Principle of Sufficient Reason (PSR)

The Principle of Sufficient Reason is a powerful and controversial philosophical principle stipulating that everything must have a reason or cause. This simple demand for thoroughgoing intelligibility yields some of the boldest and most challenging theses in the history of metaphysics and epistemology. In this entry we begin with explaining the Principle, and then turn to the history of the debates around it.

Principle of Sufficient Reason

I think it would be a shame if a discussion over PSR was embedded deep in some other thread somewhere. So here’s hoping Erik and KN will take up any discussion around it here in this thread. (Yes, you’re not just talking to each other.)

But I’ll start by taking the first shot as is my right having created the OP. 🙂 I think there’s a more fundamental disagreement between Erik and KN than the PSR, and that would be over the very possibility of metaphysics itself. Or I could be all wet!

Please discuss. Thank you.

138 thoughts on “Principle of Sufficient Reason (PSR)

  1. You are applying a utilitarian rule, which I approve of. But utilitarianism is rule of thumb. Your underlying principle is that what works is true.

  2. Erik: I disagree profoundly. I happen to be one of those people to whom primary schools physics made hardly any sense, but as soon as quantum physics was introduced, I knew immediately what was going on and regretted all the years wasted on Newtonianism.

    A specific example would be helpful. What logical axioms or intuitions does QM disprove? E.g. does the double slit experiment disprove (or call to doubt) the law of excluded middle? If yes, how?

    A single electron interfering with itself (“going through both slits at once”) was the start for the puzzles of QM for me. Or if that seems reasonable to you, try delayed choice quantum_eraser experiments.

    Neils Bohr: “For those who are not shocked when they first come across quantum theory cannot possibly have understood it.”

    Putnam thought at one time that QM broke standard logic, but I believe he changed his mind. Or maybe he decided that proposition was neither true nor false.

    However, it is true that QM has been axiomitized; or at least the formalism for prediction with QM has been.

    I’m unsure about your reference to Newton. Usually it is Einstein and relativity that are seen as ending Newton. What role did you have in mind for QM?

  3. I am not arguing that QM overturns logic. Just that it overturns assumptions. The nature of causation is one of those assumptions.

    When you try to reason about the beginning of existence using conventional assumptions about time and causation, you are lost.

  4. Erik: Given that we are part of reality, then the things we have/do reflect the nature of (part of) reality, right?

    That’s about the only sentence in that post that I agree with. Pretty much all of the rest of it seems wrong to me. But I don’t have the patience to go through it line by line the way KN does. You can just tick your remarks off one by one and say to yourself, “Walto says he doesn’t agree with this: I don’t know/(or I understand) why” “Walto says he doesn’t agree with that: I don’t know/(or I understand) why” Etc.

    My sense is that you’re much better off continuing with KN, who has a lot more patience than I do for posts that are so redolent with pseudo-argumentation.

  5. petrushka:
    I am not arguing that QM overturns logic. Just that it overturns assumptions. The nature of causation is one of those assumptions.

    Not sure if this was for me, but I wasn’t commenting on things you’ve said, which I interpret as meaning that no one would have ever deduced QM from pre-set axioms and rational argument before the experiments and known puzzles (eg UV catastrophe). The contemporary experts found the results of these early experiments deeply puzzling and non-intuitive.

    I was replying to my reading of Erik looking for aspects of QM that were unintuitive or that spoke to traditional logic. Although I am not sure if he was limiting his intuitions to those about logic or whether intuitions about experimental results were included. I assumed the latter.

  6. FWIW, I continue to find QM hard to swallow. I think that’s what makes Bohm so congenial to me–in spite of nobody in the field agreeing with him.

    I don’t say this to suggest that everybody’s wrong and I’m right–quite the contrary. I only mention it to point out that I agree with (I think) both Bruce and petrushka, that “spooky causation” is contrary to my intuitions–just as it was to Einstein’s.

  7. walto:
    FWIW, I continue to find QM hard to swallow.I think that’s what makes Bohm so congenial to me–in spite of nobody in the field agreeing with him.

    It does have a smallish group of supporters that are working on it but I think many would say it has irreparable limitations.

    It is non-local; the instantaneous correlations (but not causes) still happen.

    So it is of no help if you are looking for a Humean world a la Lewis: “all there is to the world is a vast mosaic of local matters of particular fact; all else supervenes on that” (from SEP article on supervenience).

    AFAIK, that cannot be, now that we have results of Bell experiments (unless one takes one of the escape clauses like superdeterminism). Here for more.

  8. BruceS,

    As I understand it, one major drawback of Bohmian mechanics is that it has no equivalent to quantum field theory, which underpins our theory of quantum electrodynamics (which unifies the electromagnetic and weak forces).

    That said, Bohmian mechanics, being both non-local and deterministic, also appeals to my Spinozism. But I don’t think that aligning with one’s philosophical prejudices is a good reason for preferring one empirical theory over another.

