# Modal Logic Question
**URL:** https://www.ilovephilosophy.com/t/modal-logic-question/49320
**Category:** Science, Technology, and Math
**Created:** [September 5, 2023, 11:15am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320 "2023-09-05T11:15:46Z")
**Posts on this page:** 19
**Page:** 4
### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [August 25, 2024, 8:07am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/61 "2024-08-25T08:07:35Z")
> [@Mr\_Reasonable](#):
>
> identity theory, or reductive and functional descriptions
identity
reductive
functional
1. Is that a harmonic triad? Identity yellow, reductive blue, functional red?
2. What does reductive mean?
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [August 30, 2024, 10:33am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/62 "2024-08-30T10:33:36Z")
For posterity.
> [@Absolute Randomness](https://www.ilovephilosophy.com/t/absolute-randomness/8054/3608):
>
> Wilfred Hodges thinks “identical” means you’re dealing with two different things, but clearly A=A means every particular thing (and everything taken together, I would assume??) is identical to itself. @PZR … the particular identities & general predicates are looking at each other funny. Just letting you know.
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [August 30, 2024, 10:34am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/63 "2024-08-30T10:34:16Z")
Reductive… a limiting factor, no?
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### Author:  [@Hudjefa](https://www.ilovephilosophy.com/u/Hudjefa)
#### Post date: [September 6, 2024, 6:41am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/64 "2024-09-06T06:41:30Z")
For the moment, possibly necessary “seems to” imply possibly not necessary. I don’t see how necessary A follows from possibly necessary A.
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [September 6, 2024, 9:06am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/65 "2024-09-06T09:06:41Z")
Does reductive just mean definite/defined?
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [September 6, 2024, 9:07am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/66 "2024-09-06T09:07:52Z")
If you can’t rule out the necessary as IMPOSSIBLE, then it’s necessary… is my feeling.
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [September 6, 2024, 9:12am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/67 "2024-09-06T09:12:00Z")
the case=definitive proof of concept
methinks
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [September 6, 2024, 9:51am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/68 "2024-09-06T09:51:11Z")
> [@Ichthus77](#):
>
> 10:40 B corollary it’s poss nec A implies A is in fact the case (one way to read: whatever is possibly necessary is in fact the case)
>
> Question: If whatever is necessary is in fact the case (Axiom M), why are only one of those corollaries controversial? Modal ontological argument? Why only one results in it?
Prolly same reason folks prefer Boole to Aristotle on existential import, I’m guessing.
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [September 8, 2024, 10:50am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/69 "2024-09-08T10:50:39Z")
Piecing things together:
Jorgensen’s dilemma resolution. (only indicatives have truth value — as in — a nonempty category, or a particular instance/individual)
If you can easily solve “individuals” by saying them as “categoricals” (“All people who are Socrates…”) — then rephrasing imperatives as indicatives should be easy enough, just like rephrasing from passive to active voice. It won’t prove existence, like it wouldn’t prove the existence of Socrates. Are you going to DENY person equals person? That’s denying the law of identity.
Don’t have it all yet.
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [September 8, 2024, 10:53am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/70 "2024-09-08T10:53:31Z")
If you’re treating every person as category and you’re treating every category as necessary then you’re treating every person as necessary. That’s gonna glitch (isn’t it?).
This is partly why I need help translating between logics for the square of opposition.
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [September 18, 2024, 11:48am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/71 "2024-09-18T11:48:38Z")
> [@The Harmonic Triads](https://www.ilovephilosophy.com/t/the-harmonic-triads/48486/327):
>
> red: ~1, 1 empty/full (never/impossible) or (always/necessary)
>
> blue: 0 (default good/baseline) (self=other)
>
> yellow: % anywhere in the middle (contingent) “increasing toward fullness or decreasing/nihilating away from fullness”
Necessary doesn’t mean _will_ happen. Only sufficient does.
