You are viewing the historical archive of The Philosophy Forum.
For current discussions, visit the live forum.
Go to live forum

Does doing physics entail metaphysical commitments?

ProcastinationTomorrow April 05, 2018 at 09:29 12975 views 42 comments
Another discussion stream on commonsense and physics lead me to take a look at a website dedicated to metaphysics where I read this blog piece
https://metaphysicsnow.com/2018/03/21/stephen-hawking-a-scientist-dies-philosophy-lives-on/
Not sure I completely understand it, but the general idea seems to be that modern physics is up to its eyeballs in metaphysical commitments it has nothing to say about. Doesn't seem correct to me - I've met a few physicists in my time and they tend to think that what they are doing commits them to nothing other than constructing models. Are they wrong about that?

Comments (42)

numberjohnny5 April 05, 2018 at 10:30 #169683
I look at it this way. Science and philosophy, while sharing some similarities, are methodologically distinct: the former is generally more experimental, and the latter generally more analytical.

According to their (constructed) models, some scientists make ontological/metaphysical commitments and some make ontological/metaphysical claims (where claims/proposals don't necessarily equate with commitments). Both approaches (commitments or claims) can still allow for practical development in science. This is because there can be instrumental value (i.e. instrumentalism) in how commitments/claims help develop ideas and outcomes, regardless of whether the commitments/claims are ontologically true.

ProcastinationTomorrow April 05, 2018 at 11:04 #169688
Reply to numberjohnny5 The difference between an ontological claim and an ontological commitment is what, as far as you understand it? Is it that the former is always explicit, the latter not always so (i.e. might be implicit only in the use of such things as the principle of least action, as the web article suggests)?
numberjohnny5 April 05, 2018 at 11:21 #169691
The difference between an ontological claim and an ontological commitment is what, as far as you understand it?


Firstly, some ontological claims are identical with ontological commitments. That's why I wrote "where claims/proposals don't necessarily equate with commitments."

Ontological claims can be logical propositions about stuff that don't need to be committed to. For example, "I propose that based on model x and model y, String Theory could be true, but I'm not making an ontological commitment to it being true. String Theory could be true; it could also be false."

Ontological claims that aren't made from this logical perspecitve are identical to ontological commitments, which require a belief that some thing is the case, and it's not just a proposal one is considering or holding as a counterfactual, for example.
Artemis April 05, 2018 at 23:46 #169792
Quoting ProcastinationTomorrow
they tend to think that what they are doing commits them to nothing other than constructing models.


The scientific models allows for scientists to avoid absolute "commitments" because they are working with hypotheses and theories. The (good) scientist tests his/her hypotheses and upon reaching a point where it doesn't work, can go back and edit their assumptions until they find out what does work.

So, for instance, the scientist dropping an apple on the ground to test gravity assumes s/he and the apple are real--perhaps it would be difficult for the scientist to adjust a hypothesis if s/he found out his/her own existence was false :joke: but if the apple turned out not to exist, or be a helium balloon, or something like that, the scientist could, should, and hopefully would go back to the drawing board.

Of course, I'm talking about the ideal scientist--it is likely that many scientists could not be so open-minded about some of their metaphysics, especially those beliefs that we all rely on in our day to day lives.
_db April 06, 2018 at 00:03 #169799
Quoting ProcastinationTomorrow
Doesn't seem correct to me - I've met a few physicists in my time and they tend to think that what they are doing commits them to nothing other than constructing models. Are they wrong about that?


Seems to me that constructing models requires background assumptions - that's all metaphysics is, at least in the sense philosophy of science tends to use. Fundamentally, to construct models about reality presupposes that reality has some kind of formal, rational structure that can be modeled, typically with the use of numbers and logic.

Generally scientists are at least methodological, if not metaphysical naturalists, and work on science within this naturalistic framework. When approaching a question about the world, the explanation sought is one that is naturalistic and has no reference to something that cannot, in principle, be studied by science. Note that this does not entail circular scientism but rather is merely a methodological bracketing-off of anything not within the parameters of science.

