Friday, August 12, 2016

The Unbearable Lightness of Philosophy

Philosophy isn’t useful for practicing physicists. On that, I am with Steven Weinberg and Lawrence Krauss who have expressed similar opinions. But I think it’s an unfortunate situation because physicists – especially those who work on the foundations of physics – could need help from philosophers.

Massimo Pigliucci, a Prof for Philosophy at CUNY-City College, has ingeniously addressed physicists’ complaints about the uselessness of philosophy by declaring that “the business of philosophy is not to advance science.” Philosophy, hence, isn’t just useless, but it’s useless on purpose. I applaud. At least that means it has a purpose.

But I shouldn’t let Massimo Pigliucci speak for his whole discipline.

I’ve been told for what physics is concerned there are presently three good philosophers roaming Earth: David Albert, Jeremy Butterfield, and Tim Maudlin. It won’t surprise you to hear that I have some issues to pick with each of these gentlemen, but mostly they seem reasonable indeed. I would even like to nominate a fourth Good Philosopher, Steven Weinstein from UoW, with whom even I haven’t yet managed to disagree.

The good Maudlin, for example, had an excellent essay last year on PBS NOVA, in which he argued that “Physics needs Philosophy.” I really liked his argument until he wrote that “Philosophers obsess over subtle ambiguities of language,” which pretty much sums up all that physicists hate about philosophy.

If you want to know “what follows from what,” as Maudlin writes, you have to convert language into mathematics and thereby remove the ambiguities. Unfortunately, philosophers never seem to take that step, hence physicists’ complaints that it’s just words. Or, as Arthur Koestler put it, “the systematic abuse of a terminology specially invented for that purpose.”

Maybe, I admit, it shouldn’t be the philosophers’ job to spell out how to remove the ambiguities in language. Maybe that should already be the job of physicists. But regardless of whom you want to assign the task of reaching across the line, presently little crosses it. Few practicing physicists today care what philosophers do or think.

And as someone who has tried to write about topics on the intersection of both fields, I can report that this disciplinary segregation is meanwhile institutionalized: The physics journals won’t publish on the topic because it’s too much philosophy, and the philosophy journals won’t publish because it’s too much physics.

In a recent piece on Aeon, Pigliucci elaborates on the demarcation problem, how to tell science from pseudoscience. He seems to think this problem is what underlies some physicists’ worries about string theory and the multiverse, worries that were topic of a workshop that both he and I attended last year.

But he got it wrong. While I know lots of physicists critical of string theory for one reason or the other, none of them would go so far to declare it pseudoscience. No, the demarcation problem that physicists worry about isn’t that between science and pseudoscience. It’s that between science and philosophy. It is not without irony that Pigliucci in his essay conflates the two fields. Or maybe the purpose of his essay was an attempt to revive the “string wars,” in which case, wake me when it’s over.

To me, the part of philosophy that is relevant to physics is what I’d like to call “pre-science” – sharpening questions sufficiently so that they can eventually be addressed by scientific means. Maudlin in his above mentioned essay expressed a very similar point of view.

Philosophers in that area are necessarily ahead of scientists. But they also never get the credit for actually answering a question, because for that they’ll first have to hand it over to scientists. Like a psychologist, thus, the philosopher of physics succeeds by eventually making themselves superfluous. It seems a thankless job. There’s a reason I preferred studying physics instead.

Many of the “bad philosophers” are those who aren’t quick enough to notice that a question they are thinking about has been taken over by scientists. That this failure to notice can evidently persist, in some cases, for decades is another institutionalized problem that originates in the lack of communication between both fields.

Hence, I wish there were more philosophers willing to make it their business to advance science and to communicate across the boundaries. Maybe physicists would complain less that philosophy is useless if it wasn’t useless.


Matthew Rapaport said...

I hope you don't think all of philosophy is beholden to physics, or even science in general. There are a lot of subfield in philosophy most of which have no connection to science as such.

Then there are an awful lot of physicists and cosmologists writing philosophical books lately. Some respect principles of good philosophy (e.g. Unger/Smolin) while many do not. Out of politeness I will not mention names.

naivetheorist said...

"Many of the “bad philosophers” are those who aren’t quick enough to notice that a question they are thinking about has been taken over by scientists.". can you cite an example of such a question? it seems to me that the bad philosophers are not those whose questions has been 'taken over' by scientists but rather those who fail to recognize that their question was never a proper philosophical question in the first place. even in their own domain of of 'appropriate' philosophical questions, philosophers fail to employ the basic tool of logic. for example, the never-ending philosophical debate about the Humean guillotine (or Humean problem) - the Is-Ought dichotomy. It is obvious (to me) that one cannot go from a fact statement to a value statement. a statement such as "because of fact A, you ought to do B" is nonsensical and only makes sense if it is changed to "because of fact A, you ought to do B, IF you want to accomplish C" yet i have never known of a single philosopher who realizes this. Ultimately, the question is whether ANY question is an appropriate one for philosophy. i.e. What is philosophy useful for?

Unknown said...

"If you want to know “what follows from what,” as Maudlin writes, you have to convert language into mathematics and thereby remove the ambiguities. Unfortunately, philosophers never seem to take that step, hence physicists’ complaints that it’s just words."

Do you really think that mathematics is a language free of ambiguities? Not only analytical philosophy is not restricted to words, but mathematics and it's symbols are not at all unambiguous about their relations to the 'real' world. At the talk that you mentioned in the workshop last year you adressed very successfully philosophical problems with that state of things in physics today that are ignored by people like Weinberg exactly because they don't see how flawed can a concept be if it isn't connected to the natural reality in an unambiguous way. It is that relation, between language and existence that is explore and debated by philosophers.

Sabine Hossenfelder said...


No, I don't think all of philosophy is about science! But for this discussion that is the part of philosophy that is relevant.

Sabine Hossenfelder said...


Yes, unfortunately. Philosophers discussing the "hole problem" (which is no more), the "twin paradox" (dito), the "problem of infinities" in quantum field theory (not referring to non-renormalizable theories in particular, also a problem of the past), philosophers discussing the laws of nature without knowing what a Hamilton evolution is (mind blown), philosophers discussing emergence without knowing what effective field theory is (PLEASE!), philosophers taking about "gravity" without knowing what a manifold is (bury me now) and I once suffered through a talk by a philosopher who apparently invented some crude type of matrix model, not knowing that this is something physicists have been on for decades (and that his variant was obviously incapable of reproducing observations, for example because he assumed particle number is a conserved quantity). I have to add to this that after the talk even some other philosophers remarked that this was a quite nonsensical idea, so that might have been exceptionally bad. Then there was the philosopher who insisted that one can't introduce a preferred slicing in Minkowski space (which of course one can), and so on. Don't get me started on the supposed problem of "now" which in most of its incarnation is a problem merely of assuming the human brain is a point. Let me stop here. All very tiresome. No, I will not name names. If you do some digging you'll find plenty of this.

