Yes, indeed. I'll stand by what I said in my first post:This got complicated. — Tom Storm
How do we know there isn’t anything beyond our reality?
Because reality is what there is.
To posit something "beyond reality" is to posit more of what there is. It is to extend reality.
This is why the extent of our language is the extent of our world.
Hopefully, replacing "limit" with "extent" will head off some of the misplaced criticism of that phrase.
The other mistake here is to equate what we experience with what is real, and so to conflate "How do we know there isn’t anything beyond our experience" with "How do we know there isn’t anything beyond our reality".
"Beyond reality" is not a region; it is a grammatical error. — Banno
Has he? He claimed that one interpretation was more rational. His reasoning was questionable, and questioned.Philosophim has given you his reasoning for preferring his meaning — AmadeusD
But it is possible that he is not doing that. I may have misunderstood, but I think the idea is that the actual world is regarded as a possible world, which does not imply that there are two worlds here. — Ludwig V
If you continue to insist that you can use the same term to refer to different things, within the same argument (to equivocate), and to insist that there is no logical inconsistency in doing this, and also assert that the person who points out this equivocation to you, is the one making the error, then I think there is not much point in proceeding. — Metaphysician Undercover
Good. Following your analogy, one of the books in your encyclopaedia is about the actual world. You might take it out and read it. In another possible world, another possible you can take out a different book about their world, treating it as their actual world, and read, it perhaps with as much satisfaction as you derive from reading yours.It all seems perfectly clear. — Ludwig V
Can we also write ◇p→(p v ~p)? — Ludwig V
Yep. The U and the ∃ quantify within a world, the ☐ and the ◇ across worlds.A quantifer tells us about the number of items in a domain that have a certain property, like all, or some. So "necessary" will mean that all the items (in every possible world) have the property. Possibly mean at least some of them do. — frank
Your Example | Tarski Semantics Symbol
--------------------------------------------|-----------------------------
Domain: D = { John, Algol, BASIC } | Domain: D
Individual constants: John, Algol, BASIC | Individual constants: a, b, c ∈ D
Predicate symbols:
P(x) = "Is John's pet" | Predicate symbol: P(x), 1-ary
D(x) = "Is a dog" | Predicate symbol: D(x), 1-ary
L(x,y) = "Is loved by" | Predicate symbol: L(x,y), 2-ary
Extensions:
Ext(P) = { Algol, BASIC } | Extension of P: Ext(P) ⊆ D
Ext(D) = { Algol, BASIC } | Extension of D: Ext(D) ⊆ D
Ext(L) = { (John, Algol), (John, BASIC) } | Extension of L: Ext(L) ⊆ D × D
Satisfaction:
a satisfies P iff a ∈ Ext(P) | a ∈ D satisfies P iff a ∈ Ext(P)
(a,b) satisfies L iff (a,b) ∈ Ext(L)| (a,b) ∈ D × D satisfies L iff (a,b) ∈ Ext(L)
Truth of formulas:
P(Algol) is true iff Algol ∈ Ext(P) | Atomic formula true if tuple ∈ extension
L(John, Algol) is true iff (John, Algol) ∈ Ext(L)| Atomic formula true if tuple ∈ extension
TRUE satisfies "John has two dogs" | 0-ary sentence letter is TRUE iff its extension = TRUE
That's a start. Good.Keep in mind that the equation he rejects, p→◇p, is valid in both S4 and S5.
— Banno
I don't necessarily reject this. — Metaphysician Undercover
The extension of a denoting expression, or term, such as a name or a definite description is its referent, the thing that it refers to; the extension of a predicate is the set of things it applies to; and the extension of a sentence is its truth value. — 1.1 Extensionality Lost
n = 0 (i.e., π is a sentence letter) and the extension of π is the truth value TRUE; or
n = 1 and aτ1 is in the extension of π; or
n > 1 and ⟨aτ1, ..., aτn⟩ is in the extension of π. — 1.2 Extensionality Regained
Not really.I think you saying that this particular world is the only one that corresponds to the facts of reality as we experience them, which is not a strong statement since I don't see how it could be otherwise. — noAxioms
Look Over There!! — Philosophim
You privilege one meaning over others.
If you are not doing that, then you cannot maintain that "trans women are women" is false. — Banno
You privilege one meaning over others.
If you are not doing that, then you cannot maintain that "trans women are women" is false. — Banno
Definition A.1 (Extensionality). If A and B are sets, then A=B iff every element of A is also an element of B , and vice versa.
...as, for example, you give the advantage to 'sex of the person' over 'gender of a person' when you say...advantage... — Philosophim
I'm claiming the context of 'woman/man' unmodified is most rationally interpreted to mean 'sex of the person' — Philosophim
Where have I ever advocated privilege? — Philosophim
I'm claiming the context of 'woman/man' unmodified is most rationally interpreted to mean 'sex of the person' — Philosophim
You can't maintain that while simultaneously maintaining that the One True Meaning is the biological one.Ok, I JUST told you I said the term was polysemous, while the phrase was ambiguous. — Philosophim
How, in your mind, does possible worlds semantics establish extensionality for modal logic? — Metaphysician Undercover
Not really. Although this topic is not of any particular interest to me, beyond the misuse of philosphy of language I've been pointing out.Banno, are you bored? — Philosophim
you did say:You know I never stated an essential meaning for woman — Philosophim
And that's specifically what I addressed. Again,I'm claiming the context of 'woman/man' unmodified is most rationally interpreted to mean 'sex of the person' — Philosophim
Insisting on only the biological sense is a misunderstanding of how language works, not a logical or empirical requirement. — Banno
And I pointed out that it is polysemous rather than ambiguous. You conflate the two....my conclusion was that the phrase is ambiguous — Philosophim
Is this kind of like how "sick" "means" "impressive" and "hot" "means" "attractive" and/or "stolen", etc.? — Outlander
Not at all. We went through this. There is no "context of 'woman/man' unmodified", no "true" meaning for such terms, beyond your preference for choose a "true" meaning in order to justify your claims concerning trans folk.I'm claiming the context of 'woman/man' unmodified is most rationally interpreted to mean 'sex of the person', not 'gender of the person.' That's what the 'trans' and 'cis' modifiers are for. — Philosophim
So are transwomen women? Are transwomen men? No. The terms man and woman indicate a person's age and sex, not gender. Are transwomen men who act with a female gender? Yes. Are transmen women who act with a male gender? Yes. — Philosophim
Not quite. It's not that "possibly, Algol might not have been one of John's dogs" does not refer to anything - it clearly does. It's that substitution, the very core of extensionality, might not preserve the truth of such sentences. In modal contexts, knowing what something ‘actually is’ is not enough to determine truth; you have to consider how it might be in other possible worlds.So when we say modal logic wasn't extensional, it's that the items mentioned in modal expressions didn't pick out anything in the world. — frank
To say historically implies that it is a practice put in place. — L'éléphant
Of course this is true since all dogs are mammals. In no possible world does is there a dog that is nto a mammal.(5) Necessarily, all John's dogs are mammals: □∀x(Dx → Mx),
But he might have had a pet lizard.(6) Necessarily, all John's pets are mammals: □∀x(Px → Mx)
