as any stimulus would have sufficed. But the stimulus need not be even an object but just an atmospheric or electric shock, or further, some type of stimulation of the brain to provoke an impulse that would cause the awakening. But then it could also bypass the impulse altogether and the waking up could theoretically be a simple arrangement of her brain and other contents to a position corresponding to "awake". Further, one could induce somehow an image to her dreams that would, by proxy, cause in her an awakening. What, then, is "causally relevant"? It seems causes only make sense from the perspective of laws and presuppose them: there has to be something that "must" happen for causal inference to take place. Unless you presume the conservatism of sticking with my original primitive inference, just calling things "causally relevant" has no meaning from the perspective of advancement of knowledge where the horizon is not limited.

Conversely, is the cause of her waking up the state of my brain at the moment of decision or some (arbitrary) sequence of states("movement", "impulse") before it? The conceptual history would span the entire universe. But if I stick with the situation at hand, I'm always going to put the glasses on thinking that yes, this is "the" thing to do: and so I would be stuck in a horrible and embarrassing illusion of confidence. Like, Hume's problem wasn't just some sophistical bullshit. It seems so easy to make that step from the outside, as if the wider reality was in my mind already: but the whole point is that it wasn't and it's not obvious that it is unless you think also about what is possible instead of just observing the situation and applying a solution that makes sense of the situation.

The discussion on quantum mechanics also didn't date very well, as it tries to hand-wave away the measurement problem and the logical/metaphysical questions surrounding superposition. This might work with the simple double slit set-up but the later experiments based on Wheeler's delayed choice ideas involving entangled photons present a far more challenging picture.

[Jeff Vandegrift]

In 1974 my MIT Physics roommate, "a genius amongst MIT geniuses", asked me "do you think advances in physics result in us approaching the truth?". I mechanically answered "yes" and then IMMEDIATELY regretted having said so. I realized, e.g. in 1900, I would have said "Newtonian Physics is the truth", but a few decades later I would have said "nevermind, Einsteinian Physics is the truth". Either the physics keeps changing and we catch up (unlikely) or we may possibly be on an infinite path of "refinement" in the so called "laws of physics". Maybe we're just modeling better than ever and will continue to model and predict even better.

My contention is two fold: 1) there is no evidence that we've measured everything with enough precision to declare a complete and final validation of today's best "laws of physics", and 2) even if we have, it is impossible to prove that the equations we attribute to our observations are in fact the actual rules that drove the universe to produce those observations.

One view is that Math and Physics are simply Darwinism at work. What works survives and what doesn't work is completely forgotten. If 1+1=3 worked in the world we'd have kept it, regardless of anyone's theory to the contrary. From my observations 1+1=3 doesn't help me in any way so I don't even think of applying it (with the exception of using it for this argument)

Full disclosure... I have just started this book. I only know of it from Prof. Steve Gimbel's Great Courses Philosophy of Physics (paraphrased title, it's recent Prof. Gimbel). I will need to skip some of the details, I'm not of the math or physics caliber of the author.

[saml · Rating 4 out of 5]

it's a classic for a reason: it's very fun to read, lays out a whole new picture marvellously quickly, and works through actual physics voraciously. cartwright has all the iconoclastic fun of van fraassen or feyerabend whilst sounding dramatically more plausible. the picture is obviously underdeveloped here, and the final attempted dissolution of the measurement problem perhaps shouldn't convince any more. still, it's a book that gets you really excited about what philosophy of science could be

[Forked Radish]

It’s good to know that someone rejects the idiotic legalistic notion of natural cum scientific “laws”. When all laws that ever have existed, exist now, or ever will exist were created by humans, and maybe beavers (they were the first engineers, after all). 🦫

[B.D.N. · Rating 3 out of 5]

3.5

[Scott]

http://www.jstor.org/stable/4545199

[Boaz]

Discussions of explanation, nomological machines, ceteris paribus laws.