On the relation between physics and philosophy

[PeroK]

I don't know much about either philosophy or physics so consider the following to be naive.

It seems that one goal of Physics is to come up with Physical principles such as "the speed of light is constant in all inertial frames of reference." Where did this goal come from if not from some philosophical bias?

- Pure observation suggests that a body in motion if not subjected to outside forces comes to its natural state of rest. Roll a ball. It eventually stops. Keep on pushing a wagon if you want to keep it moving. Why would one make such a conclusion from pure observation? Why not just say "I rolled the ball and it came to rest?".

- The Ptolemaic system for describing the orbits of planets, though approximate, can be calibrated to be extremely accurate and to give good predictions for long periods of time. When it goes noticeably wrong it can be adjusted back into line. Why not stick with this empirical method which is stable and can be made as accurate as one wants? Why invent the Copernican system and then Kepler's theory?

- It seems Physics is searching for a unity which that will reveal in some sense the "true Nature" of creation. To me this is intrinsically a philosophical if not an outright teleological goal. Mere description of phenomena even when it employs predictive rules, cannot tell you the answer.

- It seems that Quantum Mechanics and Classical Physics by themselves indicate that there is no such unity to creation. Some new way of thinking is needed. I think Physicists are well aware of this. To me this why merely accepting Quantum Mechanics as a set of rules that work - much like the Ptolemaic System - is unappealing. This even though Quantum Mechanics seems precise rather than approximate.

I don't get any of this!

 

[Rollo]

Leaving aside quantum foundations, which is an active area of interdisciplinary research involving physicists and philosophers, there are a number of other live questions in contemporary physics where I think a philosophically informed perspective is valuable.

For example: the soundness and significance of anthropic arguments; the role of aesthetic and other qualitative factors in theory evaluation.

As others have pointed out, historically philosophical considerations were certainly important in significant scientific discoveries such as relativity (Einstein himself talked about the influence of Hume on his work, see here: https://aeon.co/essays/what-Albert-einstein-owes-to-david-humes-notion-of-time). More generally - most of the physicists of that vintage would have been knowledgeable about philosophy: this would have been the case with anyone educated to that level in the European university system of the time.

Further back, of course, the distinction between the disciplines becomes murkier (e.g. Newton would have regarded himself as a philosopher).

 

[PeroK]

Leaving aside quantum foundations, which is an active area of interdisciplinary research involving physicists and philosophers, there are a number of other live questions in contemporary physics where I think a philosophically informed perspective is valuable.

For example: the soundness and significance of anthropic arguments; the role of aesthetic and other qualitative factors in theory evaluation.

As others have pointed out, historically philosophical considerations were certainly important in significant scientific discoveries such as relativity (Einstein himself talked about the influence of Hume on his work, see here: https://aeon.co/essays/what-Albert-einstein-owes-to-david-humes-notion-of-time). More generally - most of the physicists of that vintage would have been knowledgeable about philosophy: this would have been the case with anyone educated to that level in the European university system of the time.

Further back, of course, the distinction between the disciplines becomes murkier (e.g. Newton would have regarded himself as a philosopher).

The question is, assuming modern physicists lack the philosophical knowldege of their predecessors, is this holding them back? Or, despite the success of Einstein, did philosophical considerations in the past hold back physics for many decades? Perhaps preventing many 19th century physicists breaking free.

You could certainly make a case that, for example, religious and philosophical ideas inhibited Darwin from publishing the Origin of the Species.

Even in mathematics, complex numbers were suppressed for philosophical reasons.

I'm not convinced by the argument that philosophy has eased the path of science. I believe you could make a stronger case that, quite the reverse, philosophical preconceptions have repeatedly held science and mathematics back.

 

[Elias1960]

You are forgetting that papers are also rejected by journals simply because they aren't good enough for the journal, not because of their topic.

No. I predicted the fate of a paper proposing a theory of quantum gravity which needs a preferred frame and a condensed matter interpretation. I did not make assumptions about its other qualities, thus, those other qualities are irrelevant for my prediction.

 

[PeterDonis]

I predicted the fate of a paper proposing a theory of quantum gravity which needs a preferred frame and a condensed matter interpretation.

You predicted that such a paper would not be published in peer-reviewed journals. But, as I have already pointed out, the physicist whose paper you linked to has had papers proposing such a theory published in peer-reviewed journals, as a simple check of his web page will show you.

You have now been banned from further posting in this thread.

 

[Julius Ceasar]

You could certainly make a case that, for example, religious and philosophical ideas inhibited Darwin from publishing the Origin of the Species.