Then, of course, there are the assumptions that other people do in fact exist, that there is actually a real, external world that continues to exist without our participation, that there are "laws" that are explicable mathematically, etc. Sometimes assumptions are proven false, or have to be revised: we call these paradigm shifts. Look at special relativity, biological evolution, quantum mechanics, etc.

Basically, then, if science is the study of the ontic, phenomenal, natural world, then there must be some basic assumptions ("metaphysical" ones), that are required for science to even get off the ground. These don't need to be complex, necessarily, and I hardly think scientists "need" metaphysicians to help them out. What's important to remember is that these are metaphysical, and not scientific, and that they can be up for debate, and, historically, have been. What's dangerous and incorrect is the ahistorical belief that science has operated under one continuous framework since its "inception", whenever that is claimed to be.
Wayfarer April 06, 2018 at 00:18 #169802
A lot of physics is done according to the ‘shut up and calculate’ approach, which means NOT discussing the various philosophical quandaries that are thrown up by physics, and just keeping your head down.

On the other hand, there is a huge and highly charged debate going on in current physics and cosmology, as to whether string theory and the speculative multiverse that flows from it, is really a matter for science or not. On the Nay side are those who say that these ideas can never be falsified even in principle, as they concern matters which are by definition outside the universe. On the Yay side are those who say that, because of the compelling nature of the mathematics and the solutions that these models offer to many intractable problems, then such speculations should be regarded as within the ambit of science. So part of this, is actually discarding Popper's idea of 'falsifiability' as a criterion for what constitutes a scientific hypothesis. And this is a debate that doesn't look like finishing any time soon. (Lots of useful discussion of it on Peter Woit's website Not Even Wrong, from the Nay perspective.)

On the other hand - one of the consequences of so-called Enlightenment thinking, is that science, and specifically physics, will do away with a lot of the 'fog of metaphysics'. It was felt that the useless scholastic blatherings about 'angels on the head of a pin' could be blown away by firm concentration on the undeniable objects of the physical realm.

Shame about [s]supervenience[/s] superposition, then.
Joshs April 06, 2018 at 01:36 #169820
Reply to Wayfarer Enlighenment science may have gotten rid of one ‘fog of metaphysics’ only to replace it with the fog of physicalism. At least , according to a different and more more encompassing way ofunderstanding metaphysics than just via the issue of whether science can describe all aspects of reality.
According to this alternate perspective, any science , in any era, is always already a philosophical worldview , articulated via a particular vocabulary and methodology that marks it as science according to the conventions of that era.
A hot topic in current philosophy of mind is whether it’s time to jettison objectivist and physicalist presuppositions in the hard sciences, and how such a rethinking would change how science is practiced.
Nelson Goodman recognized the dependence of the objects of science on subjective construction.
“If the composition of points out of lines or of lines out of points is conventional rather than factual, points and lines themselves are no less so. ... If we say that our sample space is a combination of points, or of lines, or of regions, or a combination of combinations of points, or lines, or regions, or a combination of all these together, or is a single lump, then since none is identical with any of the rest, we are giving one among countless alternative conflicting descriptions of what the space is. And so we may regard the disagreements as not about the facts but as due to differences in the conventions-adopted in organizing or describing the space. What, then, is the neutral fact or thing described in these different terms? Neither the space (a) as an undivided whole nor (b) as a combination of everything involved in the several accounts; for (a) and (b) are but two among the various ways of organizing it. But what is it that is so organized? When we strip off as layers of convention all differences among ways of describing it, what is left? The onion is peeled down to its empty core.”
Cuthbert April 06, 2018 at 07:17 #169849
I think the idea of an initial singularity entails that the principle of sufficient reason is false but I've never seen a discussion of that problem - maybe because I haven't looked hard enough or because there is no entailment. Or because we can jettison sufficient reason without caring much. I don't know.
ProcastinationTomorrow April 06, 2018 at 07:27 #169855
Reply to Cuthbert Hello Cuthbert - small clarification, the article I cited is talking about the principle of least action, not the principle of sufficient reason. I can see why an intial singularity would be anathema to the principle of sufficient reason, but not the principle of least action.
ProcastinationTomorrow April 06, 2018 at 07:32 #169859
Reply to darthbarracuda "..I hardly think scientists need metaphysicians to help them out". The article seems to suggest precisely the opposite. The idea seems to be that the principle of least action commits scientists to possibilia, scientists only treat of actuality, so metaphysicians must step in to sort it all out. I'm not saying the article is right about that by the way - but I do agree that scientists who think metaphysics should be buried are wrong.
Cuthbert April 06, 2018 at 08:51 #169871
Reply to ProcastinationTomorrow Sure, but the general point that "modern physics is up to its eyeballs in metaphysical commitments it has nothing to say about" perhaps applies. I hear the impatience in the replies of physicists to the question 'What came before the Big Bang?' or 'What caused the Big Bang to happen when it did?' and an apparent lack of awareness by both physicists and questioners that these are metaphysical questions but not necessarily irrelevant ones.
Wayfarer April 06, 2018 at 09:53 #169877
Quoting Joshs
According to this alternate perspective, any science , in any era, is always already a philosophical worldview , articulated via a particular vocabulary and methodology that marks it as science according to the conventions of that era.