  9. BruceS: It is non-local; the instantaneous correlations (but not causes) still happen.

    So it is of no help if you are looking for a Humean world a la Lewis: “all there is to the world is a vast mosaic of local matters of particular fact; all else supervenes on that” (from SEP article on supervenience).

    AFAIK, that cannot be, now that we have results of Bell experiments (unless one takes one of the escape clauses like superdeterminism)

    I actually find Bohm and de Broglie more congenial than Hume or Lewis. Remember, I was a Spinozist in my ill-spent youth.

    BWTHDIK?

  10. Kantian Naturalist: I don’t think that aligning with one’s philosophical prejudices is a good reason for preferring one empirical theory over another.

    Too true. 🙁

  11. Kantian Naturalist:

    As I understand it, one major drawback of Bohmian mechanics is that it has no equivalent to quantum field theory,

    I’ve read similar. But its supporters are working on it. The article in Wiki discusses.

    Unfortunately, Sophisticat does not post here anymore; I’m sure he could help.
    He still posts in other places if people are interesting in QM, intuitions, consciousness, etc as understood by someone who knows what he is talking about.

    Speaking about other places, Evan Thompson is posting on his latest book at Brains blog. He was also interviewed about it a few months ago on New Books in Philosophy.

  12. Nice to hear news of sophisticat. I enjoyed (and learned from) his posts. Sorry he disappeared from these parts.

  13. Neil Rickert:
    I readily accept the principle: Everything has a pseudo-explanation. The world is full of pseudo-explanations.

    All you have done is show that there is at least one pseudo-explanation.

  14. RodW: I think saying the universe exists or came into existence is nonsensical in a way because we’re lumping it together with objects within the universe.

    Hi RodW,

    But what if the universe just is that of which it is composed? It is a composite, and it is made up of exactly those sorts of things that come into a go out of being. Would you say that we cannot reason about the body because it is composed of parts?

  15. walto: I don’t say this to suggest that everybody’s wrong and I’m right

    Indeed. That goes without saying. 🙂

  16. Mung: But what if the universe just is that of which it is composed? It is a composite, and it is made up of exactly those sorts of things that come into a go out of being. Would you say that we cannot reason about the body because it is composed of parts?

    Interesting point, but I wonder: Firstly, might cosmology gives us any grounds for denying that the universe is a composite (why isn’t the universe a simple, and its parts simply different aspects of it rather than different self-subsisting entities?). Secondly, I think that RodW is making the cogent point that our common-sense intuitions about objects in space and time don’t necessarily scale up when it comes to thinking carefully about the very fabric of space and time itself.

    A related point can be made in terms of informational closure. Open systems are not just thermodynamically but also informationally open, which is why we can take a measurement of the system from outside of it. But is the universe as a whole informationally closed? That seems to depend on whether or not the universe “began” with a singularity. If it did, then the universe is informationally closed (if I’m getting my physics right). That would mean that no claim about what is “outside” the universe could be empirically verified — there is no measurement that can be taken outside of the universe as a whole.

    That doesn’t mean that there are no good arguments for or against theism or atheism, but it does have the somewhat interesting consequence that there is no scientific basis for either theism or atheism.

  17. Neil, your claim was that there appear to be uncaused events in QM. This is, presumably, your basis for believing the PSR is false.

    I see it [PSR] as false as a principle (there appear to be violations in QM)

    Please show or explain your logic, and try not to beg the question.

    There was nothing mysterious about my posts in response to your introduction of QM and nothing mysterious about your lack of response. You can’t LOGICALLY get where you got from the place you started. Your arguments are non-sequiturs.

  18. Mung: Neil, your claim was that there appear to be uncaused events in QM. This is, presumably, your basis for believing the PSR is false.

    I see it [PSR] as false as a principle (there appear to be violations in QM)

    Please show or explain your logic, and try not to beg the question.

    I formed an opinion based on evidence. I don’t understand what it is that you are questioning about that?

  19. It’s really simple Neil. You didn’t form an opinion based on evidence. You did present an argument which you’ve subsequently been unable to support with anything more that to say that you were just offering an opinion.

    If that is all you have to offer the PSR is in no danger.

  20. Kantian Naturalist: Interesting point, but I wonder:

    I think I owe it to Geach from the chapter on Aquinas in Three Philosophers. I’ll have to check.

    Firstly, might cosmology gives us any grounds for denying that the universe is a composite (why isn’t the universe a simple, and its parts simply different aspects of it rather than different self-subsisting entities?).

    Perhaps, but not if you’re Aristotelian. 😉 Or a Thomist.

    One could deny that the universe is a whole composed of parts, but that would seem to go against common sense and I can’t see how science could answer the question in favor of that proposition.

    If you wish to say that the universe has no parts then surely you should use some other word than parts. ok, it has no parts, but it has … “aspects”

    I’m not saying the idea is too far fetched, for this is what the Doctrine of Divine Simplicity is all about. God is utterly simple and without parts. And yet we speak of various “attributes” of God.

