• Banno
    24.8k
    Odd that these replies are not about my actual rebuttal of the OP.
  • fishfry
    3.4k
    Odd that these replies are not about my actual rebuttal of the OP.Banno

    I admit to not reading the entire thread in detail. OP noted that there's a disconnect between classical sentential logic and the mysterious "here but not here" logic of quantum physics. I'm pointing out that Aristotle's logic is not sufficient to explain the world, especially in view of modern developments in logic. I'd think such an assertion would be noncontroversial. Perhaps you're right that I have no idea what you're trying to say. What are you trying to say? OP said that P ^ not-P is a contradiction in classical logic, yet seems to describe certain aspects of modern physics. I pointed out that modern physics doesn't seem to be well described by classical logic. I'm happy to stand by that statement.
  • Banno
    24.8k
    But logic, as an aspect of the human mind, is an abstraction. Like numbers. Like justice, or law, or religion. These are abstractions of the mind that become part of the real world only through common agreement. Social truths, as in Searle's idea of the Construction of Social Reality.fishfry

    I enjoyed Searle's book.

    The argument here, however, as no doubt FishFry will agree, is missing an assumption needed to make it valid: that all abstractions become part of the real world only through common agreement.

    That might be an interesting side topic.
  • Banno
    24.8k
    I pointed out that modern physics doesn't seem to be well described by classical logic.fishfry

    That's of course not the same as saying that modern physics is illogical, which seems to be the implication of the OP.

    The series of posts I made on the first page show that the apparent contradiction in the OP dissipates on examination. @creativesoul put the guts of the argument together for us - thanks!

    I think it clear enough.
  • fishfry
    3.4k
    That's of course not the same as saying that modern physics is illogical, which seems to be the implication of the OP.Banno

    So take it up with the OP. It's certainly not something I said.
  • Hachem
    384
    That's of course not the same as saying that modern physics is illogicalBanno

    Agreed. There is nothing wrong with the logic of modern physics as far as I can see. Once you accept their assumptions of, for instance, non-locality, you can argue quite logically for a conclusion that supports it.

    It would be too simple to limit the discussion of modern physics to a simple formalism. Just like classic physics, it makes use of all aspects of human thinking.
  • Banno
    24.8k
    Non-locality is an observation, and a conclusion, not an assumption. I really don't want your support. It does not help.
  • Hachem
    384

    I really do not care what you think. I am not supporting you. I have very little respect for you.

    And no, non-locality is not an observation. The fact that you can say that without hesitation proves to me once more how little you understand about science. Even if you think you know a lot.

    Out of respect for the thread, I will not try and fight our differences here. In fact I do not see, as little as you do, why we should continue the fight anyway.
  • litewave
    827
    There can be no contradiction in reality, that is, in propositions that correctly characterize reality. A genuine contradiction would amount to saying that something is not identical to itself, that it is not what it is - and that is nonsense.
  • Hachem
    384

    If you believe that, as I do, then you cannot believe in non-locality.
  • litewave
    827
    If you believe that, as I do, then you cannot believe in non-locality.Hachem

    What is inconsistent about non-locality?
  • fishfry
    3.4k
    There can be no contradiction in realitylitewave

    https://en.wikipedia.org/wiki/Paraconsistent_logic

    https://en.wikipedia.org/wiki/Law_of_excluded_middle#Criticisms

    People seem to think "logic" means Aristotle's logic from 2400 years ago. Nothing could be further from the truth. Today logicians are perfectly comfortable embracing and formalizing contradictions.
  • litewave
    827
    But do you mean to say that in reality there can be a thing that is not identical to itself?
  • Hachem
    384
    What is inconsistent about non-locality?litewave

    what is consistent about non-locality?
  • Hachem
    384

    I wrote that almost one year and a half ago. I haven't thought about this issue since, but I think I can still stand behind what I said.
    https://philpapers.org/post/15494
  • litewave
    827
    what is consistent about non-locality?Hachem

    Well, non-locality means there are some instantaneous correlations across space. On the surface this may seem inconsistent with the speed limit according to theory of relativity but in fact there is no motion of a signal between the correlated events, so the speed limit is not violated.
  • fishfry
    3.4k
    But do you mean to say that in reality there can be a thing that is not identical to itself?litewave

    I'm at a loss to understand why you would ask me that question based on anything I wrote in this thread. Care to explain?

    The validity of the law of identity is a subject worthy of its own thread. But I said nothing about it here.
  • litewave
    827
    I'm at a loss to understand why you would ask me that question based on anything I wrote in this thread. Care to explain?