:up:
ProcastinationTomorrow April 06, 2018 at 10:21 #169883
Reply to Cuthbert Agree with you entirely. Perhaps we should start up a separate discussion (if there isn't one already) on the principle of sufficient reason.
Harry Hindu April 06, 2018 at 11:00 #169887
The only difference between physics and metaphysics is that claims made by the physicists are falsifiable, while metaphysical claims are not. Eventually they both have to be compatible with each other and cannot contradict each other.
Metaphysician Undercover April 06, 2018 at 11:25 #169890
Quoting Joshs
Nelson Goodman recognized the dependence of the objects of science on subjective construction.
“If the composition of points out of lines or of lines out of points is conventional rather than factual, points and lines themselves are no less so. ... If we say that our sample space is a combination of points, or of lines, or of regions, or a combination of combinations of points, or lines, or regions, or a combination of all these together, or is a single lump, then since none is identical with any of the rest, we are giving one among countless alternative conflicting descriptions of what the space is. And so we may regard the disagreements as not about the facts but as due to differences in the conventions-adopted in organizing or describing the space. What, then, is the neutral fact or thing described in these different terms? Neither the space (a) as an undivided whole nor (b) as a combination of everything involved in the several accounts; for (a) and (b) are but two among the various ways of organizing it. But what is it that is so organized? When we strip off as layers of convention all differences among ways of describing it, what is left? The onion is peeled down to its empty core.”


Right, there are assumptions made about the nature of space, the nature of time, the nature of living beings, etc., which form the fundamental conventions that are used by science. These assumptions are the metaphysical principles which science relies on. When we apprehend these conventions as metaphysical principles rather than as brute facts, we see how metaphysics underlies science.
Streetlight April 06, 2018 at 11:50 #169892
The blog post is weird in that it acts as though it's exposing some hidden or esoteric aspect of science that scientists have been doing their best to keep secret for fear of embarrassment or something. Which would be interesting if it wasn't for the fact that scientists deal with possibility all the time, and that wrangling with possibility is incredibly run-of-the-mill for everyday work both in and out of the lab,

Not only in the example given, but also in modelling exercises, which aim to do nothing less than track possibilities among actual systems. One can also think of the relevance of statistical thinking in biology and thermodynamics, not to mention quantum physics. Hell, cosmology even creates entire toy universes to play with so that they can shed more light on how our universe works. Feynman's sum-over-paths method of measuring particles literally assumes that a particle travels along all possible paths to get to a destination. It does this by quite literally mathematizing possibility. The idea that 'science only concerns itself with the actual' seems bizarre to say the least, and seems to evince nothing other than a poor and unrecognizable conception of science shared by no actual scientists. To this degree the blog seems to be beating on a wide open door, or at least an imaginary one.

If there's a grain of truth in the blog post it's that the exact ontological standing of 'possibility' is often left untheorized, but for the simple reason that it doesn't really need to be. If a prediction comes out right, or your model correctly tracks the phenomenon under investigation, then you've done your work as a scientist. One can employ possibility without ontologizing it. At the very least the post reeks of the same kind of arrogance and one-upmanship that it so dislikes, and so is as much a part of the problem it tries to diagnose.
Moliere April 06, 2018 at 14:31 #169911
I believe there is no meaningful difference to be made between scientific and metaphysical beliefs.