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [November 2, 2024, 10:05am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/72 "2024-11-02T10:05:15Z")
> [@Ichthus77](#):
>
> rephrasing imperatives as indicatives
Related:
> [@Resolving existential import/fallacy](https://www.ilovephilosophy.com/t/resolving-existential-import-fallacy/80586):
>
> Subalternation (done wrong) commits the existential fallacy when the terms are empty (the premises aren’t true), because existential import (at at least one time, t, which has essential/thetic import now if that time, t, is not now) is required (empty terms are forbidden, true universals/superalterns are required) in order for subalternation (not to mention affirmation) to “go through”. \*\*now means: present to the evaluator Resolves this conundrum: existential import: [Exis…](https://www.britannica.com/topic/existential-import#:~:text=existential%20import%2C%20in%20syllogistic%2C%20the%20logical%20implication%20by,P%E2%80%9D%20or%20%E2%80%9CSome%20S%20is%20not%20P%2C%E2%80%9D%20respectively%29)
Also:
“A counter-obligatory imperative is no imperative at all” (my phrasing of Augustine’s Law)
Also included the other side of Kant’s Law: Just because you can doesn’t mean you should.
I like the distinctions between doing something, commanding something, something being obligatory, something being possible, and something being permitted (not prohibited) (against such things there is no obligation… or obligatory imperative).
I think I should not have underlined the second A in Augustine’s Law. Doh!
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [November 2, 2024, 12:30pm UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/73 "2024-11-02T12:30:48Z")
Is there language in modal logic for necessary versus sufficient?
Does it come up with the phrase ceteris paribus?
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [December 2, 2025, 10:02am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/74 "2025-12-02T10:02:56Z")
> [@Resolving existential import/fallacy](https://www.ilovephilosophy.com/t/resolving-existential-import-fallacy/80586/40):
>
> Ascending & descending, bitches!!!
puh-huhhhh!!!
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### Author:  [@Mr\_Reasonable](https://www.ilovephilosophy.com/u/Mr_Reasonable)
#### Post date: [December 7, 2025, 2:09am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/75 "2025-12-07T02:09:51Z")
you’re still on this stuff?
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [December 7, 2025, 2:31am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/76 "2025-12-07T02:31:17Z")
Oh man, I’m gonna be on this stuff for quite some time. Maybe my whole life … however long that might be. Could be an open-ended infinity.
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### Author:  [@Mr\_Reasonable](https://www.ilovephilosophy.com/u/Mr_Reasonable)
#### Post date: [January 10, 2026, 7:03am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/77 "2026-01-10T07:03:15Z")
What’s the goal?
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [January 10, 2026, 7:35am UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/78 "2026-01-10T07:35:07Z")
Wholesome joy tastes beautiful.
Still on this:
> [@Without \_\_\_\_\_\_ life would be a \_\_\_\_\_\_\_\_\_.](https://www.ilovephilosophy.com/t/without-life-would-be-a/49196/73):
>
> I think you mean neuroscientist instead of philosopher, and instead of fallacy you mean heuristic. I will attempt to fix this confusion.
And this:
[Project: Deconstructing Consent Violation](https://www.ilovephilosophy.com/t/project-deconstructing-consent-violation/49328)?
Always this:
> [@The Harmonic Triads](https://www.ilovephilosophy.com/t/the-harmonic-triads/48486):
>
> Something I’m playing with to organize some dialectics that make three-part syntheses. The attached Venn diagram is just a sample/key to start. See this Google Sheet for many more triads. [https://docs.google.com/spreadsheets/d/1wxtknEW5QLl8etwcmtjFOwUEQNbqGwsKpNeaQmPiY3M/edit?fbclid=IwAR3v5nqXBU4fabaJ4h\_GvNpnyI0RcqExhSObc-DIoUlOCWhMIg9ezBMnTmA#gid=0](https://docs.google.com/spreadsheets/d/1wxtknEW5QLl8etwcmtjFOwUEQNbqGwsKpNeaQmPiY3M/edit?fbclid=IwAR3v5nqXBU4fabaJ4h_GvNpnyI0RcqExhSObc-DIoUlOCWhMIg9ezBMnTmA#gid=0)
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### Author:  [@Ichthus77](https://www.ilovephilosophy.com/u/Ichthus77)
#### Post date: [May 24, 2026, 4:12pm UTC](https://www.ilovephilosophy.com/t/modal-logic-question/49320/79 "2026-05-24T16:12:49Z")
Gee. I would not have even asked the question in the original post if I had taken better notes in the first place. I may have more to say, but here are my notes for now.
This is also relevant:
> [@Ichthus77](#):
>
> If you can’t rule out the necessary as IMPOSSIBLE, then it’s necessary… is my feeling.
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