    So in what you are proposing the “entities” that we see coming into existence and going out of existence, as part of our normal experience, are not “parts” of the universe but rather are aspects of a single simple entity that has no parts. So then the question naturally arises, do these “aspects” come into and go out of existence?

    [btw. The entire argument we’re talking about rejects the idea that these entities subsist of themselves, so your “rather than” is slightly misguided.]

    So to cap this particular line, you would deny the empirical premise of the classical argument, that things really do come into existence and go out of existence?

  21. Mung: You didn’t form an opinion based on evidence.

    Of course I did.

    You did present an argument which you’ve subsequently been unable to support with anything more that to say that you were just offering an opinion.

    I was not trying to persuade anyone to agree with me. Why would you think there was an argument?

  22. Kantian Naturalist:
    That would mean that no claim about what is “outside” the universe could be empirically verified — there is no measurement that can be taken outside of the universe as a whole.

    Not sure I follow, but I’ll take a stab at it. You’re opening up an entire other can of worms. 🙂

    Even a thermodynamically closed system is informationally “open.”

    Any measurement requires the establishment of the system and the environment and this requires an observer.

    Any measurement from “outside” the universe would requite an observer “outside” the universe. So such a measurement could be empirically verified.

  23. Mung: You didn’t form an opinion based on evidence.

    Neil Rickert: Of course I did.

    If you had, you could have presented and explained it, which you have so far failed to do. Will you now do so?

    I was not trying to persuade anyone to agree with me.Why would you think there was an argument?

    Because you stated that you believe the PSR to be false based upon some supposed evidence which you will no doubt present shortly.

    One could assume that you had some reason for your belief based upon some premise arrived at by some sort of logical progression, You know, an argument.

    Your position seems to be that you believe NOT X, given Y, but that no one reading your comments ought to take this as any argument against X because you’re not making any argument but merely stating an opinion, but your opinion is actually based on evidence.

    You don’t have any evidence, and you don’t have any argument. The PSR is not in any danger from the likes of Neil Rickert.

  24. Mung: Any measurement from “outside” the universe would requite an observer “outside” the universe. So such a measurement could be empirically verified.

    If there were such a hypothetical observer, sure — but since the existence of precisely that kind of hypothetical observer is unverifiable to us, its existence or non-existence is irrelevant to all descriptive claims that we can (physically) possibly consider.

  25. Neil Rickert: You are not making sense.

    The difference here is that I am at least trying to make sense and you are not even trying.

    You were simply offering an opinion, it was not based on any facts or evidence, and you weren’t offering any reason why anyone should believe you, what you were saying was not offered in the way of any argument, it was just your opinion. Baseless. Opinion.

    Do you disagree with my presentation of your position?

  26. Mung: Do you disagree with my presentation of your position?

    Of course.

    You started the thread.

    You asked for opinions:

    Please discuss. Thank you.

    And now you seem to object that I offered an opinion.

    I don’t get it. I haven’t offered any logical argument, because I don’t think such an argument is possible. I don’t see how it could ever be anything other than opinion.

    I really don’t understand why you have been dogging me about this.

  27. BruceS:
    A single electron interfering with itself (“going through both slits at once”) was thestart for the puzzles of QM for me.Or if that seems reasonable to you, try delayed choice quantum_eraser experiments.

    The conventional double-slit experiment shows that photons have dual nature, that of both particle and wave. Detection makes photons drop the wave aspect and assume the nature of a particle. In macroscale, this is similar to water, which can appear as liquid on ordinary conditions, but as ice on other conditions.

    The delayed choice quantum eraser experiment shows that the same observation concerning photons applies across entanglement. Provided that entanglement is real, whenever an entangled photon is detected to be something, its other pair should correspond to that detection. The delayed choice quantum eraser experiment shows entanglement to be real and that entanglement applies across space and time.

    Entanglement is not a causal phenomenon in that one event causes the next event. (There’s no retrocausality). Entanglement is a correlative or compensatory phenomenon (as per the principle of complementarity), like mirror effect or shadow effect. Your mirror image or shadow always does what you do, without fail. You cannot run faster than your shadow or outtrick your mirror image in any way. Entanglement is a similar phenomenon. (I’m not saying I know exactly the mechanics of light. I’m just saying that it’s not unique. Whatever phenomena we might encounter, there are always other analogical phenomena they can be compared to. If there weren’t, we couldn’t even label the new discovery a ‘phenomenon’.)

    I have my doubts also concerning the way general relativity is interpreted. I don’t think it makes sense to say that the speed of light is the same for all observers independent of the speed of observers (because this poses the question: In relation to what is this speed of light? Faster than what?) or that time differs relative to the gravity and speed of observers (because this goes against the very definition of time). I think that the speed of light is really not a speed, but a ground property of light as substance. Physical light is really differences in the visual field: One place has one visual intensity, another place has another visual intensity, and that’s how we see something, anything. Without this difference, there’s no vision. So, saying that the speed of light is the same for all observers independent of the speed of observers is to say that the essential correlation of light and vision remains the same.