    The validity of the law of identity is a subject worthy of its own thread. But I said nothing about it here.
    fishfry

    I thought you disagreed with my statement that there can be no contradiction in reality. Violation of the law of identity would be a contradiction.
  • fishfry
    3.4k
    I thought you disagreed with my statementlitewave

    Banno's been responding to me but I don't remember what you are referring to. Can you help me understand why you think I'm denying the law of identity as it pertains to reality, based on anything I wrote here? Apparently my pointing out that classical sentential calculus is a poor tool for modeling modern physics has triggered a lot of people. I thought it was rather self-evident.
  • litewave
    827
    Apparently my pointing out that classical sentential calculus is a poor tool for modeling modern physics has triggered a lot of people. I thought it was rather self-evident.fishfry

    I claim that reality can contain no contradiction in the classical logic sense, so I don't accept a logic that allows reality to contain a classical contradiction.
  • Hachem
    384
    I claim that reality can contain no contradiction in the classical logic sense, so I don't accept a logic that allows reality to contain a classical contradiction.litewave

    You took the words right out of my mouth. I don't need to sleep on it.
  • fishfry
    3.4k
    I claim that reality can contain no contradiction in the classical logic senselitewave

    Well there's no way to know. We do know that contemporary theories of physics can not be incorporated into a single noncontradictory framework. Past that, we really have no way to say anything.

    Out of curiosity, what's your evidence for your claim? Or even a plausibility argument?

    How does your claim differ from a theological argument that God created it all in six days and watched pro football games on the seventh? You have a claim but you haven't supplied evidence.
  • Hachem
    384

    The question is not addressed to me, still, I will give my own opinion on this matter.

    I think your question in itself would be considered biased by the proponents of Quantum Theory because you make it sound as though it is based on a metaphysical decision.

    I think QT is a metaphysical theory, but one embedded in science and which makes use of scientific methods.

    I would also be the last one to put a stamp of non-scientificity on all its findings because of these metaphysical bases.

    QT is a scientific theory and must be treated as such.

    To reject its metaphysical assumptions, as Einstein did, is I think not sufficient. His efforts can also be considered historically as failed attempts.

    The discussion must not get stuck in metaphysical assertions to and fro but must ultimately be fought on the empirical field.

    It looks like QT has the home advantage and that many of its predictions have been confirmed empirically.

    I do not think that it the case. I am convinced, and I will present no proof for this conviction, that most confirmations in fact assume that which has to be proven.

    The link I have given is just one example of how the epistemological analysis of QT arguments could look like.

    I have also to admit to the limit of my endeavors. Like I said, the fight will have to be fought on the empirical field, and not at the metaphysical or philosophical level.

    That means that ultimately the fight will have to be fought by physicists, and not by philosophers. The latter can only show that it is possible to build a metaphysical alternative to QT.
  • Banno
    24.8k
    @fishfry What are the inconsistencies in physics? Specifically. Realy interested.
  • fishfry
    3.4k
    What are the inconsistencies in physics? Specifically. Realy interested.Banno

    Can't find a single theory that unifies quantum physics and gravity. Isn't this the most famous problem in physics? From Einstein to Witten and beyond, nobody's cracked it yet.

    I didn't say there are "inconsistencies in physics." I wish you'd quote what I actually said, which was:

    We do know that contemporary theories of physics can not be incorporated into a single noncontradictory framework.fishfry

    This is an objectively true statement. It could be falsified tomorrow morning, but as of this writing, it's factually correct.

    Didn't I specifically quote this paragraph in this thread earlier?

    At the present time, there are two foundational theories in physics: the Standard Model of particle physics and general relativity. Many parts of these theories have been put on an axiomatic basis. However, physics as a whole has not, and in fact the Standard Model is not even logically consistent with general relativity, indicating the need for a still unknown theory of quantum gravity. The solution of Hilbert's sixth problem thus remains open.

    https://en.wikipedia.org/wiki/Hilbert%27s_sixth_problem#Status
  • Banno
    24.8k
    fact the Standard Model is not even logically consistent with general relativity,fishfry

    When I were lad, if two theories were not logically consistent, then one contradicted the other.

    But if that is not what you intended to say, then forgive me my misunderstanding.
  • litewave
    827
    Out of curiosity, what's your evidence for your claim? Or even a plausibility argument?fishfry

    As I said, if reality contained a contradiction it would mean that something is not identical to itself - and that would be nonsense.

    Moreover, if you abandon the law of non-contradiction all your arguments automatically refute themselves.
  • Banno
    24.8k
    If we were to come across propositions that were apparently both true and contradictory, the proper response would of course be to re-phrase the propositions in order to remove the contradiction.
  • litewave
    827
    Yes, because their truth or contradiction is only apparent.
  • Streetlight
    9.1k
    It's worth noting the distinction between saying that 'there are no contradictions in nature' (implying that, at least in principle, there could be) and that 'the very idea of a contradiction is inapplicable to nature' (i.e. that it is not impossible but non-sensical to speak of 'things/entities/events/actions' as contradictory or not: an error of grammar, as if to ask if an idea is coloured or not). The OP trades on the second kind of error - it is a grammatical mistake.
bold
italic
underline
strike
code
quote
ulist
image
url
mention
reveal
youtube
tweet
Add a Comment

Welcome to The Philosophy Forum!

Get involved in philosophical discussions about knowledge, truth, language, consciousness, science, politics, religion, logic and mathematics, art, history, and lots more. No ads, no clutter, and very little agreement — just fascinating conversations.