That being said, I have to echo some of what StreetlightX says above. The blog post does come across as a bit odd. In particular...


This physical system has a kinetic energy, determined by the velocity and mass of the javelin, and a potential energy, fixed at any moment by the javelin’s height above the ground and its weight. The physical quantity known as the action of this system is defined by physicists in terms of changes in these two quantities of energy over specific periods of time. The Principle of Least Action requires precisely and only one thing: that the actual value for the action of this system during any such interval should be the smallest it could possibly take. In this particular case, this translates into the requirement that during any period of the javelin’s flight, out of all the possible paths between its initial and final location for that period, the javelin must follow the path that ensures the action of the system will be zero. As it turns out, only one path meets this requirement, and it is the one that Newton’s laws of motion describe. So, Newton’s laws follow from the Principle of Least Action.


is just a bad argument. There is no such thing as "the action of this system", and the Principle of Least Action is something the writer is importing here. There isn't anything to be said about paths in basic energetic modeling, only that energy is neither created nor destroyed. So Kinetic Energy is converted into Potential Energy as the javelin travels to its apex, and converted back into Kinetic Energy as it descends to the Earth where it is transferred to the Earth upon impact. Further, motion is different from energy in that it has a direction that is specified, and deals in forces rather than in energy.

If the principle of least action requies that the actual value for the action of the system during any interval should be the smallest, such reasoning doesn't enter in arguing where the javelin is going to fall or what is going to happen. The writer may see something of his principle in basic motion puzzles, but I sure don't. It just seems inserted in the middle of a text-book problem meant to explain the basics of motion without doing any argumentative work, and then is assumed to be required.

If that be the case then the rest -- possibility, actuality, paths -- are likewise not really part of the reasoning, since they all follow from this principle.

While it's the case that metaphysics is part and parcel to science -- or so I believe -- I'd say the writer here is way off, and hasn't really done the work necessary to understand the science.
_db April 06, 2018 at 17:46 #169935
Quoting ProcastinationTomorrow
but I do agree that scientists who think metaphysics should be buried are wrong.


It's not about getting rid of metaphysics. To do science, you must do metaphysics. But the metaphysics scientists need to operate is not something only a metaphysician can figure out. The problem is not that metaphysicians are being ignored - the problem is that some scientists are ignoring metaphysics, and some metaphysicians are ignoring science. The ideal scientist should also be a philosopher, and vice versa. So you have some scientists who think "Science" is a magical, perfect, self-contained intellectual project that can do no wrong and will ultimately figure everything out, "given enough time" - this is a problem.

Typically these sorts of scientists (or science-fanatics) are annoying and not wise. They make grandiose claims about the scope and potential of science, with little to no actual evidence to back it up. There's science, and then there's scientism, and the problem is that the latter is being appropriated into the former, so that science must now necessarily be scientistic. With the development of any kind of monism, such as scientism, comes the threat of dogmatism, so that intellectual progress is no longer open and free but now constrained within the metaphysical parameters that are informed by a select few charismatic individuals and their biases. These people can, upon realizing their position of authority in the public eye, use their platform to push unscientific and sometimes immoral public policies.

There is something unsettling to me about power-structures, and science isn't exempt. In my opinion, scientific realism might be justified, but anti-realism certainly provides a solid foundation for healthy relationship between science and the rest of society. It keeps scientists from getting too arrogant and presumptuous, and it helps secure the freedom of individuals to choose a worldview that fits their way of life.
Metaphysician Undercover April 06, 2018 at 21:17 #169964
Quoting StreetlightX
If a prediction comes out right, or your model correctly tracks the phenomenon under investigation, then you've done your work as a scientist.