I would argue though, in contrast to what you say, that these all would once have been proper philosophical questions. They just are no more. A similar thing is happening right now with consciousness. It's becoming increasingly a research area of science, and it's about time philosophers wake up to that. Best,


naivetheorist said...


did you intentionally use humor in your comment about consciousness becoming a research area of science, and it's about time philosophers wake up to that? it's the old consciousness-wakefullness problem LOL.

best regards,


Sabine Hossenfelder said...


You write

"but mathematics and it's symbols are not at all unambiguous about their relations to the 'real' world"

You are conflating two different things. Yes, mathematics (done right) is unambiguous. But the relation of math to the real world is not itself math, it's part of what makes up a physical theory. That's why you have to test theories! You don't test whether the math works, you test whether you are using the right math.

Maudlin in his essay has some examples for such language ambiguities that have not yet been converted into math. A good example is "measurement" or "system" in quantum mechanics. I'd have another example, which is "quantum gravity." I normally start my lectures with explaining in which way I use the word, but I don't think everyone actually agrees on what is meant. Is emergent gravity, for example, actually quantum gravity? What if quantization is modified at high energies, not gravity? Are we still searching for quantum gravity then? Are we neglecting options because we're not careful enough in our terminology? Another example is "finetuning". There is a definition for this in the context of theory space for effective field theories, but that definition is incomplete (as I pointed out here). How can we fix this problem? Can we make that unambiguous? And what about finetuning in the cosmological context? Is this well-defined? So these are some examples for what I mean. (There actually have been philosophers on these questions, it just doesn't seem to have lead to much.)



Sabine Hossenfelder said...


Well, kind of. I don't know this particular problem, but it was an intended meta-joke. Maybe I should be somewhat more precise on that issue though. I think there are some aspects of consciousness that will remain inaccessible for science for a long time, possibly forever. It's just that there are some aspects for which that won't be the case. For example identity, memory, and free will, not to mention the question in how much humans differ in their perception of the world - these are all topics that science already has a lot to say about. Sure, nothing of this is settled yet. But it's something that philosophers can't ignore any more.

Uncle Al said...

Philosophy: Everything has value.
Quality Control: Discard defective products. Squandered investment, unending problems; irrelevant people wield power.
Quality Assurance: Defect detection stops the line. Find its origin, prevent recurrence; continuous improvement.

If we all love one another, everybody will die. Success exists. Two fat black holes merged within 0.2 seconds to equilibrium with no non-classical footnotes. Pseudoscience does not reduce to practice. Physics is not too big to fail. Support relevant successful people - or invent them.

Tommy Aquinas proved God exists. Baruch Spinoza proved God does not exist. Both were wrong.

Haelfix said...

The thing that bothers me about philosophers is the methods they use seem to have been a failure, historically speaking. For instance take the classic question about whether the world is deterministic or indeterministic.

Countless tomes were written reflecting upon the nature of what it even means to ask the question, and rereading's of Descartes thoughts on the matter! Vigorous debates were made, tenure was given.

Of course lost in all of this, is that the real answer could NEVER have been found this way. I don't care if you merged the intellect of Plato, Kant, Hume and Nietzsche thereby creating a sort of philosophical megamind. The real answer was so bizarre and unintuitive that you could have gone back and given them many hints, and they still would failed to get the right answer.

Quantum mechanics proved that pure thought alone, even of the Einstein physical variety, was not enough. To really answer the fundamental questions of the universe, the scientific method is therefore required.

KC Lee said...

"You don't test whether the math works, you test whether you are using the right math."

Well said. One point to keep in mind along that line is to remain "nimble" in the interpretation of equations. Look no further than Einstein's own interpretations of his field equations. In addition to the well-known example of the cosmological constant, Einstein flip-flopped repeatedly over whether black holes are really physical.

This nimbleness may come in handy when we face the most fundamental questions in the universe, where the likelihood of crossover fertilization between physics and philosophy could be at a maximum.

naivetheorist said...

what scientific method are you referring to: the Popperian falsifiability method or the David non-empirical method? the first is meaningful; the second isn't IMO

Quentin Ruyant said...

You complain that "bad" philosophers have a poor knowledge of science. I completely agree that it's "bad" (for philosophers of science of course, but even in other areas of philosophy, such as philosophy of mind). Now personally, most philosophers of science that I know have some degree in a scientific field, so perhaps it's a bit unfair and I never heard anyone defend that you couldn't choose a preferred foliation of space-time (that it is somehow arbitrary, or that cosmological time depends on a scale parameter, yes I've heard that). Anyway.
I would complain that most scientific have a poor knowledge of philosophy, and that might be bad too, particularly for foundational issues (I don't know of any big, fundamental theory that wasn't found by a philosophically minded scientist). The typical symptom, by my experience, is that they often take their naive philosophy for granted, and think that other positions are just stupid, and need not even be discussed. Some times that can even be turned into an argument against philosophy: philosophy is useless because they discuss X, while it's obvious that Y. Oh, ok. When as a philosopher you're aware of the huge literature on X, and of the subtle counterarguments against naive-Y, that can be a little upsetting, even when Y is your own position.
It seems that you have some philosophical knowledge, and you read philosophical essays, yet I can see this trend in your writing when you're talking about mathematics and ambiguity. These are very complex (and interesting) topics that (as another commentator note) has to see with problems of reference to the world, of conventional vs "synthetic" statements, of meaning, at the intersection of philosophy of mathematics, of language and of science. They are thoroughly discussed since a few centuries (including by scientists: Duhem and Poincaré are very good read on this). And the position that you just have to clarify meaning, turn this into mathematics and then do science is more or less what logical empiricist defended in the beginning of 20th century but today, it is generally recognised that it doesn't work. Now maybe your position is more subtle. Do not hesitate to give references.

Sabine Hossenfelder said...


No, I am not saying that you just "have to clarify meaning, turn this into mathematics, and then do science". I am saying that turning an idea into a mathematically formulated theory that can be put to test is what most theoretical physicists would think of as "useful" to advance their discipline. I am not even sure what you mean by "doing science", maybe you can elaborate?

My position on the relation between math and reality is laid out very clearly in this essay. Or at least I think it's laid out clearly. I believe I am moderate among the theoretical physicists in not believing that math is the ultimate languague of nature (just one that presently happens to be tremendously successful) and, indeed, I believe that math isn't even necessary to do science. It is, however, arguably useful. And that's the point this post was addressing. Best,


naivetheorist said...


