Or, to switch examples, even if you and I don't mean the very same colour when we say "red" - if your red is my blue - we will both stop at the red light. — Banno
Is it just me, or oughtn't everyone here (and on similar threads) to clarify which of these two related but separable questions they are addressing?
• is my external red the same as your external red?
• is my internal red the same as your internal red? — bongo fury
A place where we see a more trivial side of ontological relativity is in the case of a finite universe of named objects. Here there is no occasion for quantification, except as an inessential abbreviation; for we can expand quantifications into finite conjunctions and alternations. Variables thus disappear, and with them the question of a universe of values of variables. And the very distinction between names and other signs lapses in turn, since the mark of a name is its admissibility in positions of variables. Ontology thus is emphatically meaningless for a finite theory of named objects, considered in and of itself. Yet we are now talking meaningfully of such finite ontologies. We are able to do so precisely because we are talking, however vaguely and implicitly, within a broader containing theory. What the objects of the finite theory are, makes sense only as a statement of the background theory in its own referential idiom. The answer to the question depends on the background theory, the finite foreground theory, and, of course, the particular manner in which we choose to translate or imbed the one in the other. — Quine: Ontological Relativity
The only tenable attitude toward quantifiers and other notations of modern logic is to construe them always, in all contexts, as timeless. — Quine: Mr Strawson
As you like, it's just that math never uses quantifiers that range over even all mathematical objects, — Srap Tasmaner
The existential proposition can be expressed with bounded quantification as
∃x∈D P(x)
or equivalently
∃x (x∈D & P(x)) — Wikipedia
A [..] natural way to restrict the domain of discourse uses guarded quantification. For example, the guarded quantification
For some natural number n, n is even and n is prime
means
For some even number n, n is prime. — Wikipedia
quantification in the restricted way math does. — Srap Tasmaner
∃x (x∈R, f(x) = 0) — SophistiCat
∃x∈R ( f(x) = 0) — SophistiCat
(a) what are we talking about? — Srap Tasmaner
The only thing that all chairs have in common is that we call them all "chairs". — creativesoul
I might remark, 'Listen to those dogs howling.' If someone else tells me, 'Those aren't dogs; they're coyotes,' they're not telling me I assigned the wrong predicate to an object, they're telling me I picked the wrong sortal. — Srap Tasmaner
the main error seems to be picking the wrong collection of individuals to consider attributing "howling" to. — Srap Tasmaner
that what I'm calling "sortals" here might be how we specify the domain for our variables on the fly. — Srap Tasmaner
the plain language of that sentence ("I thought the coyotes were dogs") is ludicrous. — Srap Tasmaner
What makes me uncomfortable about the predicate calculus — Srap Tasmaner
Are you just concerned about (not) making metaphysical commitments when we write formulas?
— SophistiCat
Yes. — Pfhorrest
But, the million dollar question is, Does the existential quantifier, ∃, need to make a distinction between fact and fiction?
— TheMadFool
No. — bongo fury
tl;dr: 'Everything is a unicorn' and 'Something is a unicorn' both commit you to there being unicorns. 'Nothing is a unicorn' doesn't. — Srap Tasmaner
I simply answered the question as given, and do not know what specific part of the hard problem you feel neuroscience cannot answer. — Philosophim
So by the time we get to asserting all of modern science every time you ask for the salt, you'll still be fine, because holism, right? — Srap Tasmaner
you don't mean the same thing I do by "assert". — Srap Tasmaner
I'd be thrilled if anyone in this thread were prepared to dissolve statements, assertions, beliefs, propositions and truths into one colour — bongo fury
But does anyone think that, in saying "A dog is barking", you are asserting the existence of dogs? — Srap Tasmaner
You're assuming or presupposing there are dogs, and so far as that goes you are committed to the existence of dogs, in Quine's sense. — Srap Tasmaner
(Math doesn't suffer from this weirdness — Srap Tasmaner
It's not like when you conclude that there is a point within this interval such that ..., you are asserting the existence of points, whatever that would even mean.) — Srap Tasmaner
The "for all", universal quantifier never makes an existential assertion. — TheMadFool
why does the particular statement, "some A are B", ∃x(Ax & Bx) have to be translated as "there exists something that is an A and a B"? — TheMadFool