Religion for sure has inhibited scientific ideas throughout history and used its philosophy to do so. I mean are you telling the whole story here and philosophy just the unintentional patsy.

 

[Demystifier]

I don't know about that. I seem to recall that as recently as 1900 people doubted that atoms "really' exist. Including physicists like Ernst Mach.

Mach was completely against atoms, he didn't say that they are just a "computational tool".

 

[Demystifier]

How is quantum mechanics different?

Quantum mechanics "itself" (as opposed to what we call interpretations of quantum mechanics) does not say whether the wave function exists irrespective of measurement, to give just one example.

 

[vanhees71]

Classical mechanics does not say whether position and momentum vectors exist irrespective of measurement either...

 

[Demystifier]

The question is, assuming modern physicists lack the philosophical knowldege of their predecessors, is this holding them back?

The problem for the work in foundations of physics is not the lack of philosophical knowledge. The problem is the lack of philosophical mode of thinking. A physicist does not need to know what Kant or Aristotel or Hume said to be a good philosopher of physics. What he needs is to be able to be in a mode of thinking in which the sentence "Is wave function real?" does not sound like a meaningless gibberish.

 

[martinbn]

Quantum mechanics "itself" (as opposed to what we call interpretations of quantum mechanics) does not say whether the wave function exists irrespective of measurement, to give just one example.

Because the question doesn't make sense.

 

[martinbn]

The problem for the work in foundations of physics is not the lack of philosophical knowledge. The problem is the lack of philosophical mode of thinking. A physicist does not need to know what Kant or Aristotel or Hume said to be a good philosopher of physics. What he needs is to be able to be in a mode of thinking in which the sentence "Is wave function real?" does not sound like a meaningless gibberish.

Good philosophy helps you to see that the question is gibberish.

 

[Demystifier]

Because the question doesn't make sense.

It seems that quantum mechanics is the only branch of physics that contains questions which "don't make sense".

 

[Demystifier]

Good philosophy helps you to see that the question is gibberish.

Which philosophy is that? Logical positivism?

 

[martinbn]

It seems that quantum mechanics is the only branch of physics that contains questions which "don't make sense".

You can ask that question in any branch. Why just QM, I don't know, you tell me.

 

[martinbn]

Which philosophy is that? Logical positivism?

No, just basic philosophy.

 

[Demystifier]

No, just basic philosophy.

Which is that? Where can I read the book "Basic philosophy for physicists"?

 

[Demystifier]

Why just QM, I don't know, you tell me.

I already did.

 

[Rollo]

The question is, assuming modern physicists lack the philosophical knowldege of their predecessors, is this holding them back? Or, despite the success of Einstein, did philosophical considerations in the past hold back physics for many decades? Perhaps preventing many 19th century physicists breaking free.

You could certainly make a case that, for example, religious and philosophical ideas inhibited Darwin from publishing the Origin of the Species.

Even in mathematics, complex numbers were suppressed for philosophical reasons.

I'm not convinced by the argument that philosophy has eased the path of science. I believe you could make a stronger case that, quite the reverse, philosophical preconceptions have repeatedly held science and mathematics back.

In terms of philosophical knowledge holding back vs. advantaging physicists, a few thoughts:

1. One of the difficulties here is disentangling formal philosophical commitments from philosophical background assumptions and ideas that we all have. For example (off the top of my head not researched) - the uptake of the big bang hypothesis was probably slowed by people finding the idea of the universe coming into being ex nihilo absurd. This is of course a philosophical thought of long pedigree, but also a perfectly natural intuition that people might have absorbed without specific exposure to it, or arrived at themselves.

2. I wouldn't necessarily assimilate people being resistant to new ideas because they conflict with philosophical principles with their being reluctant to contradict religious doctrines - either because they themselves hold to these or because of social pressure. These *could* be similar but are probably often not. Being reluctant to contradict received opinion has nothing specifically to do with philosophy.

3. More generally - my instinct is that this probably in part relates to the distinction between Kuhnian normal vs revolutionary science. I.e. in a period of 'normal' science, solving problems within a for-the-moment unquestioned framework, knowledge of philosophy is neither helpful nor unhelpful, and probably no more relevant to the practice of science than, e.g., what type of music the scientists listen to. However in a period of 'revolutionary' science , when a new paradigm is being formed, philosophical beliefs may inspire (as in the case of Einstein or Bohr) or hinder this process.

