Necessary Being and Modal Logic

[@aaronchipp-miller9608]

Can't wait to hear what my pal Verity and my favorite artist frank zappa have been up to

[@dumbledorelives93]

This made me laugh way harder than it had any right to

[@megg.3933]

Underrated comment

[@osakagrindset]

Babe wake up, new kane b just dropped

[@KaneB]

That's novel. I suspect that far more people have been put to sleep by my videos than woken up by them.

[@PeterBarnes2]

@@KaneB There is philosophy content on KZbin far more dull than your videos. These videos are thoroughly enjoyable, if you have a taste for philosophy.

[@tudornaconecinii3609]

I have to say, the arguments presented didn't make me seriously consider either necessitism or contingentism, but they did a decent job of shaking one of my more foundational beliefs ("logic works wherever you are so it can't tell you where you are", as it were). Thanks for the food for thought.

[@funktorial]

really good work presenting a genuinely technically difficult topic, can't imagine this was easy to put together

[@KaneB]

Thank you!

[@andreasvox8068]

As a mathematician, I view all formulas that don't state the range of its quantifiers as suspicious. Or from a model theoretic perspective: there are models where modal logic is valid and there are models where modal logic is invalid, and necessitists and contingentists mix these models up.

[@rumfordc]

what makes a model "invalid" exactly? other than personal reasons for disliking it? if someone, anyone, manages to use it with some success then it has utility which is much more important than arbitrary validity.

[@JordanSmith-hh6rb]

Read hegel

[@СергейМакеев-ж2н]

This right here might be a "reductio ad absurdum" to show how broken the idea of "identity across worlds" is.

[@mothernature1755]

we should just get rid of possible worlds entirely and just treat them as useful fictions

[@СергейМакеев-ж2н]

@@mothernature1755 I approve, I'm already a fictionalist about modal facts in general. I am just expressing my opinion on further concepts _within the fiction._

[@СергейМакеев-ж2н]

@@rubeno.1195 Of course that's an important distinction. In philosophy, when someone uses the word "possible", an immediate follow-up question is: which modality? That means, which kind of possible? There is _physical_ modality ("with our laws of physics"), _logical_ modality ("possible" just means "non-contradictory"), and also _epistemic_ modality ("compatible with what I know about the world"), and some other ones. But there's also something called "metaphysical modality", which is supposed to be "the one true modality", which things are "genuinely possible" or "possible simpliciter". I don't believe *that* one exists.

[@rogerwitte]

I think the biggest weakness is the assumption that logic is philosophically neutral. To describe the world and to reason about it we use language. Logic gives us the consequences of our choice of language. But in choosing a language, we may already be making philosophical choices. In effect the choice of 'the strongest classical first order logic' entailing necessitism might be a good reason to consider other logics. Perhaps we should not always use the strongest available logic. Should we be seeking the weakest logic necessary to make our argument go through. I am inspired here by movements in mathematics like constructive mathematics, topos theory and reverse mathematics.

[@RobertElliotPahel-Short]

Laughing in Rust Option type.

[@gabri41200]

I am kinda of an extreme necessitist. I believe the universe is both deterministic, and it's natural laws couldn't be otherwise. I believe if you change, for instance, the speed of light in vacuum, some other underlying law of physics would enter in contradiction, so the speed of light can't be changed. Same for all other constants. So i believe the universe is necessary and the only possible world.

[@HerrEinzige]

Would Kane’s channel even exist if not for me liking and commenting on every video?

[@KaneB]

Thanks for the help!

[@IntegralDeLinha]

Wow! Great video on such a complex matter. Thank you!

[@ravenecho2410]

Videos are so interesting, the visuals and diagrams really help 😊

[@veganphilosopher1975]

Topic definitely calls for an analysis of the notion of existence. I imagine your analysis of that would be similar to your analysis of truth, that the term is somewhat vague and there are numerous edge cases which throw a wrench in the hope of a coherent theory

[@СергейМакеев-ж2н]

This is the first time I've seen an "actually" operator. Can you do a video about the arguments for and against using this operator?

[@KaneB]

It's not something I've looked into much, but yeah that might be interesting.

[@SamanthaPyper-sl4ye]

Since the observable (nonzero) universe went from "locally real" to "not locally real" a year ago, could you do a video on: Zero vs nonzero numbers Not-natural vs natural Locally real vs not locally real Seems like a good topic. Also the fact that Leibniz got it right all those years ago when he said: 0D is necessary and "more real" since it has no predecessor. 1D, 2D, 3D and 4D are contingent and "less real" since they all have an immediate predecessor. Kinda makes you think we're using the wrong calculus and geometry since we're using Newton's (now) contradictory version which says zero is not locally real and nonzero is locally real 🤔. Big thanks!