    To say that time slows down is a similar flaw like to say that space moves. Space cannot move and time cannot slow down – by definition! Measurement of time may slow down and perception of space may shift. If time is defined as the difference between one objective instance and the next, then it follows that at the multiplication of instances there’s more difference, “more time to measure” so to say. And this has been found true for clocks. When a clock is sped up in relation to another clock, the sped-up clock has more objective instances to follow through and it accordingly slows down. Similar thing with space perception. When we have walls around us and the walls approach, we say “Space is getting smaller.” In reality, space is not getting smaller – the perception of space does.

    Light is that which makes objects visible. So, there must be three things: An object, an observer, and they both must be placed “in the same light” so to say. Returning to the delayed choice quantum eraser experiment, what the experiment really does is to objectify that which makes objects visible. It takes that which makes objects visible and makes an object out of it. To see the resulting object, we need “more light”, but “normal vision” properly functions when the object and the observer are both “in the same light”. The experiment negates “same light” and thus it negates “normal vision”, resulting in the phenomenon called quantum entanglement, which is a form of… Hmm, I remember I once read an article about this. Here http://www.thomist.org/jourl/1999/Jan%20A%20Smith.htm As this author calls it, quantum experiments result in a “bifurcationist point of view”. A quote, “Quantum paradox, it appears, is Nature’s way of repudiating a spurious philosophy.” Which I agree with. I’m not a Thomist myself, but they have said some things more succinctly than I can.

    BruceS:
    Neils Bohr: “For those who are not shocked when they first come across quantum theory cannot possibly have understood it.”

    I’m unsure about your reference to Newton.Usually it is Einstein and relativity that are seen as ending Newton.What role did you have in mind for QM?

    In my school, we had to swallow Newton throughout. Einstein and QM were only briefly touched in the final year. And yes, it shocked me that physics can actually make sense and even provide enlightenment. It was a drastically different experience.

    petrushka:
    I am not arguing that QM overturns logic. Just that it overturns assumptions. The nature of causation is one of those assumptions.

    When you try to reason about the beginning of existence using conventional assumptions about time and causation, you are lost.

    When people say QM is counterintuitive or, more strongly, it “disproves logic”, in my opinion they don’t know what they are saying.

    Assumptions are one thing, intuition is another. Also, the nature of time and causation is one thing, logic is another thing. QM may overturn assumptions about time and causation, like general relativity twisted assumptions about space, but none of this disproved logic and never will.

    It works the other way round: When you arrive at illogical conclusions (and I mean illogical, to do with logic, e.g. when you end up doubting the law of excluded middle or embracing infinite regress) then it’s an unmistakable sign that you are intepreting the observation in a wrong way. Having a paradox means you have no solution. Only logical explanations (distinct from confirming prior assumptions) count as possible explanations.

    Quantum paradoxes are Zeno’s paradoxes vol.2. They are solved by proper definitional dialectics, not by experimenting more with Achilles and the turtle.

  28. Erik: When a clock is sped up in relation to another clock, the sped-up clock has more objective instances to follow through and it accordingly slows down.

    Here it would have been appropriate to mention the Doppler effect. It’s a direct analogy.

  29. Erik: Entanglement is a correlative or compensatory phenomenon (as per the principle of complementarity), like mirror effect or shadow effect. Your mirror image or shadow always does what you do, without fail.

    Except that people and light DO cause shadows. In that case there’s (one-way) causality. So It doesn’t seem to me to be a great analogy.

    Also the properties of light pursuant to special relativity have nothing at all to do with vision.

  30. Logic is fine but there are no axiomatic truths about physical reality. There are no unassailable starting points for reasoning about the beginning of the universe.

  31. Mung: I think I owe it to Geach from the chapter on Aquinas in Three Philosophers. I’ll have to check.

    Perhaps, but not if you’re Aristotelian. 😉 Or a Thomist.

    One could deny that the universe is a whole composed of parts, but that would seem to go against common sense and I can’t see how science could answer the question in favor of that proposition.

    If you wish to say that the universe has no parts then surely you should use some other word than parts. ok, it has no parts, but it has… “aspects”

    I’m not saying the idea is too far fetched, for this is what the Doctrine of Divine Simplicity is all about. God is utterly simple and without parts. And yet we speak of various “attributes” of God.

    So in what you are proposing the “entities” that we see coming into existence and going out of existence, as part of our normal experience, are not “parts” of the universe but rather are aspects of a single simple entity that has no parts. So then the question naturally arises, do these “aspects” come into and go out of existence?

    [btw. The entire argument we’re talking about rejects the idea that these entities subsist of themselves, so your “rather than” is slightly misguided.]