Feynman expressed the same attitude as you about mathematics and science

"It always bothers me that according to the laws as we understand them today, it takes a computing machine an infinite number of logical operations to figure out what goes on in no matter how tiny a region of space, and no matter how tiny a region of time. How can all that be going on in that tiny space? Why should it take an infinite amount of logic to figure out what one tiny piece of space/time is going to do? So I have often made the hypothesis ultimately physics will not require a mathematical statement, that in the end the machinery will be revealed and the laws will turn out to be simple, like the chequer board with all its apparent complexities. But this is just speculation." (The Character of Physical Law - Ch. 2)

Wolfram (who was a friend of Feynman and was recommended by Feynman for the MacArthur 'genius' prize which he received has the same view, but even more strongly. it's too bad that he has offended the sensibilities of so many scientists by his dismissive attitude and his ego that they dismiss him (incorrectly) as a crackpot who just makes software.

Paul Hayes said...

Oh dear! IIRC, at least two of those three 'good philosophers roaming Earth' are members of the Church of Psiontology. One is even a Bohmian. That is damning. ;-)

Elias Zuniga said...

If “the business of philosophy is not to advance science," from how does that follow that philosophy is useless (to science)? Would the author or its readers consider the author's post to be a philosophical essay (one that argues for the uselessness of philosophy)?

KC Lee said...

"... in not believing that math is the ultimate languague of nature (just one that presently happens to be tremendously successful) ..."

Well said again.

Math is a language. The link by Magnusdottir you provided has this brief passage: "Pragmatic Physicists thinks of his ancestor, Pragmatic Neanderthal. She climbed to the top of the
fire mountain and scanned the land to her feet. “Why is the human eye so effective at perceiving the
all-there-is?” she mumbled to herself. “It is not,” said the time-traveler who just appeared behind her,
“It is due to natural selection that the surviving species are likely to be good at perceiving what is
relevant to their survival. You do not in fact perceive most of the all-there-is.” He was in the middle of
explaining galactic rotation curves when she hit him over the head and sacrificed him to the Fire God.
How effective is your math at describing her behavior?"

The distinction between math and reality is well worth being kept in mind. That way one runs less risk in over-valuating math vs. the other avenue seeking the same reality: philosophy.

Quentin Ruyant said...

Thank you for the reference. By "doing science" I meant (in that context) doing experiments.

If math is useful, but not the only language at our disposal, then probably philosophy could be useful in other ways, no? Anyway as Piglucci says, philosophy is an academic discipline that can be useful for its own sake (just as science is useful for its own sake, not only for technical applications). It doesn't have to be useful to science to be of interest. Sincerly I find this debate on usefulness a bit boring: why not assume that a whole academic field such as philosophy must be of interest, if so many smart people engage in it?

I can see that you're inclined toward philosophical questions, as you wrote a whole essay on the relation between math and reality. Is this question useful to the advance of science? I don't think so. But it doesn't have to be to be interesting.
Now regarding this essay, the fact that there is no reference to the *huge* philosophical litterature on the subject is rather telling. And indeed it's quite similar in spirit to the logical empiricism, or for a more recent view, to van Fraassen's constructive empiricism (except, of course, that their positions was much more detailed, formalised and documented). I'd have a few comments on it but I don't know if it's appropriate to post them here as it's no more about this blog post.

Arun said...

naivetheorist: Regarding the "Is-Ought dichotomy", I believe it is intelligible when there is a background assumption that God made all that Is, with a Plan that determined the "ought".

TheBigHenry said...

Uncle Al,

"Tommy Aquinas proved God exists. Baruch Spinoza proved God does not exist. Both were wrong."

To which I reply, "They can't both be wrong."

To which Sholem Aleichem replies (to me), "You're also wrong!" :)

Jim said...

"The value of philosophy is, in fact, to be sought largely in its very uncertainty. The man who has no tincture of philosophy goes through life imprisoned in the prejudices derived from common sense, from the habitual beliefs of his age or his nation, and from convictions which have grown up in his mind without the co-operation or consent of his deliberate reason. To such a man the world tends to become definite, finite, obvious; common objects rouse no questions, and unfamiliar possibilities are contemptuously rejected. As soon as we begin to philosophize, on the contrary, we find, as we saw in our opening chapters, that even the most everyday things lead to problems to which only very incomplete answers can be given. Philosophy, though unable to tell us with certainty what is the true answer to the doubts which it raises, is able to suggest many possibilities which enlarge our thoughts and free them from the tyranny of custom. Thus, while diminishing our feeling of certainty as to what things are, it greatly increases our knowledge as to what they may be; it removes the somewhat arrogant dogmatism of those who have never travelled into the region of liberating doubt, and it keeps alive our sense of wonder by showing familiar things in an unfamiliar aspect."

Bertrand Russell, The Problems of Philosophy (1912)

dlazerka said...

Hi Sabine,
Isn't superdeterminism disfavored by physicists for purely philosophical reasons? said...

I Am You: The Metaphysical Foundations for Global Ethics

Daniel Kolak

"The central thesis of I Am You — that we are all the same person — is apt to strike many readers as obviously false or even absurd. How could you be me and Hitler and Gandhi and Jesus and Buddha and Greta Garbo and everybody else in the past, present and future? In this book I explain how this is possible. Moreover, I show that this is the best explanation of who we are for a variety of reasons, not the least of which is that it provides the metaphysical foundations for global ethics."

piein skee said...

Feynman was a great genius who perceived the strengths and also the frailties of science, and his insights into the nature of science, and the relation of science to philosophy, were way beyond mere opining. He wasn't scornful of philosophy at all in general in human affairs, but he did see the threat philosophy posed, when on scientific turf.

The counter-argument of philosophers is that Feynman was himself a great philosopher of science. And he was. He was almost without doubt the greatest philosopher of science of all time. He was a great philosopher.
Philosophy make Feynman a centre-piece exhibit in their bid for legitimacy on scientific turf.

But Feynman was not a philosopher of science. He was a scientist of philosophy and a student of the nature of science, itself. Many claim scholarship there but only a few authentically were, and Feynman was one and the best of them for sure.

This stuff is scattered all across Feynman's body-of-work so referencing would be hard even for a scholar - which I am not - of Feynman to do. However, most of it can be found in his 'Character of Physical Law' lectures, and most within those lectures can be found in the final lecture in the series 'finding new laws'. And most within THAT can be found in the summing up.

I've turned myself onto watching it now, so I can let you have my google :o)

Peter Donnelly said...

One thing at least some philosophers seem to be extremely good it is identifying unclear and poorly framed language.

This is something scientists are often quite weak at, and it becomes very important when one gets close to the physics frontiers, for example questions around reality and causality.

JimV said...

The introductory Philosophy course at my university was very popular, at least among my friends who took it. It probably stretched people's minds, but as far as learning to think, it seemed to me that computer, math, and science courses do just as good a job, and probably better.

I think it is time that an introductory computer-programming course became a standard part of the curriculum for what we call "high school" in the USA. Trying to program a task with a computer language rapidly teaches the principles of logic, including the principle that there may be alternatives that one forgot to allow for. The computer is a good teacher because it provides empirical confirmation that a complicated set of logic does or does not work.