This is not at all true. Thales predicted a solar eclipse. Following motions, and predicting what will be where at a future time, does not conclude the work of a scientist. The scientist's endeavour is to produce a complete understanding of the phenomenon. This attitude, that the work of science is simply to predict, is a philosophic illness, a mental laze.
jkg20 April 07, 2018 at 10:53 #170071
Reply to Moliere I agree the author of the article seems to be a bit of a crank (seems he or she thinks he or she can prove god exists for one thing). Having said that, I'm not sure I agree with your analysis of the argument concerned. As far as I understand the Principle of Least Action, at a general mathematical level it involves integration of differences between values over times, and requires that the integral be minimized. If a principle requires that some value be minimized, it allows that there might be all manner of possible values for that integral, and when applied to basic motion problems, those possible values do cash out as possible paths that particles or javelins or whatever might take. Thus the commitment to possibilia. The argument seems okay to me, at least structurally, although its individual premises might turn out to be untrue, or require other assumptions. For instance, I seem to recall reading that the Principle of Least Action can itself be deduced from Newton's Laws of Motion (which don't have ontological commitments to possiblia, just to instantaneous forces) so I guess there is a question of what laws or principles should be regarded as more basic. Of course, the Principle of Least Action is more general I presume, since as the cranky author says, its used in many different areas of physics.
jkg20 April 07, 2018 at 10:54 #170072
Moliere April 07, 2018 at 13:57 #170136
Reply to jkg20 I guess my thinking is this -- if you can model a physical system without reference to the principle of least action, then in what way must we be committed to whatever metaphysical commitments which come with it? With a system as simple as a javelin being through we certainly can do so -- and just because we can derive equations from some principle that does not then entail that we must do so.

I guess the example is just meant to be illustrative, though, rather than definitive. And yeah, it does seem more general. I had myself a bit of a wikipedia reading session after your reply to check myself and see if I was mistaken, and I was indeed ignorant of it being present in physics at a higher level. So I could be speaking a bit too ignorantly here, after all.

It seems, though, that the point could be made more simply. We don't need the most general form of physical theory to demonstrate that metaphysical commitments are part of physics. Interpretation of force, gravity, inertia, mass, and so forth fall squarely within the realm of metaphysics, by my lights.
jorndoe April 07, 2018 at 14:38 #170159
Suppose things were made of pixie dust.
The scientific methodologies wouldn't change a bit.

In (very) short, science is self-critical, bias-minimizing model ? evidence convergence, where tentative hypotheses can be derived from the models.
Evidence, observations, experimental results accumulate, and the models convergence thereupon.
The convergence protocols are what scientists do.

So, on that angle at least, only regularities are required, without which everything would be incomprehensible chaos anyway.
Moliere April 07, 2018 at 14:42 #170160
Quoting jorndoe
So, on that angle at least, only regularities are required, without which everything would be incomprehensible chaos anyway.


Regularities may be all that are required, but even specifying some belief in regularities is already a commitment. And if scientists said all things were made of pixie dust, rather than particles, then these would also be commitments. Since they are commitments about what exists, they are metaphysical commitments.

A commitment can be changed, of course, upon pain of further reasoning or new discoveries. We could just as well use "belief" for "commitment", I'd say.
jorndoe April 07, 2018 at 14:57 #170161
Quoting Moliere
And if scientists said all things were made of pixie dust, rather than particles, then these would also be commitments. Since they are commitments about what exists, they are metaphysical commitments.


Right.
There's a difference between merely that something exists (?) and what exactly something is (quiddity), though.
Shamelessly pointing over at an old post: ? and quiddity
In general, the sciences tend to suppose that something is, and then try to learn more about what it is.
That said, of course some make commitments to specific metaphysics about what exactly things are, but, on the angle above, the sciences don't really care much.
Moliere April 07, 2018 at 15:36 #170167
Reply to jorndoe I agree there's a difference between those two, but I don't know why you'd think science is restricted to one or the other.

How would a biologist work under such a regime? "We agree that yeast exist, but we do not characterize them" isn't exactly what microbiology looks like.
Moliere April 07, 2018 at 16:47 #170180
It might help, too, to note that beliefs of the form "does not exist" or "does not necessarily exist" would also count as metaphysics, in my view. So we might talk in terms of forces but believe there is no such entity, but it is a convenient shorthand for describing the behavior of fields. Or we might take an instrumentalist approach to scientific discourse and claim that while it works it does not speak of what exists, even while making what appear to be existential claims.

