What Determines That Which Is Possible And That Which is Impossible?

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    Branching off from here, it would be productive to discuss the question, from Epicurus' point of view,*** what determines the possible and the impossible? What distinguishes between the two?

    To get the discussion started I would suggest that the *only* thing that distinguishes the possible from the impossible is the properties and combinations of matter and void, and that there are no (1) divine / supernatural, or (2) purely logical, limits between the possible and the impossible.

    Agree? Disagree? More to the story? If so, what?

    And of course what I hear in the back of my mind in this question is Paul accusing the "pagans" of being "slaves to the weak and beggarly elements."

    That's a derogatory way of stating it, but in fact do not the elemental particles and their combinations, and the elemental particles alone (which includes all the circumstances in which they may combine) determine what is possible?

    ---

    *** Epicurus' point of view being the appropriate starting point here on the forum, rather than necessarily the end, of the discussion.

    Quote from Twentier

    Possible: that which is consistent with our senses.

    Impossible: that which contradicts our senses.

    But is that sufficient to deal with matters which we at any particular point we have not seen in the past, but which do not contradict the physics of what we have seen in the past, such as men flying? How do we know the limits of physics in situations that have not been tested?

    From Philodemus' "On methods of inference": "But (we answer) it will be sufficient for us to base our belief on probability in these matters, just as we do in regard to what is learned from trial; for example, that we shall be safe sailing in summer, since we have had experience of favourable winds in that season."


    My reading is that the emphasis is not on "what is possible", but "what is probable". So we need void to have motion "within our experience", i.e. given what we sense in our physical world. This means for all practical senses it is impossible to have motion without void, unless we sense evidence to the contrary.

    Possible: everything, depending on the degree of certainty

    Probable: that which is consistent with our senses and anticipation (prolepsis)

    Improbable: that which is incosistent with our senses and anticipation

    Impossible: nothing, depending on the degree of certainty


    To be fair, in the same section Philodemus justifies the small sun theory (I just had to make that disclosure).

    Quote from Don
    Quote from waterholic

    To be fair, in the same section Philodemus justifies the small sun theory (I just had to make that disclosure).

    On the size of the sun, check out Gellar-Goad's chapter in "Epicurus in Rome" (open access)

    https://www.cambridge.org/core/books/epicurus-in-rome/lucretius-on-the-size-of-the-sun/9B9D08457AB2AE45B44845464818346A#


    "The assertion that the sun is the size it appears became an Epicurean shibboleth, so to speak – a statement prompting reactions that distinguish Epicureans from non-Epicureans, the cognoscenti from the ignoramuses." - this passage scares me.

    We have two explanations: 1) there was a deeper meaning in the statement that the sun is as small as it appears, 2) there was a mistake made.

    It shouldn't be hard to accept that in an otherwise remarkable body of knowledge there are mistakes and misunderstandings. There is also a high probability of misintepretation given the chasm of time and language. The sun is big. Probably much bigger than Epicurus thought. He wasn't infallible. He didn't have to be.

    Quote from waterholic

    It shouldn't be hard to accept that in an otherwise remarkable body of knowledge there are mistakes and misunderstandings

    Nor is it appropriate to accept from unfriendly sources an interpretation that makes an opinion appear erroneous when an alternate interpretation from friendly sources which makes the interpretation accurate is available.

    I don't want that last comment of mine to sound snippy. I got interrupted in writing it and meant to add reference to the fact that this issue happens over and over and as much in the ethics and canonics as in the physics. Epicurus' enemies were only too happy to take his comments out of context and make them appear ridiculous, so we always need to be on the lookout for alternate explanations of things that appear incorrect, to see if the error is really in Epicurus or in the interpretation.

    Sometimes of course Epicurus is definitely wrong, but generally any errors are in precise application due to lack of information and technology, while the general reasoning behind the scenes is (and remains) valid.

    It did sound snippy Cassius, but not in any personal sense. I think you sensed that we are approaching the thorny issue of dogmatism. One thing that is much more important for me than the defence of the Epicurean position is testing my own ability to remain critical. We have issues like the laughable attacks of Cicero, who refuses to understand the meaning of pleasure or pretends not to understand.

    But then we have issues like coarseness and colours of atoms. We can say that we don't have a direct evidence that Epicurus himself thought that some atoms are coarse. Or we could say that he means something else that is more in-line with our present understanding of how atoms work. But these are just justifications where no justification is required. My point is: you cannot avoid people ridiculing without understanding. The only way to do that is the introduction of blasphemy as a concept. We know where that leads.

    Great conversation all around! I may be misunderstanding your point, waterholic -- but per Epicurus the atoms are colorless and perception of color is relative.

    Scholion on Epicurus, Letter to Hēródotos, D.L. 10.44: He says, moreover, that there is no quality at all for the atoms except for shape (τὸ σχῆμα), dimension (τὸ μέγεθος), and weight (τὸ βάρος) – that color varies with the position of the atoms, he states in his Twelve Elementary Principles.

    Plutarch, Against Kōlṓtēs, 1110B: Epicurus himself in the second book of his Reply to Theóphrastos, says that "colors are not intrinsic to bodies – but a result of certain arrangements and positions relative to the eye."

    Quote from Bryan

    Great conversation all around! I may be misunderstanding your point, waterholic -- but per Epicurus the atoms are colorless and perception of color is relative.

    Thank you Bryan, i stand corrected: i was in the process of reading something else and made a mistake.

    Quote from Cassius
    Quote from Twentier

    Possible: that which is consistent with our senses.

    Impossible: that which contradicts our senses.

    But is that sufficient to deal with matters which we at any particular point we have not seen in the past, but which do not contradict the physics of what we have seen in the past, such as men flying? How do we know the limits of physics in situations that have not been tested?

    As Epicurus wrote, THΣ AΛHΘEIAΣ EINAI TAΣ AIΣΘHΣEIΣ, "the truth is the sensations..." the foundation of knowledge. Whatever is left must be coherent with documented observations. Anything else leaves us without a point of reference to test false beliefs.

    I'll throw the full quote in here as well:

    D.L. 10.31: Therefore, in The Canon, Epicurus affirms that the criteria of truth are [1] the sensations and [2] the preconceptions and [3] the feelings, and the Epicureans (also affirm) [4] the image-based focus of the mind.

    Ἐν τοίνυν τῷ Κανόνι, λέγων ἐστὶν ὁ Ἐπίκουρος κριτήρια τῆς ἀληθείας εἶναι [1] τὰς αἰσθήσεις καὶ [2] προλήψεις καὶ [3] τὰ πάθη, οἱ δ᾽ Ἐπικούρειοι καὶ [4] τὰς φανταστικὰς ἐπιβολὰς τῆς διανοίας.

    Edited 6 times, last by Bryan (May 14, 2024 at 1:17 AM).

    So would modern science include 1, 2, and 4 from Bryan's list in post 15?

    If you want to give your mind some direct interaction with regard to the consideration of what is possible and what is impossible, try watching a "sci-fi/fantasy" movie.

    In fact, just last night I watched a sci-fi movie that had all sorts of impossible things happening.

    Now in our current world we have technology built upon science. But science is a complicated thing in itself. And science uses concepts, models, and theories.

    Here is an interesting read:

    List of existing technologies predicted in science fiction - Wikipedia

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