Also, certain philosophers who seem to regard the ability to make decisions and develop strategies as supernatural could learn some of the many such things that computer programs can do. Of course, some will argue that it takes a biological intelligence to write the programs, but it seems to me any good philosopher should see the flaw in that reasoning.

However, when I am about to become too critical of philosophers, I try to remember Sturgeon's Law, which suggests that there may be as many or more bad scientists as good scientists, so it is not fair to expect better of philosophers. Still, if I had to chose between "scientism" and "philosophism" I would chose "scientism" every time. said...

I think philosophy can also be useful post-science in examining the values and application of what science discovers.

And perhaps it has some value in-science just as an alternate way of thinking about things. Sometimes a different point of view reveals what was hidden.

Sabine Hossenfelder said...


Yes. And I blame Maudlin for this...

APDunbrack said...

TheBigHenry: I think his statement that they were wrong refers to the fact that they believed they had proved their point, not that they were correct. One cannot say that one of two arguments is correct, even if the conclusion is binary.

naivetheorist said...


i have no interest in engaging in any discussion involving God (and this would not be the appropriate place for such a discussion), save to repeat an well-known story:"

According to history (or so the story goes)

"Laplace presented his definitive work on the properties of the solar system to Napoleon. Napoleon, liking to embarrass people, asked Laplace if it was true that there was no mention of the solar system’s Creator (ie God) in his opus magus. Laplace, on this occasion at least, was not obsequious and replied, “I had no need of that hypothesis.” "

Quentin Ruyant said...

This is getting ridiculous. Philosophers are useless and not read by physicist, but when a majority of physicists disagree with you on a metaphysical point, you blame a philosopher...

Superdeterminism is not adopted for some reasons. Maudlin attempted to cash them out in the form of precise arguments that can be discussed. That's great and useful even if you disagree. If you don't agree, then go do a philosophy PhD on superdeterminism and QM interpretation then publish an article at the end of your research, but don't blame Maudlin for doing his job.

Quentin Ruyant said...

@jimV scientism is a philosophy

Sabine Hossenfelder said...


I wasn't serious when I said I blame Maudlin for the unpopularity of superdeterminism, sorry if that wasn't clear. I think it's a cognitive bias, as I've expressed elsewhere. I have published articles on superdeterminism, thanks for the suggestion. I might even write another one on it.

Ari said...

Off-topic: just read your article about consultation on There are actually self-taught physicists who aren't crackpots. Here's one example:

That's probably extremely hard. I don't know if he worked with/in an institution though.

I wanted to post on topic but I can't find one article.

Quentin Ruyant said...

Do you address Maudlin's concern that superdeterminism would undercut scientific method? Can we really be confident in scientific results without this "cognitive bias"? I'd except that a response to Maudlin explains why this is the case in much details (and what our commitments toward our theories should be in consequence. I suspect it would be lowered to predictive success only, thus it would be a brand of anti-realism: that should be made explicit). Now I don't know the philosophical standards in physics publishing.

Arun said...

Naive theorist, the point is, leave aside philosophy, the 19th century physicists' obsession with the luminiferous aether is not intelligible unless you understand their assumptions. So it is with "is-ought" problems.

Sabine Hossenfelder said...


You mean in my previous papers? No, because I've only become aware of this recently. I'll address this in my next paper (or at least try to).

ezydoesit said...

I suggest you guys check out Fritjof Capra and his book "THE TAO OF PHYSICS".

Kris Krogh said...

Hi Sabine,

I'm with you on philosopher Steven Weinsten. He points out what I think is a significant, but neglected shortcoming of general relativity here:

I had assumed he was a physicist.

Also, let's not forget Grete Hermann, who quickly pointed out a fatal mistake in John von Neumann's "proof" of the impossibility of hidden variables in quantum mechanics. (But was nevertheless ignored by the physics community for decades, until John Bell rediscovered her.)

Best wishes, Kris

Harrison said...

As Nassim Taleb has pointed out, "...mathematicians think in (well precisely defined and mapped) objects, philosophers in concepts, jurists in constructs, logicians in operators (...), and idiots in words."

You won't find the real philosophers anywhere near the modern academy! They remain in the mountaintops, in the true Nietzschean sense. Wittgenstein was an utter regression, as well as the closest unfortunate alignment with an apparently term-dismissive physics to date. Of course he set up shop much of his life in the "academy." Frankly, real philosophy has avoided being sucked into the service of the computer-marrowed zeitgeist and is often in the business of doing quite the opposite of 'advancing' it.

Suggested reading: Maya Deren's Anagram of Ideas on Art, Form, & Film


Uncle Al said...

@TheBigHenry, APDunbrack Self-referential epistemologies are empirically unconstrained. Philosophy and mathematics validate their postulates. Science looks.

To 1 part in 20 trillion relative, no measurable property of mass violates the Equivalence Principle (EP) - classical, quantum mechanical, relativistic, gravitational (strong EP). I say "baryogenesis demands opposite shoes falsify the EP external to physics." Theoretically wrong? Absolutely. Empirically true? LOOK.

As for god...start with a definition. giggle

Steve Agnew said...

Thanks for the Maudlin PBS essay link. I had not seen that yet.

I generally agree with that philosophy and science are complementary, but I tend to use different words.

Some science people presume that all matter and action in the universe are ultimately measurable and therefore understandable. However, that is not true in the universe that we are in. While there are many things about the universe that we do not yet know but can eventually know, there are simply also things about the universe that we can never know.

Philosophy has the role of not only dealing with things that science does not yet understand but eventually can, philosophy also deals with things that science can never understand. For example, why is the universe the way that it is? There is no answer and science must simply believe in the universe that we are in just like everyone else.

Once someone starts believing in matter and action by about the age of two, they can begin to make sense out of the world. There are a certain number of beliefs that we need to make sense world and science calls those beliefs axioms. Philosophy calls them ontology...go figure.

Science predicts action based on rules called laws while philosophy calls those rules epistemology.

It is very clear that science is in a very deep rabbit hole right now and there are thousands of very smart science people that argue endlessly about that rabbit hole. Philosophy is a rabbit hole by definition, but the value of philosophy is in defining the limits of what science can know.

This duality is part of nature, just like the mind and body, like subjective and objective, like things in and of themselves versus how they appear...and just like the duality of matter and action. It is from the duality of matter and action that space and time emerge and it is from the duality of philosophy and science that the world makes sense.

Peter Byrne said...

The most interesting thing about this entire thread is how utterly philosophical it is.

Wes Hansen said...

"Time's Arrow and Archimede's Point:New Directions for the Physics of Time," is a very elegant argument from Cambridge philosopher, Huw Price, which I think any scientist would probably benefit from reading; as indicated by the title, it's concerned with the nature of time:

As surveyed by The Information Philosopher, it is somewhat related to the superdeterminism question. Alright, more than somewhat related . . .