Perhaps you could say you are a sort of agnostic and say that all entities named by science may or may not exist, but even this sort of ploy seems to me to take a sort of skeptical stand towards metaphysics -- which is either a convenient opinion which suits one's feelings, in the absence of an argument, or a sort of belief with regards to the knowability of entities in the presence of an argument, and would count as a kind of commitment with respect to metaphysics because it deals with entities and our minds relation to said entities in such a case.

Unless science, in spite of appearances to the contrary which seem to make claims about what exists and how it exists, could be construed to somehow be about something else in actuality -- sort of like an error theory of science -- science talks about what does or does not exist, therefore is discussing metaphysical topics. And any argument which says science does not deal with entities would itself be a metaphysical thesis, so I don't see much escape from the charge of "doing metaphysics" here.

Not that there's anything wrong with that, by my lights. I don't think there's anything useful to be had by trying to separate the two. Science is just a bunch of arguments, in part empirical and in part more a priori. It's a hodge-podge of impurity interested in asking and answering questions, not some sort of regimented methodology followed with ritual precision to obtain the pure stuff of nature.
SophistiCat April 08, 2018 at 09:45 #170334
Reply to Moliere Science tends lead people to one of these views:

  • 1. Reductionism: There is one true ontology (usually assumed to be something like that of the Standard Model of particle physics), while the ontologies of other sciences are useful fictions. This is mostly favored by physicists and others with "physics envy" (like chemists ;)).2. Instrumentalism: All ontologies are useful fictions.


I would also add

  • 3. Pluralism: Ontologies are dependent on theories that posit them, and they are all real just to the extent to which their respective theories are taken seriously.
Wayfarer April 08, 2018 at 10:28 #170337
Quoting jorndoe
In general, the sciences tend to suppose that something is, and then try to learn more about what it is.


It’s more that modern science wished to start with assuming the ‘apodictic certainty of the testimony of the senses’ by first of all discarding the ‘fog of metaphysics’ [Bertrand Russell’s term] and beginning with what could be analytically and experimentally known and measured. And who could possible disagree with that, right? Galileo rolled two balls down an inclined plane and showed that their arrival was not dependent on their mass - thereby disproving scholastic philosophy once and for all, which was thrown out with Ptolemaic cosmology, right? What could be more obvious?
Moliere April 08, 2018 at 14:35 #170395
Reply to SophistiCat I'd probably fall closest to number 3. Seems about right to me.
T_Clark April 08, 2018 at 18:26 #170484
Quoting Wayfarer
On the other hand, there is a huge and highly charged debate going on in current physics and cosmology, as to whether string theory and the speculative multiverse that flows from it, is really a matter for science or not. On the Nay side are those who say that these ideas can never be falsified even in principle, as they concern matters which are by definition outside the universe. On the Yay side are those who say that, because of the compelling nature of the mathematics and the solutions that these models offer to many intractable problems, then such speculations should be regarded as within the ambit of science.


Sorry I came late to this discussion. I looked through the other posts. I don't think what I say will duplicate others, although several people have touched on issues discussed in this post.

What Wayfarer says, above, is something I've thought about a lot. It does seem to me that if something can't be falsifiable, even in theory, it's not science. It's either metaphysics or meaningless. On the other hand, if the mathematics and the solutions that these models offer solutions to many intractable problems, why isn't that an example of falsifiability?

Quoting darthbarracuda
Then, of course, there are the assumptions that other people do in fact exist, that there is actually a real, external world that continues to exist without our participation, that there are "laws" that are explicable mathematically, etc.


@tim wood steered me towards "An Essay on Metaphysics," by R.G. Collingwood. I really like it, at least partly because his definition of "metaphysics" is similar to mine, although different from many others on this forum and elsewhere. Here's what he says:

"Metaphysics is the attempt to find out what absolute presuppositions have been made by this or that person or group of persons, on this or that occasion or group of occasions, in the course of this or that piece of thinking."

Here's what he says about absolute propositions:

"An absolute presupposition is one which stands, relatively to all questions to which it is related, as a presupposition, never as an answer."