[@СергейМакеев-ж2н]

"Not locally real" has nothing to do with 3D and 4D. The entire debate between "locally real" and "not locally real" is formulated in infinite-D in the first place. Lower dimensions basically don't matter, except for the nuances of string theory.

[@wermaus]

I think of what actual necessary as just the things that have put the data into your mind as a system, which is a loosely connected system anyway which means different parts of it could maybe theoretically exist as different necessary forces for the reality of something being necessary. Also like we're in physics and it's hard to model our mind as a system without running into it's representative system of physics that it exists within. So for me it kind of seems to be the intersections of all these representative systems that define what life really is from the perspective of what we as a system are experiencing I guess?

[@MalkuthEmperor]

Well f me, i was a necessitist without knowing 😂 Love this!

[@isaacbarratt854]

I struggle to understand the disagreement between the necessitist and those who argue 'things' could have been otherwise: both agree that there exists the 'real' and 'hypothetical'. Being that a coin is a hypothetical but a piece of metal is a 'real' thing I dont understand what the dispute is: 'real' things can have hypothetical significance. This seems self evident. Is the concept of currency real? No: it is something we innovated, and the 'value' attached to 'real' things based on this hypothetical is relative (could be otherwise). Congratulations: 1. It is true that the hypothetical could be otherwise (this is what it means to have a hypothetical) 2. it is true that what 'is' is not hypothetical, and if it is real it 'ought' not be otherwise (necessity) 3. what is there to dispute: that things could have been otherwise or that something could become nothing? Do these people not protesteth too much? Why should I care about hypotheticals? I care only about what 'is'. Hypothetically I might consider how to make my life conditions better: but unless a hypothetical has an application it becomes useless to me even to consider. How is it useful to think that what 'is' 'ought' be otherwise? The contingentists who argue against necessity seem pugnacious to me (eg. not helpful at all: not useful at all: they offer me no solutions to my existential problem). The contingentist trivialises existence. What 'is' could be otherwise: they think about how things could be otherwise only because they loath what 'is'? Do these people hate life: only the person who distains or has contempt for life would prefer an 'ought' proposition over an 'is'.

[@martinbennett2228]

What puzzles me is the lack of distinction between a conditional mode that refers to the future and conditional modes that refer to the present (including the past). Whilst necessitism may apply to the former, the latter is necessarily contingent (on the past).

[@ManiH810]

What are your thoughts on Berkeley’s Idealism and immaterialism? It seems absurd to me.

[@Moley1Moleo]

If someone is a Necessetarian (perhaps for reasons of hard determinism and the like), does that allows them to afirm the Barton Formula, and otherwise also keep classical logic, without believing in these objects of mere possibility? i.e. everything is necesarrily something, and that something is precisely the thing that it is, no more and no less?

[@ravenecho2410]

For @30:00, i feel u might be able to say that X exists in no worlds, therefore there doesnt exist an X which can map to no Y, as X cannot exist But no world is like no connected or observable world or w/e

[@prophetrob]

If the only actually possible world is this world then all the "could have beens" you could ever come up with reduce to fantasies in your mind that are really couldn't have beens The ability to imagine things or events a different way than they are doesn't erase the possibility that they are the only way things could ever be

[@tudornaconecinii3609]

There are metaphysical systems which indeed commit to the claim that all counterfactuals are false, which seems to be what you are describing. Necessitism makes a more modest claim than that though.

[@jamesoneill7263]

That was an interesting remark at the end when you said that metaphysics should be informed by logic. Any recommendations in terms of books or articles that explains that view?

[@uwayn9829]

That would defy the concept of transcendance wouldnt it ?

[@Kyoz]

Imagine an infinite field of energy that generates consciousness as part of the whole but allows those consciousness to flake off and construct a world full of their ideas. Before you flake off, your thoughts are connected to the whole, so every idea/thought you have is either one that was already had before, and you just retrieved it from the whole, or you created a new thought, and added it to the whole. These are the "possible forms" or "merely possible concepts." As you fill the world with your ideas, some ideas get more attention than others. They get colored in and solidified or detailed into a necessary existence. If you were God, would you care what color ladybug shit is? Or would you leave it as a merely possible thing that can be whatever it ends up being. Let it be interpolated by the ladybugs environment and food. You save your attention for defining the more necessary aspects of your existence. Where will you be born and to whom? How is your childhood going to progress? And your death? Do you even need to die? Is it necessary? Or can you close your eyes and just wake back up inside the collective once you're done enjoying life? The only necessity for something to exist is that you wanted it in your world and started the world by plunging your consciousness into it. Designing a world means nothing if you never press the start button. (That's what I mean by plunging your consciousness into the world you create)