Paradoxically, Huw Price is the Director for the University's Centre for the Future of Intelligence, he's a futurist! Sorry, but I just couldn't resist that little zinger . . .

Wes Hansen said...

You know, something else I would briefly point out, converting language to mathematics is not the only way to disambiguate language. Philosophers, the good ones anyway, often disambiguate language by saying essentially the same thing over and over, thirty or forty times, with subtle variations; each variation eliminates one or more potential candidates for the precise entity under discussion; taking all variations together constitutes a precise definition. This is very much analogous to developing an independent postulate set and, while it's probably not the most efficient way to disambiguate a language, it has the added benefit of enabling precise arguments while retaining the full expressive power of the natural language. Good Intellectual Property attorneys are masters at this craft as well; have you ever read a set of claims covering a modern patent? Compare a modern set of claims to a set from yesteryear and you'll see right away what I mean; the old style claims were just too general, too ambiguous . . .

Jonathan Tooker said...

Semantics to be sure, but if physics isn't a sub-discipline of philosophy, then why is the highest achievable degree in physics to awarded a Doctor of Philosophy? What was Newton writing about in his book Mathematical Principles of Natural Philosophy if not physics? The purpose of philosophy is not to advance science but answering the question "How does or can one advance science?" is absolutely a philosophical pursuit, one that physicists are regularly engaged in.

I agree that some fair portion of ``philosophers'' are more or less just trying to hide the inferiority complex they must have over being innumerate, but a few decades or a century of a certain popular flavor of philosophy isn't enough to redefine the scope of the entire philosophical endeavor that stretches back millennia.

Shayne Wissler said...

The statement "Philosophy isn’t useful for practicing physicists" is itself a philosophical proposition -- the cases you'd make for or against it, or the methods you put forth for evaluating these, are not a scientific arguments, they are philosophical (for one thing, consider the meaning of the term "useful"). Ergo, the statement refutes itself.

That said, I'd agree that the practice of philosophy as an institution is a mess and that its overall credibility is questionable. But in principle and if done correctly, philosophy is absolutely indispensable to legitimate science.

Russ Abbott said...

What do you consider the primary branches of physics? Are they (or any of them) independent of each other? Or are they all (or most of them) theoretical (if not practical) consequences of quantum theory, general relativity, and the standard model along with other anchoring observations? Would your answer differ from that of a strict reductionist (if one can imagine such a person)?

In other words, we don't have a "Theory of Everything." As physics now stands which parts fit under a unifying umbrella, and which parts remain stubbornly independent?

In asking this question, I'm not talking about possible bridges from physics to ethics (or anything else). This isn't a Sean Carroll question in that larger sense. But it is a Sean Carroll question in that I'm asking how independent "the many ways of talking about [the] world [are] and [how] different stories we tell can be simultaneously valid in their own domains of applicability. It is therefore distinguished from a hardcore, eliminativist naturalism that says the only things that really exist are the fundamental particles and forces" (

Do you agree with Sean's position (as just quoted)? And if so, what does it mean to say that things other than fundamental particles and forces exist? In your review of Sean's book you wrote that "most people without training in particle physics don’t understand effective field theory, and consequently don’t see what this implies for the emergence of higher level laws." As I understand it (and I'll admit to not being a trained particle physicist), an effective field theory creates an intuitive ontology, one we find convenient. But it isn't a claim that something other than fundamental particles and forces are all there is. The intuitive ontology is just a convenience, not a claim about nature.

Thanks for sticking with me through this comment.

KC Lee said...


Could be wrong, but perhaps no more than superquantumism (Popescu, S. & Rohrlich, D. Found Phys 1994 24: 379. doi:10.1007/BF02058098, and also 2005, DOI: would undercut the scientific method. Both are well worth exploring, given the nearly century-old impasse in physics due to the incongruity of GR and QM.

Sabine Hossenfelder said...


It's not an argument, it's an observation. Funny you'd confuse that...

Sabine Hossenfelder said...


Yes, I agree with that quote from Sean. All statements are resolution-dependent, that's what effective field theory tells you.

I don't have any good answer to what are the "primary branches" of physics. You can look up different areas of research on Wikipedia, if that's what you mean. They are all related of course, in many ways. I think you misunderstand the reason why physicists search for a theory of everything, it's not "independence" which they try to remove but inconsistency. Best,


TheBigHenry said...

Uncle Al,

I passed your latest comment through my gibberish filter (level 4) and it suddenly became clear what philosophy is good for. If you multiply by mass the time derivative of acceleration (which yields jerk), you get a Yank, which in turn, is what the Brits refer to as wank. This then is what constitutes philosophical mental activity.

Charles said...

Henry Pierce Stapp doesn't make the cut?
Something is dreadfully wrong with that!!!


pee puk said...


In a comment you say:

"I think there are some aspects of consciousness that will remain inaccessible for science for a long time, possibly forever."

My take on it:

The reverse engineering of the brain will take some time, but there is zero evidence that some aspects will be inaccessible forever.

Or as a philosopher (Patricia Churchland) framed the "hard problem of consciousness":

"That someone can imagine the possibility is not evidence for the real possibility. It is only evidence that somebody or other believes it to be a possibility. That, on its own, is not especially interesting. Imaginary evidence, needless to say, is not as interesting as real evidence, and what needs to be produced is real evidence."

And here we see another important function of philosophy:

to protect science from philosophy and politics.

KC Lee said...

For some reason, the quote with which my comment on Maudlin began went "virtual" in cyberspace. Bee must think "What is he talking?!" Here it is retrieved:

Could be wrong, but perhaps no more than superquantumism (Popescu, S. & Rohrlich, D. Found Phys 1994 24: 379. doi:10.1007/BF02058098, and also 2005, DOI: would undercut the scientific method. Both are well worth exploring, given the nearly century-old impasse in physics due to the incongruity of GR and QM.

(Hope this makes better sense.)

KC Lee said...

Hmm.. that quote (from this forum) is still missing. Will switch from cut and paste to typing.

Could be wrong, but perhaps no more than superquantumism (Popescu, S. & Rohrlich, D. Found Phys 1994 24: 379. doi:10.1007/BF02058098, and also 2005, DOI: would undercut the scientific method. Both are well worth exploring, given the nearly century-old impasse in physics due to the incongruity of GR and QM.

(Hope the real economy effort would work!)

Uncle Al said...

@ TheBigHenry Bee's essay describes Hohlräume of inquiry. Decorating a surface for social aesthetics is exactly not a path to physical functionality when the boundary is exercised. Cf.: "to grock" If you do not have an improvement, then you do not have a criticism. To criticize is to volunteer.

The Time Derivatives of Distance (given HTML display constraints)

Derivative Name times Mass
0th position moment
1st velocity momentum
2nd acceleration force
3rd jerk yank
4th snap tug
5th crackle snatch
6th pop shake

Shayne Wissler said...