"Absolute presuppositions are not verifiable. This does not mean that we should like to verify them but are not able to; it means that the idea of verification is an idea which does not apply to them...."

Here are some statements I think are absolute presuppositions:

  • The outside world exists.
  • There is an objective reality.
  • Every event has a cause. There are no miracles. Causes are naturalistic.
  • Truth is the ultimate goal of science and philosophy.
  • The world behaves the same now as it did in the past and the same here as it does elsewhere in the universe.


Wayfarer April 08, 2018 at 21:07 #170536
Quoting T Clark
What Wayfarer says, above, is something I've thought about a lot. It does seem to me that if something can't be falsifiable, even in theory, it's not science. It's either metaphysics or meaningless. On the other hand, if the mathematics and the solutions that these models offer solutions to many intractable problems, why isn't that an example of falsifiability?


Popper devised the criterion of falsifiability to distinguish empirical hypotheses from speculative ideas that could not in principle be tested against some observation. Mathematics is a different matter as it concerns purely mathematical or logical facts.

As to why speculative mathematical theories such as string theory are scientific matters or not - obviously a highly vexed question. Have you heard of a book called Farewell to Reality, by Jim Baggott? It's a sceptical analysis of the current state of physics speculation by a physics-educated science writer. That and Peter Woit's book Not Even Wrong are both highly critical of string theory and its proponents.

I take issue with every one of your 'absolute presuppositions', as they're not actually part of the curriculum of metaphysics proper (especially #3). I think what you're doing there is conflating metaphysical naturalism with metaphysics proper. Metaphysical naturalism is the commitment of science to seeking natural explanations and causes, which is all well and good. However when that becomes a global statement about what is real, what kinds of causes exist, then you're no longer in the territory of metaphysical naturalism, but of metaphysics proper. You're making statements about 'the nature of reality' on the basis of naturalism. And that's susceptible to the 'metal detector' analogy that Feser gives in his criticism of 'scientism':


1. The predictive power and technological applications of the natural sciences are unparalleled by those of any other purported source of knowledge.

2. Therefore what science reveals to us is all that is real.

Compare:

1. Metal detectors have had far greater success in finding coins and other metallic objects in more places than any other method has.

2. Therefore what metal detectors reveal to us (e.g. coins, gold nuggets) are all that is real.

Metal detectors are keyed to those aspects of the natural world susceptible of detection via electromagnetic means (or whatever). But however well they perform this task -- indeed, even if they succeeded on every single occasion they were deployed -- it doesn't follow that there are not aspects of the natural world other than the ones they are sensitive to.



T_Clark April 08, 2018 at 21:17 #170539
Quoting Wayfarer
Popper devised the criterion of falsifiability to distinguish empirical hypotheses from speculative ideas that could not in principle be tested against some observation. Mathematics is a different matter as it concerns purely mathematical or logical facts.


I guess what I was trying to say is, if I can't directly observe a phenomenon, but it's existence explains things I can observe, which is what I thought you were describing, then it may be reasonable for me to infer it's existence.

Quoting Wayfarer
I think what you're doing there is conflating metaphysical naturalism with metaphysics proper.


Not sure I understand the distinction. Collingwood is talking about absolute presuppositions "made by this or that person or group of persons, on this or that occasion or group of occasions, in the course of this or that piece of thinking." I interpret this as similar to what I have said in previous discussions - metaphysical approaches are chosen based on usefulness, not some absolute correspondence with reality. As he says, "Absolute presuppositions are not verifiable."
Wayfarer April 08, 2018 at 21:26 #170542
Quoting T Clark
I guess what I was trying to say is, if I can't directly observe a phenomenon, but it's existence explains things I can observe, which is what I thought you were describing, then it may be reasonable for me to infer it's existence.


It sounds a simple principle - but what about 'bubble universes' or 'multiple worlds'? Is it 'reasonable' to posit the reality of those? That is the salient point here.

Quoting T Clark
Collingwood is talking about...