But the configuration of prefixes '~∀x~' figures so prominently in subsequent developments that it is convenient to adopt a condensed notation for it; the customary one is '∃x', which we may read 'there is something that'. — Quine, Mathematical Logic
Meinongian quantifiers — Srap Tasmaner
If I write "This Dodo is brown" it's logical equivalent is ∃x(Dx & Bx) but we know Dodos are extinct and the logical translation of that is ~∃x(Dx) — TheMadFool
But, the million dollar question is, Does the existential quantifier, ∃, need to make a distinction between fact and fiction? — TheMadFool
The word "exists" has a metaphysical meaning — TheMadFool
Statement 3 makes an existential claim i.e. unlike statement 2, statement 3 asserts that unicorns exist but that's not true — TheMadFool
Clearly, ∃x translated as "there exists..." is an issue. — TheMadFool
Both quantification functions, ∃ and ∀, only specify how many values of the variable they quantify make the statement that follows true, — Pfhorrest
and the statement doesn't necessarily have to be asserting the existence of anything, — Pfhorrest
But there just is no fact of the matter whether a word or picture is pointed at one thing or another. No physical bolt of energy flows from pointer to pointee(s). So the whole social game is one of pretence. — bongo fury
I am opposed to abortion but do not think the state should decide. — NOS4A2
To think, to legislate, to act with intelligence, one has to draw a line — unenlightened
But my question was really about what point the whole sentence was intended to make. — Janus
A nominalist suspects that the motivation is a mystical fascination with abstractions (e.g. "the cat's being on the mat") and the possibility of grasping them; — bongo fury
A calculator understands maths in much the same way as the room in the Chinese Room analogy understands chinese. — Malcolm Lett
It has some non-negligible understanding of the maths that it's programmed to work with. — Malcolm Lett
If it had no understanding, then it wouldn't suffice as a calculator. — Malcolm Lett
The explanatory gap is what a mechanical conception of nature creates. — apokrisis
Hence why biologists and neuroscientists are arriving at semiotics as an alternative conception of nature. — apokrisis
I'm going to muddy the waters a bit. — Srap Tasmaner
Bare unspoken sentences that implicitly assert themselves are quite handy for doing logic, of course. — Srap Tasmaner
Arguably, no statement is ever entirely bereft of any illocutionary force, and [such that it?] might be considered a "dud ticket". But we use them quite routinely when doing logic, so I'm not too concerned about that.
— Banno
Great, and when you do logic, aren't you writing (or uttering) tokens, and excluding or contextualising (e.g. attaching "not" tokens to) contradictory ones, from within a system of proliferation of assertive tokens? — bongo fury
What did you mean by "Nowt (presumably "not"?) so abstract as 'semantic content'"? — Janus
Janus
Even taking "proposition" as a term of art, it's not at all clear that this is what we ascribe truth to. Some concept of force, and in particular assertoric force, seems to be required. — Srap Tasmaner
There is a distinction between the statement "there is a fire in the next room" and the assertion "there is a fire in the next room.
— Banno
The second is a sentence token having, like a money token, currency and value in a system of interpretation. As such, within that system (of interpretation and production of sentence tokens as assertions), it is licence to produce more tokens, with similar value.
The first, if not an assertion, is outside the system - a dud ticket, a void note, an invalid vote. — bongo fury
I haven't said semantic content is "abstract". — Janus
More modestly I would say that a proposition is the semantic content of some sentences or statements. — Janus
Yes, of course, obviously the meaning of words, what they refer to, is established by convention, by praxis. How else? — Janus
You're misunderstanding; I am not promoting platonism. — Janus
The logic behind what I said is simple; the same proposition can be expressed in many different sentences, and when we say a sentence is true the meaning of 'sentence' as 'proposition' is the appropriate one. No platonism required. — Janus
A sentence is just a string of words; how could a string of words be true or false? — Janus
I think it is more in keeping with what is commonly meant to say that sentences express propositions, and that it is propositions which may be true or false. — Janus
the immediate connection between the Liar Paradox and the incompleteness theorems — Kornelius
by predicating 'not true' of itself, the Liar claims to be a member of the class of sentences that are true or false, and perhaps it is this claim that turns out to be false, making the conjunction of its claims false. — Srap Tasmaner