    So to cap this particular line, you would deny the empirical premise of the classical argument, that things really do come into existence and go out of existence?

    This (nice) post reminds me a lot of my Spinoza studies. Spinoza called “modes” what you refer to above as “aspects.” They’ve been likened to ripples in water in that they can have no existence apart from that in which they participate.Spinoza has a lot to say about mereology (parts and wholes) too. One of the chapters of my thesis was about Spinoza and Cantor. It’s fun stuff.

    BTW, if you’re still buying philosophy books, one I particularly liked back then was Aeternitas by the Spinoza fanatic, A.E. Hallett. Hallett wrote only about Spinoza during his career. Three books, I believe, and a few papers as well. For Aeternitas he also painted Spinoza’s portrait. His work suffers from the Hegelianism of his day, I think, but it’s weirdly complex and enjoyable. In another thread, I mentioned Broad writing a book on McTaggart and time. Broad also wrote a series of papers on Aeternitas. Hallett’s stuff is not particularly scholarly or even always accurate, and he’s probably not read much anymore, but his love for his subject shines through.

  32. walto: I actually find Bohm and de Broglie more congenial than Hume or Lewis.

    I’m curious as to why.

    I guess it’s re-assuring that Bohm makes position really real, but to do that I understand he needs a “pilot wave”, which does not exist in our universe, but only in a mathematical configuration space. Yet it controls what happens in our spatio-temporal reality.

  33. Erik:

    Thanks for the long reply. Rather than reply to detailed points, I’ll just suggest a few ideas related to points you make:

    Double Slit Intuitions
    My naive view was that interference was a mass effect: electrons travelled in waves which interfered. But, even if a single electron only is allowed in the double slit apparatus, an interference pattern still builds up if both slits are open and does not if one slit is closed. Further, roughly speaking, we can close one slit after the electron must have passed through, and the pattern still disappears (delayed choice). Again, roughly speaking, we can observe partial, limited information about which slit the electron passed through, and we will then see a mathematically predicable partial removal of interference. Those facts are highly non-intuitive to me.

    Entanglement and Bell Inequalities
    It can be misleading to use ordinary conceptions of correlation. Bell referred to this by his Prof Bertlmann’s socks story. Suppose we know the prof always wears a red sock and a white sock; if we see one leg with a red sock, we know without looking the other must be red. But the correlation implied by violation of the Bell inequalities is subtler. To understand how, one needs to work through some simple math.

    Special Relativity, Speed of Light, “Objective Instants”
    You are correct that scientifically working with concepts like the “speed of light ” requires operational definitions. Einstein used reference frames as the start: 3D grids moving relative to each other, where each frame separately has synchronized clocks at each point in the grid. Both frames measure the same speed of light; but our intuition from everyday movement is that two observers moving relative to each other will measure a different speed for some third entity. Measurement of light’s speed can be carried out and Einstein’s postulate has been verified.

    The paradoxes of SR involve both time and length changes in separate frames, like the barn pole paradox. Usually they can be understood by recognizing that SR says there is no universal simultaneity: instead, simultaneous events can only be defined for a single frame. That’s one key difference from Newton’s ideas of time. There is no absolute time in Newton’s sense.

    When you speak of different “objective instances” for different observers, that sounds Newtonian to me. But such a concept of time is not used for successfully predicting experimental results, so I look elsewhere for a conceptual scheme I would find useful.

    Saying it is just perception of time that changes does not work for me. For if two clocks are synchronized, then travel in different frames, then are brought back together, their readings will differ. In fact, GPS as configured on satellites and receivers, would not work without this fact. I don’t see how it can be called only a perception.

    Thomist QM
    I had nor realized there was a Thomist view of the metaphysics of QM. For me, anyone who wants to work on metaphysics in QM needs the equivalent of a double PhD in physics and philosophy; people like Wallace, Maudlin, Albert. Further, I doubt that the detailed metaphysical implications of QM can be cogently done in natural language. The analysis needs to involve math, for QM is only expressible in detail in the mathematical formalism.

  34. BruceS: Further, I doubt that the detailed metaphysical implications of QM can be cogently done in natural language. The analysis needs to involve math, for QM is only expressible in detail in the mathematical formalism.

    It’s done all the time, but it’s just woo.

  35. Mung: Hi RodW,
    But what if the universe just is that of which it is composed? It is a composite, and it is made up of exactly those sorts of things that come into a go out of being.

    Hi Mung,

    I would say that ‘whole’ and ‘parts’ are again ways of organizing reality that have been programmed into us because we live within the universe ( come to think of it ‘within’ might not be a great description) and probably shouldn’t be ascribed to the universe as a whole

    I’m not trying to be mystical and obscure; I’ve heard Carroll and Krause say similar things in lectures and debates

  36. walto: Except that people and light DO cause shadows. In that case there’s (one-way) causality.So It doesn’t seem to me to be a great analogy.