If Collingwood is writing from within the Western philosophical tradition, then he's talking in terms of Aristotelian metaphysics, which has a definite domain of discourse. Sure it's 'general' in the sense of being a 'philosophy of first principles', but at the same time, it articulates the issues using a particular kind of vocabulary and set of concepts.
T_Clark April 08, 2018 at 22:34 #170557
Quoting Wayfarer
It sounds a simple principle - but what about 'bubble universes' or 'multiple worlds'? Is it 'reasonable' to posit the reality of those? That is the salient point here.


Actually, the bubble universes was what set me off down this path. If I understood him correctly, @apokrisis was talking about them as an effect of one current understanding of inflation during, or before, or whatever, the big bang. If a phenomenon is required in order to understand something that is observable, even though it isn't, then it seems to me it meets the requirement as suitable for scientific evaluation.

Quoting Wayfarer
If Collingwood is writing from within the Western philosophical tradition, then he's talking in terms of Aristotelian metaphysics, which has a definite domain of discourse. Sure it's 'general' in the sense of being a 'philosophy of first principles', but at the same time, it articulates the issues using a particular kind of vocabulary and set of concepts.


Collingwood starts out talking about Aristotle, but it doesn't seem that hard to understand what he is trying to say. Unless I am misunderstanding something, his statements speak for themselves. I'll go back and read again.
T_Clark April 08, 2018 at 22:53 #170563
Reply to Wayfarer

Just to be clear, I have a lot of confidence in the way you see things. It's been a big help to me in the past. That makes me want to go back and re-examine what I'm saying.
apokrisis April 09, 2018 at 00:04 #170591
Quoting SophistiCat
3. Pluralism: Ontologies are dependent on theories that posit them, and they are all real just to the extent to which their respective theories are taken seriously.


That seems question begging about how you would define "real" here. How does it not wind up sounding idealist or subjective - that is, anti-realist?

And an even greater difficulty. The least action principle is an example of how science does appear to discover a unity, rather than a pluralism, at the deepest ontic level.

You can try any theory you like ... but the historical evidence is that it needs to be based on the least action principle with its focus on closure and symmetry.



Wayfarer April 09, 2018 at 00:22 #170601
Reply to T ClarkVery kind of you to say so. I will see if I can find a bit of time to read that Collingwood essay, it has been recommended by quite a few posters.
SophistiCat April 09, 2018 at 07:39 #170644
Quoting apokrisis
That seems question begging about how you would define "real" here. How does it not wind up sounding idealist or subjective - that is, anti-realist?


Well, I am not too concerned with how this sounds, but what question is being begged here?

Quoting apokrisis
And an even greater difficulty. The least action principle is an example of how science does appear to discover a unity, rather than a pluralism, at the deepest ontic level.


That to me suggests a structural relationship between theories. One is tempted to conclude that what accounts for this common trope is that in their different ways these theories all get a hold on the same truth. But one should always keep a bit of wary skepticism and not be totally seduced by theoretical elegance. That way lies dogmatism.
apokrisis April 09, 2018 at 11:47 #170665
Reply to SophistiCat Probably just simpler to say science believes there is ontically one world, but epistemically any number of models of it.

So instrumentalism and pluralism would be the same thing I would suggest.

You may have been making the point that every model advances its own ontic commitments. They talk of “real” entities like temperature or charge. But that wasn’t clear, and would still be pragmatism anyway.
gurugeorge April 09, 2018 at 20:21 #170732
Quoting ProcastinationTomorrow
what they are doing commits them to nothing other than constructing models


Even that implies a fair amount of metaphysics, I think. Who or what are "they", what is a "commitment", what is "construction", what is a "model"?

It's not really possible to think at all without taking a good deal for granted, and actually what's taken for granted is a bunch of fairly boring stuff that most people agree with and that comports with common sense.

However, one understand what those scientists mean: they mean they're not committing themselves to anything particularly bizarre or unusual.
SophistiCat April 09, 2018 at 20:27 #170733
Reply to apokrisis That's a fair point. I guess I am just not very serious about ontology: I am more interested to know what the world is like than what "stuff" it is made from or what "things" it ought to be parsed into - which puts me more on the side of instrumentalists and pragmatists. But I am also on the side of common sense and natural language in wanting to say that yes, there are chairs and cats and temperature and charge. That's just what "existence" means to us.