[@Masonova1]

I don't know how to tell the difference between a merely possible coin and a merely possible paperclip. It seems like all or most of the predicates before a coin's actuality are shared with those of a paperclip's. So how are possible objects identical to themselves? I worry that this is done by assuming the trivial solution -- every possible object is identical to every other one, modulo their predicates for actuality, and thus has no truly distinct form.

[@BLUYES422]

i wonder what can be derived mixing this idea with complexity theory. interesting framework of thought

[@danwylie-sears1134]

So they want us to replace "could exist" with "exists", "doesn't exist" with "is nothing", and "exists" with "is actual", with no effect other than to cause unnecessary confusion. (Not to be confused with continent confusion.) Yuck. And there's no substantive difference, once you get past the unnecessary confusion, so "yuck" and "that's not how people actually talk" are the only available criteria to distinguish between the two ways of speaking.

[@mothernature1755]

could you think of bare particulars as a kind of possiblium? So the bare particular that constitutes me could have not had the properties of a human and thus not been a human but something else, or nothing at all. So what it means to be actual on this view would be to have a bare particular with certain kinds of properties (like physical properties, mental properties, powers, etc.,)

[@howtoappearincompletely9739]

Impressive.

[@italogiardina8183]

Aristotle's sea battle began the debate from necessity. Although for contingency the battle may not have happened or may have happened even if it had happened that day. The battle does not have properties exclusive to itself where the battle's or coin's properties exist in virtue of a relation to observers such as humans then the coin exists contingently to an observer as does a battle. A coin absent of an observer is not a coin or legal tender, and so not a prototypical thing, as is a battle, at least from an anthropocentric view from somewhere. It is from quantum field theory that if the coin as a normative object exists then it does so as a diffused object which exists contingently in relation to a common sense social construction of what is classically termed to be 'in space' that has civilisational cognitive biases built into it based on evolutionary competition for resources of which a logic supervenes. Arguably the argument from necessity is masculinist and the dominant discourse linked to conquest and colonialism and the extraction of resources from so called underdeveloped societies. It's positivist and great for nations building exercises which gives the population a boost and cash injection into the hip pocket too. An approach to the wave function as an actual picture of reality seems to require a non classic logic. Logic as a civilisation embedded oxymoron reveals itself which is nicely done here. Thanks for the philosophy news update!

[@SamanthaPyper-sl4ye]

Something = spatial extension Nothing = no spatial extension Quarks have no spatial extension and it's impossible for protons and neutrons, which have spatial extension, to exist without subatomically containing them within themselves.

[@philbelanger2]

I think that the theorem of first-order logic on which the proof of the Barcan formula relies is very counter-intuitive. The formula (¬Ey x=y → Ex ¬Ey x=y) basically says that if something doesn't exist, then there exists something which doesn't exist, which sounds like a contradiction. It's noteworthy imo that if we assume that every term in classical logic refers to an existing object, then the formula is vacuously true for every term; that is, only true because the antecedent is false. I don't know what to do about this but I find it very unsatisfying. Maybe existential generalization, as a rule, should be restricted to cases where it is true that the object has the property in question.

[@tudornaconecinii3609]

I think you might be seeing a contradiction where there isn't one because the formula written in the conventional way instead of the formal way makes it unclear which parts of it are propositions. More specifically, the parentheses are implied instead of written down. Here: ¬Ey.(x=y) → Ex.(¬Ey.(x=y)). ¬Ey itself is not a proposition. The proposition in the antecedent is "there doesn't exist a y *such that* it's also an x".

[@philbelanger2]

@@tudornaconecinii3609 To be clear, I meant that the consequent sounds like a contradiction. You can read the formula ¬Ey x=y as saying "x doesn't exist", since it says that there is nothing that is identical to x. (And you definitely shouldn't interpret it as "there doesn't exist a y such that it's also an x"; x here refers to an object, it's not a predicate.)

[@tudornaconecinii3609]

@@philbelanger2 No, that's... not how first order logic works.

[@KaneB]

​@@philbelanger2 The consequent is inconsistent in classical logic, yeah. So we would deny the antecedent for the reason you mention. I'm not really sure why this is a problem though; there isn't anything wrong with using vacuous truths in proofs.