    Where we draw the line between causality and correlation (or complementarity) depends on how deeply hooked we are on Aristotelian definition of causality. For Aristotle, it makes sense to say “final cause” i.e. that towards which the thing moves is somehow a cause for the thing. In Aristotle’s system there are causes throughout, no complementarity at all. I wouldn’t be surprised if for some A-T philosopher retrocausality (an effect that temporally precedes its cause) sounds plausible or explanatory. Not to me.

    Here I’d draw the line between causality and complementarity by positing that non-entities (insubstantial things) are uncaused. If we suppose that light on an object causes (in the sense of “brings into existence”) the shadow behind the object, then lack of light should destroy the shadow. But there are no pieces left behind by the shadow’s destruction – the shadow is insubstantial. Moreover, lack of light actually extends the shadow. And darkness is all-shadow, so to speak.

    The shadow itself just is a patch of reduced light on a surface next to a greater intensity of light on the same surface. So, since the shadow just is lack of light, is it appropriate to say that it’s caused by light (or by lack of it)? Wouldn’t it be like saying that a shorn sheep is caused by lack of wool?

    So, shadow is not caused by, but is identical to a certain shape of blocked light on a surface. A person’s mirror image is properly identical to the person’s reflection, not caused by it. And similarly, entangled photons in the experiment are identical to their property of entanglement. Whatever happens to one, also happens to another, because this is what entanglement means. If entanglement is real, then this is what we should expect by definition.

    The deeper question is perhaps, why is there entanglement on quantum level? To me it’s a question similar to, why are there shadows on the scale of our common perception? If the answer to the latter question is that shadows are identical to certain appearance of (lack of) light on surfaces, then the answer to the former question, if my analogy applies, is that entanglement is identical to a particular division in quantum substance where the division cannot create two separate entities, but only entangled ones.

    Quantum level is where cutting a supposed entity doesn’t create two separate entities, but complementary ones, like putting a whole-wall mirror in the room “causes” another room. There are no real divisions on that level. It’s like bird tracks in the sky or lines in water.

    Atom originally meant indivisible. Ancients always were onto something big.

    walto:
    Also the properties of light pursuant to special relativity have nothing at all to do with vision.

    Yeah, like observations have nothing to do with the observer and experiments have nothing to do with the experimenter…

  37. BruceS: I’m curious as to why.

    I guess it’s re-assuring that Bohm makes position really real, but to do that I understand he needs a “pilot wave”, which does not exist in our universe, but only in a mathematical configuration space.Yet it controls what happens in our spatio-temporal reality.

    Dunno, I guess it’s that, unlike Erik here, who by the time he was in high school, and without studying physics at all, understood Heisenberg to be a somewhat confused adherent of some scholastic he enjoys, I find “spooky action at a distance” bewildering, and find the idea of “implicate order” comforting.

    Also, unlike Erik, however, I don’t confuse my comfort with an actual argument for anything.

  38. Erik: Where we draw the line between causality and correlation (or complementarity) depends on how deeply hooked we are on Aristotelian definition of causality. For Aristotle, it makes sense to say “final cause” i.e. that towards which the thing moves is somehow a cause for the thing. In Aristotle’s system there are causes throughout, no complementarity at all. I wouldn’t be surprised if for some A-T philosopher retrocausality (an effect that temporally precedes its cause) sounds plausible or explanatory. Not to me.

    Here I’d draw the line between causality and complementarity by positing that non-entities (insubstantial things) are uncaused. If we suppose that light on an object causes (in the sense of “brings into existence”) the shadow behind the object, then lack of light should destroy the shadow. But there are no pieces left behind by the shadow’s destruction – the shadow is insubstantial. Moreover, lack of light actually extends the shadow. And darkness is all-shadow, so to speak.

    The shadow itself just is a patch of reduced light on a surface next to a greater intensity of light on the same surface. So, since the shadow just is lack of light, is it appropriate to say that it’s caused by light (or by lack of it)? Wouldn’t it be like saying that a shorn sheep is caused by lack of wool?

    So, shadow is not caused by, but is identical to a certain shape of blocked light on a surface. A person’s mirror image is properly identical to the person’s reflection, not caused by it. And similarly, entangled photons in the experiment are identical to their property of entanglement. Whatever happens to one, also happens to another, because this is what entanglement means. If entanglement is real, then this is what we should expect by definition.

    The deeper question is perhaps, why is there entanglement on quantum level? To me it’s a question similar to, why are there shadows on the scale of our common perception? If the answer to the latter question is that shadows are identical to certain appearance of (lack of) light on surfaces, then the answer to the former question, if my analogy applies, is that entanglement is identical to a particular division in quantum substance where the division cannot create two separate entities, but only entangled ones.

    Quantum level is where cutting a supposed entity doesn’t create two separate entities, but complementary ones, like putting a whole-wall mirror in the room “causes” another room. There are no real divisions on that level. It’s like bird tracks in the sky or lines in water.