"It's not an argument, it's an observation. Funny you'd confuse that..."

The very first thing I said it was that it was a statement/proposition. Then I talked about the possibility of making arguments for it, and pointed out that all that would just be philosophy. I'm not the one who confused something...

CapitalistImperialistPig said...

Philosophers have proved better at asking questions than providing answers, but now they don't really know enough to ask good questions in most fields.

OT, but I loved your article on your adventures as an autodidact tutor.

Sabine Hossenfelder said...


Pedaling backwards? You write very clearly that you think I am making a "case" for or against that statement. I am not - it's a matter of fact that physicists almost never use philosophy (with the possible exception of quantum foundations which however most other physicists would call philosophy itself...). I am instead saying that something needs to change for it to be no longer useless. Very different thing.

TheBigHenry said...

Thanks, Uncle Al. I knew about the higher time derivatives "snap", "crackle", and "pop" (I ate Rice Krispies when I was a kid, too). But I didn't know the names of their corresponding mass-multiplied properties: "tug", "snatch", and "shake".

TheBigHenry said...

BTW, Uncle Al, you may be interested to know (or possibly not) what the "BlaBlaMeter", which you linked to, had to say about your remarks, "Bee's essay describes ... To criticize is to volunteer."

Here is the output verbatim:

"Your text: 285 characters, 48 words
Bullshit Index :0.67
This reeks. I bet you're a PR-Expert, Politician, Consultant or Scientist. If there is a message, it's unlikely it will reach anyone."

naivetheorist said...


"Personally, I subscribe to a philosophy I’d like to call agnostic instrumentalism, which means I think science is useful and I don’t care what else you want to say about it". i understand the usefulness of various subfields of theoretical physics (e.g. condensed matter and soft matter and biological systems) but i don't see how quantum gravity is useful in any way other than providing employment for some individuals (saying that it serves the purpose of demonstrating the intellectual achievement of the human mind in understanding the universe doesn't work because it has been singularly unsuccessful in doing this). can you give an example of the usefulness of this field (has the the Perimeter Institute produced anything other than speculative theories that have not been experimentally tested?).

best regards,


Phillip Helbig said...

For comparison, I input Lincoln's Gettysburg Address. Output:

Your text: 1480 characters, 276 words
Bullshit Index :0.09
Your text shows no or marginal indications of 'bullshit'-English.

Sabine Hossenfelder said...

More fun with the bullshit index :)

Sabine Hossenfelder said...


You posted this comment in the wrong thread (it's somewhat confusing). With "usefulness" I mean "useful to describe observations." This doesn't imply that a theory must be able to do this while under development, but certainly it should be the goal. I also think that quantum gravity will teach us something about quantum theory that will indeed one day be useful for applications, but I believe not many of my colleagues share my opinion. The reason is that, in contrast to most in the field, I think the problem with quantizing gravity is on the quantum side, not on the gravity side. Best,


Shayne Wissler said...

Sabine -- no, I'm not "pedaling backwards", I'm saying that what you understand by what I said is not what I actually mean. To elaborate further on my original point:

"it's a matter of fact that physicists almost never use philosophy"

The fact is they are constantly using some philosophy, without consciously recognizing that they are, and without being very critical about that philosophy.

Quoting philosopher Brand Blanchard:

"One cannot settle the method of studying a thing without some notion of what the thing is, and a wrong notion may produce a wrong method. It is thus idle […] to profess indifference to philosophy. What such professions commonly mean is not that philosophy is excluded, which is pretty clearly impossible, but that it is admitted unawares in large and dogmatic doses."

To go back to my original point, physicists can *say* that "philosophy is useless", but then when we inquire as to the meaning and veracity of the proposition, they are squarely in a philosophical discussion, which only means they've pulled the rug out from under themselves at the outset, for they can't actually defend that proposition, without contradicting it.

And again, I would agree with you if by "philosophy" we mean merely the profession as practiced by the typical university professor, but philosophy itself is much more than that. Also see "University Philosophy" by Schopenhauer -- he knew how to critique the typical practice of philosophy (in his day), without indicting the discipline as such.

TheBigHenry said...

I grew up with "Strunk & White" as a freshman at Cornell. So, just for grins, I passed Strunk's 1918 recommendation thru the BS meter:

"Vigorous writing is concise. A sentence should contain no unnecessary words, a paragraph no unnecessary sentences, for the same reason that a drawing should have no unnecessary lines and a machine no unnecessary parts. This requires not that the writer make all his sentences short, or that he avoid all detail and treat his subjects only in outline, but that he make every word tell."

Your text: 384 characters, 66 words
Bullshit Index :0.05
Your text shows no or marginal indications of 'bullshit'-English.

After all these years, it's a relief to know this.

TheBigHenry said...

One last thing, Uncle Al. For "snap", "crackle", and "pop", I would have chosen the mass-multiplied property names "shake", "rattle", and "roll", respectively.

Sabine Hossenfelder said...


Yes, when I say they don't use philosophy I mean they don't use anything produced by the currently practiced professionals. Yes, they are using philosophical arguments without noticing, as I have pointed out (here and elsewhere).

Phillip Helbig said...

"This reeks. I bet you're a PR-Expert, Politician, Consultant or Scientist."

My emphasis. So, the blablameter lumps us in with these folks?!

Phillip Helbig said...

One last thing, Uncle Al. For "snap", "crackle", and "pop", I would have chosen the mass-multiplied property names "shake", "rattle", and "roll", respectively.

Recently, I was reading a book on relativistic cosmology, where the author mentioned "snap, crackle, and pop" for the third, fourth, and fifth derivatives, respectively. As the book was (though very good) not otherwise humorous, I assume that this is standard usage.

TheBigHenry said...

Phillip Helbig,

Yes, these are, in fact, defined terms for higher derivatives (beyond velocity, acceleration, and jerk) of position with respect to time. See Wikipedia:

JimV said...

"@jimV scientism is a philosophy"

True, and a good one, too!

To show that I am not inimical to philosophy in general (mainly just to dualistic philosophy) I will submit my own philosophical principle of Mario's Sharp Rock: when there exist more than one possible hypothesis, yada yada yada, chose the most humble one.

Alan Saeed said...

One question that has been taken over by scientists, even engineers, is the philosophical question of local reality. Now this question is being pursued by practical researchers and engineers developing quantum computers. The question of local reality is no longer a philosophical one.

coraifeartaigh said...

I would like to add Julian Barbour and Simon Saunders to your list, Bee - excellent representatives of a species that lies somewhere between physics and philosophy. They often don't get counted as philosophers, yet their work can be most helpful and clarifying to physicists.
That said, I sometimes I find myself in agreement with Larry Krauss. This week, I have been trying to find a single philosopher who considered the concept of a non-static universe *before* the advent of theory (GR) or observation (Hubble's law). Not one so far...
Regards, Cormac

regretacles said...