[@GottfriedLeibnizYT]

"Necessitism is the view that necessarily everything is necessarily something". Sounds like essentialism, I guess.

[@fullwondrhh]

Could you elaborate on this?

[@GottfriedLeibnizYT]

@@fullwondrhh Essentialism is a traditional view in metaphysics claiming that objects have a set of attributes that are necessary to their identity.

[@KaneB]

I think necessitism is in conflict with some common essentialist views, in particular claims about the essential properties of individuals. If I have any essential properties at all, we'd expect them to be things such as being human or having a mind. But according to the necessitist, there are worlds in which I am not human and worlds in which I have no mind (just take those worlds in which life never evolved). So these are only contingent properties of me. Another common claim is that certain facts about my origins are essential to me, such as that I was born from my specific parents. Anybody born from any other parents could not have been me. But there are worlds in which I was never born from those parents (worlds in which my parents exist, but they never had a child).

[@СергейМакеев-ж2н]

Why is it so counter-intuitive to reject the necessitation rule? I can intuitively see that it's valid for a *closed* formula, but for an open one? Just seems straightforwardly false!

[@KaneB]

I don't think it's counterintuitive at all, but the issue here isn't really about intuitions. Necessitation is a principle of all normal modal logics. If we reject necessitation, this forces a revision in our modal logic that Williamson thinks will incur a significant cost in the simplicity and strength of the system. I guess the challenge is: "put up or shut up -- if you deny necessitation, which logic do you think is the right one?"

[@СергейМакеев-ж2н]

@@KaneB Which logic? Simply put, the logic that is just like classical *except* that necessitation only applies to closed formulas. Everything else stays the same. Actually, I looked into it in the meantime, and it turns out Kripke thought the same thing. So it's not even my original idea. Specifically, Kripke was altogether skeptical of the theorem-ness of open formulas.

[@KaneB]

@m4ev6jb7d Actually, Williamson does discuss this briefly. He says it doesn't work because the problem just arises again if we allow proper names in place of free variables. Consider: (1) ∃y k=y (2) □∃y k=y Suppose that "k" names K2. Contingentists have to reject (2), since it says that K2 is necessarily something. So this means they must either reject (1), i.e. adopt a free logic, or restrict necessitation again. I take it that for some reason, there would be something unattractive about restricting necessitation here, though Williamson doesn't elaborate on this point. Apparently that's not the route that Kripke took, though: "Kripke avoids the issue only by excluding proper names and other closed singular terms from his formal language. Since such closed singular terms are perfectly legitimate, even on Kripke’s own views in the philosophy of language, their exclusion is wholly artificial."

[@СергейМакеев-ж2н]

@@KaneB I don't put much stock into proper names anyway. They are an artifact of natural language, like polysemous words, or like the act of "verbing" a noun. I don't think they "deserve" to be put into a formal system.

[@onion4062]

isn't a coin a possible coin merely in virtue of it existing in some possible world?

[@KaneB]

It's probably easier to communicate this point by thinking about a kind that we all agree isn't instantiated, so consider talking donkeys. If there is a possible world in which there is a talking donkey, then this would make propositions such as "it is possible that there are talking donkeys" or "there could have been talking donkeys" true. But it wouldn't follow from this alone that, in the actual world, there exists a possible talking donkey. This is what the necessitist is claiming. If "Frank" names a talking donkey in any possible world, then Frank exists in every world, including the actual world -- though Frank may not be a talking donkey in every world. In the actual world, since there are no talking donkeys, Frank won't be a talking donkey but a merely possible talking donkey. What makes Frank a merely possible talking donkey in the actual world is not that there is some other possible world in which Frank exists (after all, the fact that Frank exists in some other possible world doesn't in itself mean that he exists in the actual world!). What makes Frank a merely possible talking donkey in the actual world is that Frank exists in the actual world and Frank could have been a talking donkey (i.e. in other possible worlds, Frank is a talking donkey).

[@OBGynKenobi]

Sounds like a rewording of the many worlds theory of physics. Ie, there is a world where this video doesn't exist and could not have existed.