    Atom originally meant indivisible. Ancients always were onto something big.

    Yeah, like observations have nothing to do with the observer and experiments have nothing to do with the experimenter…

    The shorn sheep analogy is actually worse than the original shadow analogy. Absences often have causes: in the case of the sheep it was some clippers. In the case of the shadow it is light waves and objects impermeable by them. The idea that you can correct or interpret scientific theories by the use of these lame analogies is actually kind of amusing.

    Similarly, whether or not observers have anything to do with observations is a red herring. The special theory of relativity has nothing to do with vision. Light would exist without vision.

    These musings of yours are just a matter of you spinning ridiculous webs that have nothing to do with science or even philosophy. I take it they provide some sort of comfort or enjoyment for you. So that’s nice, anyhow.

  39. walto: D I find “spooky action at a distance” bewildering, and find the idea of “implicate order” comforting.

    OK, and probably you are joking, but just in case “spooky action at a distance” (entanglement) is what pilot waves and the implicate order are both involved in enabling.

  40. If you have to have a cartoon materialist, it would at least involve someone who thinks that “objects” exist in the conventional, intuitive sense.

    I’m not denying the existence of real objects, but I am denying that we can reason about first causes using intuitive assumptions about matter and causation.

  41. BruceS: OK, and probably you are joking, but just in case“spooky action at a distance” (entanglement)is what pilot waves and the implicate order are both involved in enabling.

    No, I don’t agree with that assessment. I’d say the opposite–that pilot waves and Bohm’s “implicate order” make possible the reinstatement of non-spooky causation. The “distance” is, in a sense, eliminated.

  42. walto: The shorn sheep analogy is actually worse than the original shadow analogy.Absences often have causes: in the case of the sheep it was some clippers.

    Except that the point of the analogy was to say that the absence (of light or of wool) is not the cause of the effect, but it is the effect itself. Positing causes where there’s only correlation is one of the reasons why I’m not Aristotelian.

    walto:
    Similarly, whether or not observers have anything to do with observations is a red herring.

    Indeed, I was wondering why you introduced it. Now you gave it a name.

    Seriously, if you followed through consistently with your idea that (absence of) light is the cause of shadows, then it should not be a contentious matter to you that observers are causes of observations.

    ETA: Wrong framing of the race of Acchilles and the turtle is how Zeno got one of his paradoxes. Similarly, quantum paradoxes are due to fallacies of framing and naming. No other reason.

  43. Erik: Except that the point of the analogy was to say that the absence (of light or of wool) is not the cause of the effect, but it is the effect itself. Positing causes where there’s only correlation is one of the reasons why I’m not Aristotelian.

    Actually *I* was the one who pointed out that your original analogy to entanglement was bad because shadows ARE effects of causes. So you’re weaseling here.

    Indeed, I was wondering why you introduced it. Now you gave it a name.

    Actually, YOU introduced it. You can look it up. It was and remains a terrible analogy.

    Seriously, if you followed through consistently with your idea that (absence of) light is the cause of shadows, then it should not be a contentious matter to you that observers are causes of observations.

    Observers are necessary to observations, obviously. No observers, no observations. That is, as I said, a red herring. The speed of light has nothing whatever to do with vision.

  44. walto: No, I don’t agree with that assessment. I’d say the opposite–that pilot waves and Bohm’s “implicate order” make possible the reinstatement of non-spooky causation. The “distance” is, in a sense, eliminated.

    I guess it depends whether you are talking about distance-in-the-explicate-order (as I was) or distance-in-the-implicate-order, which I don’t know what-it-is, having misplaced by implicate-order-ruler.

  45. BruceS:
    Double Slit Intuitions
    My naive view was that interference was a mass effect:electrons travelled in waves which interfered.But, even if a single electron only is allowed in the double slit apparatus, an interference pattern still builds up if both slits are open and does not if one slit is closed.

    What do you mean “a single electron only is allowed”? The fact whether a single electron is detected, not merely assumed, makes all the difference. Because, in my view, it’s merely a common assumption that the adjective “single” is applicable to the electron. The atomic level is not made up of ball-like particles similar to solar systems, like they teach in school at first. It’s an energy field (space) where the substance takes particular shape only when the apparatus of detection imposes that shape on it.

    BruceS:
    Entanglement and Bell Inequalities
    It can be misleading to use ordinary conceptions of correlation.Bell referred to this by his Prof Bertlmann’s socks story.Suppose we know the prof always wears a red sock and a white sock; if we see one leg with a red sock, we know without looking the other must be red.But the correlation implied by violation of the Bell inequalities is subtler.To understand how, one needs to work through some simple math.

    I will give it a look some day. My own heroes of quantum mechanics are Planck, Bohr, and Pauli.