"Philosophy isn’t useful for practicing physicists"

Husserl was a huge influence on Weyl's sense of the role of infinitesimal geometry in physics and his invention of Gauge theory. Here, let me fix your mis-statement for you:
"Philosophy *of science* isn't useful *for scientists*."

Chris Stephens said...

I'm surprised you didn't mention Amit Hagar as one of the philosophers of physics you like - he has a book on the history and philosophy of physics (Discrete or Continuous) that you might find of interest.

As to the more general question as to why philosophy isn't useful for practicing physics, here are some speculative answers:

1. Many philosophers don't have adequate training in both physics and philosophy -
2. There aren't that many philosophers of physics relative to the number of physicists (I'm not saying that's a bad thing!). But this means there are probably lots of areas of physics that might benefit from the kinds of conceptual clarification that philosophers are supposed to be good at but no philosophers are working on them.
3. Many of the questions philosophers of physics are interested in just aren't of interest to physicists. After all, much of philosophy of science - like history of science - is a "second order" discipline about science itself. Scientists, not surprisingly, want to get on with the business of doing science. This is part of Massimo's point, I gather. Just as there are questions about the history of physics that are primarily only of interest to historians, so with philosophy of physics.

Take all three points together and you can see why there will be very few practicing philosophers of physics that physicists will find directly relevant to their own work. there are of course, philosophers of physics who publish in physics journals, but when they do, they're often not even recognized as philosophers (e.g., someone mentioned they didn't even know Weinstein was a philosopher).

ljuhan2 said...

You state very clearly in the comments that philosophers shouldn't discuss laws of nature without knowing what Hamiltonian evolution is, and shouldn't discuss emergence without knowing field theory.

I am sure that such knowledge would benefit philosophers greatly, however, since I am not familiar with the said theories, I was wondering if you can help me and explain just how such theories illuminate the specifics of debates around those topics that circulate in professional philosophical journals?

For example, how does Hamiltonian field theory reflect on the debate between systems (Lewis) and universals (Armstrong) conceptions of laws of nature? Also, what are the consequences for the claim of Humean supervenience (debated by Earman, Carrol, Lewis, Maudlin)?

As far as emergent properties and field theory are concerned, how does field theory settle the issue of Kim's downward causation argument, and what are the consequences for non-physical explanatory practices if indeed emergent properties are epiphenomenal, as Kim says?

I think that your argument would be extremely convincing if you could substantiate it with clear examples of those physical theories making a difference in actual philosophical debates.

Sabine Hossenfelder said...


It's an excellent question, but not one that I could answer in a few paragraphs. An excellent starting point would be Sean Carroll's new book. Best,


Sabine Hossenfelder said...


Ah, yes, you are right! How could I forget about Amit. Yes, I know his book and wrote about this here.

ljuhan2 said...

Sabine Hossenfelder,

I guess I'll have to go back and read Carroll's book more carefully. I skimped through it and didn't find anything that I would think would interest a professional philosopher, and that is particularly original. Most of it are things that are well known in philosophical circles, for decades (see for example Carroll's discussion on Jackson's knowledge argument, in which Carroll basically recycles Nemirow's ability hypothesis; and similar). It seems to me that, while philosophers are often guilty of being condescending towards physicists and other scientists, the reverse is also true sometimes, and scientists who express a strong criticism of philosophy are often not very well acquainted with what goes on in professional philosophical journals.

But it might be that I just didn't read Carroll carefully enough, thanks for the suggestion.

Sabine Hossenfelder said...


I am somewhat puzzled by your comment because I thought Carroll explains effective field theory very clearly, in particular for what downward causation (or its absence) is concerned.

His discussion of the different languagues that apply at different levels of resolution is, I think, relevant for some topics that (for all I know) fall into the realm of metaphysics - what's a thing, what's a property of that thing, what's a statement (true statement) about the properties of that thing, is a "chair" a thing or are only its constituents things and so on. I find it somewhat strange admittedly that one can even try to discuss these question without speaking of emergence and effective field theory.

I don't know about the specific questions that you ask, I'm not familiar with these discussions, sorry.

Jeffrey Ketland said...

Sabine, "If you want to know “what follows from what,” as Maudlin writes, you have to convert language into mathematics and thereby remove the ambiguities. Unfortunately, philosophers never seem to take that step, hence physicists’ complaints that it’s just words."

Hartry Field did that in his book Science Without Numbers, 1980.

In connection here with "what follows from what", Field did prove a certain kind of conservation result. This is the following: if N is a theory referring only to concrete objects, and M is some standard mathematical axioms, then N+M proves no more about the concrete stuff that N does. For example, suppose we have the theory of concrete things, N = "there are seven cats c1, ..., c7, and c1 is heavier than c2, c2 is heavier than c3, ... c6 is heavier than c7; and heavier-than is transitive, irreflexive and asymmetric", and also the mathematical axiom scheme, for any condition F in the N-language), M = "there is a unique set X such that, for any concrete thing x, x is in X iff x satisfies condition F".
It follows that if N+M implies a statement A, then N implies A (where A is in the N-language).

So, philosophers have done what you asked and proved detailed results about it.
There's more about this kind of thing in

Burgess & Rosen 1997, A Subject with No Object.

Sabine Hossenfelder said...


Thanks for the references, that's lovely! I'll have a look at this :)

Shayne Wissler said...

I think it would be helpful in this discussion to more sharply distinguish between philosophy as a credentialed discipline, and philosophy as such; otherwise, the failures of former tends to obscure the role philosophy could and should play.

The failures of philosophy as a discipline are of course not constrained to physics. To pick just one example: Ask a legislator why he has passed a given law, whether it is actually just, and so on, and you can observe the impotence and truancy of philosophy as a discipline -- for just whose job was it to educate this legislator concerning the ethical nature of his legislation in the first place? He went to university, and yet he leaves it totally ignorant of the proper ethical basis of the law. To find the source philosophy's problem, we might begin by considering Schopenhauer: "... if there is to be a philosophy at all, that is to say, if it is to be granted to the human mind to devote its loftiest and noblest powers to incomparably the weightiest of all problems, then this can successfully happen only when philosophy is withdrawn from all State influence."

Regarding philosophy as such, every physicist brings whatever philosophy he has to every problem he considers, and these are not constrained to physics problems per se, they include such things as: how to do peer review; who to grant the PhD to and why; who to include or exclude in various institutions and why, or in general, how best to protect the integrity of the institutional practice of physics; how to decide what deserves funding priority; how to interpret experimental results and mathematical calculations, including an idea of what sorts of interpretations should count as making sense or not, and whether to allow explicit philosophical considerations to influence these or not; etc.