On a personal note, my background is in philosophy (I'm recreationally self-studying physics), and one of the things that I have noticed re this is that thinking about philosophy does cultivate a facility for what I'd call intuitive flexibility, basically being open to new ideas even if they are 'weird'. Crudely - if you spend a bit of time trying to think yourself into what it's like to hold, e.g., the metaphysics of Leibniz's Monadology or Spinoza's Ethics, then ideas like Everettian QM, or the world being 11 dimensional, don't seem that odd anymore!

 

[A. Neumaier]

If on follows Wilson, so what? Field theories are large distance approximations of unknown low distance theories

This doesn't change the fact that all effective theories of interest in high energy physics are relativistic quantum fields theories and not lattice theories! Wilson's lattice ideas don"t play any role there - except in one of several approaches to QCD, which is only a small part of the standard model.

 

[RUTA]

I’ve been working closely with a philosopher of science in foundations of physics for the past 25 years. When we first met, I was trying to answer Mermin’s challenge (1981 Am. J. Phys. paper “Quantum mysteries for anybody”) as a typical theoretical physicist, i.e., induced spacetime metrics from uniform spaces over group structures. Really cool math, but absolutely worthless physics. His ideas and questions got me to abandon my technical approach and find a real physics answer. Answering Mermin’s challenge has been the highlight of my career and I owe it to a philosophical method of inquiry that my training in physics did not provide.

 

[gleem]

You cannot be a physicist without being a philosopher since you have a specific view of knowledge. Another physicist looks at the relation of philosophy to physics

https://www.scientificamerican.com/article/physicists-are-philosophers-too/Rovelli gave a lecture at the Center of Philosophy of Natural and Social Science of the London School of Economics. It is the same content as the OP cited publication but has a different feel something a paper cannot reproduce.

https://www.artandeducation.net/classroom/video/197528/carlo-rovelli-why-physics-needs-philosophy

 

[Julius Ceasar]

Philosophy may well invite the weirdos with some ulterior motive they are perusing but it is an adolescent child that refuses help when they're stuck because they must do it all themselves.

 

[Julius Ceasar]

Thanks gleem I read the whole article, "physicists are philosophers too" i liked it a lot. See this excerpt-
"Philosophers from the time of Plato and Aristotle have claimed that knowledge about the world can be obtained by pure thought alone. As Tyson explained, such knowledge cannot be obtained by someone sitting back in an armchair." I would never endorse working out what's true by pure thought alone but to suppose it can't ever be useful is ridiculous to me. Pure thought alone is a great tool for ruling out what is least likely.
Krauss is the author of a book called, "A Universe from Nothing", nothing begets nothing, pure thought alone tells me this.

 

[PeroK]

Pure thought alone is a great tool for ruling out what is least likely.

And that is precisely the problem. It does no such thing. Physics you learn from what nature tells you.

For example: why, using pure thought alone, is gravity attractive and not repulsive?

 

[Julius Ceasar]

As for your example I would never endorse working out what's true by pure thought alone. Getting something from nothing? Not very likely but still I would go with the evidence because the use of philosophy does not preclude using science.

 

[PeroK]

As for your example I would never endorse working out what's true by pure thought alone. Getting something from nothing? Not very likely but still I would go with the evidence because the use of philosophy does not preclude using science.

In other words, you can only deduce from pure tought what turns out to be true when you do an experiment! So, you have no way to tell, until you do an experiment, which of your pure thoughts represents nature and which do not.

"Getting something from nothing" has no scientific meaning. Sitting in a room debating a question like that is pointless. That's not science.

 

[Julius Ceasar]

when you do an experiment!

what experiment?

 

[PeroK]

what experiment?

To test your pure thought against nature.

 

[Julius Ceasar]

Sorry i wanted to know what experiment you could come up with to show how you can get
"a universe from nothing" as per the title of krauss's book.

 

[PeroK]

Sorry i wanted to know what experiment you could come up with to show how you can get
"a universe from nothing" as per the title of krauss's book.

If you want to debate that specific issue, I suggest you start a thread on it.

 

[Julius Ceasar]

I don't think it deserves debating from a pure thought perspective which was the point.

 

[PeroK]

I don't think it deserves debating from a pure thought perspective which was the point.

You mean that you can deduce from pure thought from the comfort of your armchair some basic criteria for cosmological theories?

And that's brilliant, because then you don't need to trouble yourself with the hard stuff like learning GR, QM or any mathematics.

Or, even concern yourself with the issue that perhaps all you're doing is just a meaningless playing with words.

 

[PeroK]

@Julius Ceasar I just realized that Shakespeare got there first:

"There are more things in heaven and earth, Horatio,
Than are dreamt of in your philosophy. "

 

[Julius Ceasar]

Its not one or the other, i am not asking you to debate the specific issue but i am asking if you could.