[@KaneB]

Bear in mind that the term "world" is used differently in physics vs modal metaphysics. The other "worlds" of the many-worlds interpretation are not strictly speaking others possible worlds; they are just different parts of the actual world. Possible worlds are not causally connected; indeed, on most views of modal metaphysics, possible worlds are not even concrete but are abstract entities of some sort (say, sets of propositions). If the many-worlds interpretation is true, then this tells us that the actual world is much larger than what we initially thought. It doesn't tell us anything about what happens in other possible worlds. Another way to see this is to note that there are possible worlds with different laws of physics. There are possible worlds in which the many-worlds interpretation is true, so that there are branching universes; there are possible worlds in which the Bohmian interpretation is true; possible worlds in which Newtonian mechanics is true; possible worlds in which Aristotelian cosmology is true... etc etc. The only limit on possible worlds is logical consistency. (What I've described here is the standard view of the relation between the many-worlds interpretation and modal metaphysics. There are actually a few people who defend the view that the many worlds of the many-worlds interpretation are literally possible worlds. See Alastair Wilson's book "The Nature of Contingency".)

[@OBGynKenobi]

@@KaneB yes but if we assume that there are infinitely many worlds then , then, for example, if there can be a coin, then there will be a coin. It's no longer a matter of "necessariliness." It WILL exist. That is, in an infinite universe, anything you can think of (within the boundaries of the laws of physics,) will exist.

[@micahbelew8129]

Kane, wondering if you received my email.

[@MarshmallowRadiation]

From a materialist perspective, the "possible coin" would indeed exist concretely: as all of the metal that would have made up the coin. In that way, the necessitist does not need to posit any non-physical possible objects, but just point to the exact matter and energy in time and space that could have been differently shaped, no immaterial objects required. Personally, I find that to be the most intuitive understanding.

[@f1urps]

I will happily listen to Kane talk for 40 minutes about anything, and I enjoyed this video, but my god, this has to be the most pointless philosophical distinction ever. So much of metaphysics is just word games.

[@KaneB]

I appreciate it! I enjoy this kind of metaphysics, against my better judgment.

[@ReasonWithRainer]

Necessitism says that nothing is nothing basically lol

[@InventiveHarvest]

This is a case where both theories are degenerate research programmes. Each side of the debate has counter-examples that falsify the other theory. Both sides of the debate are attempting to exclude the other theory by restricting definition. The way to progress modal logic would be to determine under which contexts one should use free logic or standard logic. In cases where "existence" refers to "non-existent" objects also known as "concepts" then classical logic would be a fine approach. In cases where "existence" refers to what is actualized, then free logic would be the appropriate approach.

[@СергейМакеев-ж2н]

Isn't it the exact opposite? Free logics for when terms can refer to "concepts", classical logic for actualized ones?

[@InventiveHarvest]

​@@СергейМакеев-ж2н perhaps. The video was pretty complicated and I may have mis-understood. But my takeaway from it was that the existence of possible objects was a consequence of classical modal logic. In other words, the Barcan formula is derived from the rules of classical modal logic. Free logic allows for empty terms and non-existent objects.

[@СергейМакеев-ж2н]

@@InventiveHarvest As I wrote in another comment, the classical necessitation rule seems very suspicious to me. I think it should only be applied to statements without free variables, and then all the problems with possible objects will disappear. But that's just me. I haven't studied the intersection of first-order logic and modal logic. This whole business of putting terms from one world into a formula describing other worlds seems suspicious.

[@InventiveHarvest]

@@СергейМакеев-ж2н the classic modal logic would be useful for statements like "unicorns necessarily have one horn"

[@СергейМакеев-ж2н]

@@InventiveHarvest □( ∀x ( IsAUnicorn(x) -> HasOneHorn(x) ) ) Seems classically correct to me. Is it different in free logic?

[@PROtoss987]

a good example of why metaphysics is garbage. this is a category error, coins or sons are vaguely defined groupings of particles, not mathematical concepts to reason the potential existence of by manipulating symbols. likewise for "actual world", whatever that is meant to mean. set of particles? who knows? And I see no reason to believe there can't be something that could have actually not existed. the denial of this is just circular reasoning.

[@joecotter6803]

Which goes to show that Modal Logic is a lot of bunk.(WVO Quine). Round and round we go with word lasagne, layer and layer of verbiage topped off with a good dollop of word salad cream. Give up on this. Wilkinson might not have existed and his book wouldn't have been published and we would all have been better off. You will go mad if you go on like this and end up like Chalmers in a simulation spiralling up your own arse in an infinite regress. 'All possible coins are coins'. Read it. Examine. 'All possible coins are not coins'. Take your pick. Whatever answer you pick results in precisely nothing. Pack it in. Do some philosophy. This is friendly advice. You are very talented but wasting your time in this ludicrous venture. I am a possible Patreon subscriber, send a link please. Not a link to a payment page but a link to your content.