    BruceS:
    Special Relativity, Speed of Light, “Objective Instants”
    You are correct that scientifically working with concepts like the “speed of light ” requires operational definitions.Einstein used reference frames as the start:3D grids moving relative to each other, where each frame separately has synchronized clocks at each point in the grid.Both frames measure the same speed of light; but our intuition from everyday movement is that two observers moving relative to each other will measure a different speed for some third entity.Measurement of light’s speed can be carried out and Einstein’s postulate has been verified.

    The “intuition” (empirical assumption rather) that observers moving relative to each other will measure a different speed only applies if the speed really belongs to some third entity rather than to the observers. The fact that the speed of light is measured to be the same for all observers regardless of the observers’ speed means directly that whatever is being denoted by “speed of light” belongs to the observer. It has to do with the observation, it has to do with the way that thing is measured. This implication cannot get any more direct than this.

    More bluntly, if “speed of light” is a constant wherever we are and whatever we do, then it’s like the concept of “location”. Wherever we are and whatever we do, there’s “location”. This is our (subjective) property as much as it is an (objective) property of the universe. Subjective and objective are non-different here and it’s a scientific fact that the “speed of light” is similar to this.

    BruceS:
    Saying it is just perception of time that changes does not work for me.For if two clocks are synchronized, then travel in different frames, then are brought back together, their readings will differ.In fact, GPS as configured on satellites and receivers, would not work without this fact.I don’t see how it can be called only a perception.

    The problem is that you take perception to be subjective to humans. I meant it as an analog to measurement and I actually said so too.

    Instruments measure things by virtue of their mechanics (the mechanism inside). When the instrument moves or is located in different conditions, don’t you think the mechanism would be affected? To me the slowing down of a sped-up chronometer is as self-evident as its melting when it’s thrown into fire.

    And I compared it to Doppler effect, which is common in our ordinary range of experience. Or we can compare it to the fact that we see lightning first and hear thunder later. Different ranges of perception (vision and hearing) moving in their own respective channels (called “elements” in scholasticism) with different densities have different speed. Don’t you think that chronometers subjected to different gravitational conditions should be unaffected?

    BruceS:
    Thomist QM
    I had nor realized there was a Thomist view of the metaphysics of QM.For me, anyone who wants to work on metaphysics in QM needs the equivalent of a double PhD in physics and philosophy; people like Wallace, Maudlin, Albert.Further, I doubt that the detailed metaphysical implications of QM can be cogently done in natural language.The analysis needs to involve math, for QM is only expressible in detail inthe mathematical formalism.

    There will never be a single metaphysics and there will never be a single physics either. Empiricists necessarily perceive and construe the world differently from rationalists, and irrationalists do it still in their own various ways. Math will not solve it, because the debate is really over the interpretation of math.

  46. BruceS: I guess it depends whether you are talking about distance-in-the-explicate-order (as I was) or distance-in-the-implicate-order, which I don’t know what-it-is, having misplaced by implicate-order-ruler.

    The last person who borrowed mine never brought it back, so don’t look to me.

    But seriously, the whole point of the de Broglie/Bohm program seems to have been to eliminate (or explain) the spooky action that disturbed Einstein. What seemed “distant” are–in some “dimension”–right on top of each other. I don’t deny that Bohmianism is in heavy retreat, but the beauty of the idea seems to me undeniable, and I was kind of surprised at your surprise when I mentioned my preference of that vision to Hume’s (i.e., Bohr’s).

  47. Erik: What do you mean “a single electron only is allowed”? The fact whether a single electron is detected, not merely assumed, […] [The electron is] an energy field (space) where the substance takes particular shape only when the apparatus of detection imposes that shape on it.

    I mean the electron source is weak and only a single electron is detected. Saying that only a single electron was in the apparatus at a time is a standard way of describing the experiment in my experience.

    I have not previously heard electrons called energy fields. I’m more familiar with the wave nature referring to the Schrodinger equation, which describes a wave of probability (more accurately, not a probability but an amplitude which is a complex number).

    I will give it a look some day. My own heroes of quantum mechanics are Planck, Bohr, and Pauli.

    Great men, of course, but all worked before Bell’s results were discovered and put to the test. BTW, there is a fascinating book on Pauli and Jung, which I suspect you are already familiar with, but I link it just in case.

    To me the slowing down of a sped-up chronometer is as self-evident as its melting when it’s thrown into fire.

    Well, I guess your intuitions are different from mine, Newton’s, and (I suspect) most everyone who first hears about SR.

    And I compared it to Doppler effect, which is common in our ordinary range of experience. Or we can compare it to the fact that we see lightning first and hear thunder later. Different ranges of perception (vision and hearing) moving in their own respective channels (called “elements” in scholasticism) with different densities have different speed.

    I don’t really understand those analogies. To me, the Doppler effect is a change in frequency due to different relative velocity, and we hear thunder much later than the corresponding lightening flash because light travels much faster than sound. I had never related these two phenomena to time dilation.

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