In other words, philosophy *as such* is not merely used by physicists, it's intensively and constantly used, even if the particular physicist making these various decisions is blissfully unaware of this. The question then is not whether philosophy is used, but whether the individual philosophies of physicists are brought into the open and rationally scrutinized, and with the aim of finding some semblance of discipline and unity, or whether it remains an unaccountable mass of uncritically examined subtexts.

The systematic examination and evaluation of the individual philosophies of physicists is something one would hope that institutionalized philosophy could do well. But this would require two things: 1) regarding this examination, the philosophy discipline would have to actually be credible and worth listening to, and 2) individual physicists would have to submit their beliefs to such an examination. Neither seems likely in the near term.

Sabine Hossenfelder said...


I agree with that.

Naji Rodes said...


"It is obvious (to me) that one cannot go from a fact statement to a value statement. a statement such as "because of fact A, you ought to do B" is nonsensical and only makes sense if it is changed to "because of fact A, you ought to do B, IF you want to accomplish C" yet i have never known of a single philosopher who realizes this."

What about Hume himself? Doesn't he count as a philosopher?

Wilfredo Yambao said...

Undoubtedly, you wrote a great article Sabine. I got, nevertheles, what Pigliucci meant when he said that cosmology is bad philosophy. But he forgot to mention that the old classical philosophical materialism is a false dichotomy. It is a false dichotomy because it argues a false distinction. As we know now, the two concepts (philosophical idealism and philosophical materialism) are mismatched, there is no contradiction between them for they both uphold creation. As we know now, the great basic question that split philosophy into two great camps is the relationship between thinking (internal reality of the mind) and being (external reality) or the relationship between the primacy of Spirit to Nature. Those who answered that Spirit (idea or cosciousness) is primary belonged to the various schoos of philosophical idealism. And those who answered that Nature is primary belonged to the various schools of philosophical materialism. According to the new theory of knowledge, the two mismatched concepts always lead to creation and because it is always linked to religion eventually confusion. I say that physicists and cosmologists are effectively engaged and contained with the creation mojo because Albert Einstein brought the issue of creation into the realms of a scientific theory. His masterwork, GR, beautifully concealed the issue of creation. In short, his dual tactics policy of engagement and containment work effectively. No one can deny that physics is principally engaged in finding a principle that undergirds universe creation. To me, that is a great deflection with respect to the intellectual struggl. Hence, in that context, cosmology is bad philosophy. Willy Whabit.

Wes Hansen said...

Well, with regards to dualism, consider the following from George Ellis:

“Causation: The nature of causation is highly contested territory, and I will take a pragmatic view:

Definition 1: Causal Effect If making a change in a quantity X results in a reliable demonstrable change in a quantity Y in a given context, then X has a causal effect on Y.

Example: I press the key labelled “A” on my computer keyboard; the letter “A” appears on my computer screen.

Existence: Given this understanding of causation, it implies a view on ontology (existence) as follows: I assume that physical matter (comprised of electrons, protons, etc.) exists. Then the following criterion for existence makes sense:

Definition 2: Existence - If Y is a physical entity made up of ordinary matter, and X is some kind of entity that has a demonstrable causal effect on Y as per Definition 1, then we must acknowledge that X also exists (even if it is not made up of such matter).

A: Causal Efficacy of Non Physical entities: Both the program and the data are non-physical entities, indeed so is all software. A program is not a physical thing you can point to, but by Definition 2 it certainly exists. You can point to a CD or flashdrive where it is stored, but that is not the thing in itself: it is a medium in which it is stored. The program itself is an abstract entity, shaped by abstract logic. Is the software “nothing but” its realisation through a specific set of stored electronic states in the computer memory banks? No it is not because it is the precise pattern in those states that matters: a higher level relation that is not apparent at the scale of the electrons themselves. It’s a relational thing (and if you get the relations between the symbols wrong, so you have a syntax error, it will all come to a grinding halt). Furthermore it is not the same as any specific realisation of that pattern. A story can told (and so represented in sound mediated by air vibrations), printed in a book, displayed on a computer screen, attended to in ones mind, stored in one’s memories; it is not the same as any of these particular representations, it in itself is an abstract thing that can be realised in any of these ways; and it is the same with computer programs: they are abstract entities that can be physically realised in many different ways, bit no particular one of them is the same as the story itself. They are its varied representations. This abstract nature of software is realised in the concept of virtual machines, which occur at every level in the computer hierarchy except the bottom one [17]. But this tower of virtual machines causes physical effects in the real world, for example when a computer controls a robot in an assembly line to create physical artefacts.”

With that fresh in mind, consider the following from Alain Connes, Connes being considered, as most probably know, a foremost authority on Quantum Field Theory. The following is from, “The Riemann Hypothesis,” by Karl Sabbagh:

“It is quite amazing to realize that our simpleminded materialistic conception of external reality is really built on quicksand, and that after a while the only real thing you can cling to is much more abstract. Just let me give you a concrete example of that. If you take one individual, most of his cells are actually replaced totally over a period of several years, so what is he? Is he a collection of cells? Certainly not, because precisely these cells are replaced. But what he is is something quite different – it’s a scheme. The only thing that is pertinent is the scheme, the organization. Quantum mechanics is extremely striking in that respect, because it makes it clear that even if you try to cling to external matter as being reality, you will find that as soon as you go to the sufficiently small, then precisely because of quantum mechanics you will come across inconsistencies, so you can’t rely on that as being the ultimate reality.”

Wes Hansen said...

Do to a comment by Matthew Rapaport, I'm inclined to clarify, the above comment is in no way, shape, or form an endorsement of mathematical realism - I'm a humanist! I do, however, find the materialist position to be simple-minded to the extreme, especially in light of the modern physics, not the least of which being QFT. In fact, I find the materialist position to be disingenuous, by which I mean, "not candid or sincere, typically by pretending that one knows less about something than one really does." The definition is from Google's dictionary.

With regards,
Wes Hansen

Tam Hunt said...

This piece is interesting but betrays the author's neophyte status in philosophy. It's like if I said, as a philosopher: "I've surveyed the field of physics (a less generalized form of philosophy) and have concluded that there are only three physicists worth taking seriously." Why insult a whole field, particularly coming from a position of ignorance as you do?

Sabine Hossenfelder said...


Not only didn't I write that there are only three philosophers taken seriously (I wrote that's what I've been told, and it's quite literally what I've been told, sorry) but that what I wrote was clearly a joke. I've explained very clearly that I think there's a lack of communication between physicists and philosophers. If I praise philosophers, no physicist will listen to me. If I praise physicists, no philosopher will listen to me. It's a difficult line to walk. Now read again what I wrote, this time without assuming it was written for you personally, and maybe you'll understand it this time.

Phillip Helbig said...

"Recently, I was reading a book on relativistic cosmology, where the author mentioned "snap, crackle, and pop" for the third, fourth, and fifth derivatives, respectively. As the book was (though very good) not otherwise humorous, I assume that this is standard usage."

I have now reviewed the book, which I recommend.