There is likely a missing premise that you cannot articulate, — The Great Whatever

I think there indeed is an additional premise that Michael is successfully articulating but that you keep ignoring, for some reason. The additional premise is that the languages of the used sentence and of the mentioned sentence are the same. When this additional premise, which amounts to a range restriction on the identity of the languages relied on to understand the sentences, is provided, then Michael's biconditional is true. The only trouble that was apparent to me was his earlier reliance on this biconditional to support some contentious counterfactual conditionals about, e.g., rabbits and horses.

But I think that it is possible in certain circumstances that P and not "P" is true. — Sapientia

What circumstances would that be? Remember that philosophers who employ the disquotational schema (e.g. Tarskian truth theorists, disquotationalists, deflationists, minimalists, identity truth theorists, or prosentential truth theorists) all are using it in contexts where it is assumed that the truth conditions of the mentioned sentence are determined by means of the used sentence (on the right hand side of the biconditional). Hence, circumstances where its truth conditions would be different from the truth conditions of the used sentence are ruled out. So, it's rather like I were saying that if a natural number N is smaller than 3 then,

N is prime if and only if N = 2,

And you were to object that this biconditional is false because some natural numbers are prime other than 2.

I meant it in the sense that if we think of the cat being on the mat as the truth-condition that makes "the cat is on the mat" true, and if "the cat is on the mat" refers to the cat being on the mat, then "the cat is on the mat" refers to that truth-condition.

Maybe "truth-maker" or even just "referent" is the better term? Although I guess this is largely semantic and makes no significant difference to the issue at hand. — Michael

Yes, it's true that nothing much hangs on the use of "refers to" here. But "refers to" usually is understood as a relation between singular terms and the objects that they refer to, or between concept words and the Fregean concepts (or determinations) that they refer to. In the case of whole sentences, they are said by Frege to refer to truth values, and the thoughts that they express are their senses. Knowledge of the truth conditions of sentences would be equated with knowledge of the senses that they express. One can know the sense of a sentence and not know whether it is true or not. One needs in addition to know the references (Bedeutugnen) of the terms this sentence is composed of. When this is known, then the truth value can be assessed through checking what's up with those Bedeutungen in the world (e.g. does the object referred to by the singular term have the determination referred to by the concept word?). This is why Frege locates the truth value of the sentence at the level of reference, and the meaning of the sentence (its truth conditions) at the level of sense (Fregean Sinn).

Why? The "this" is self-referential. — Michael

It's unclear because it sounds like "this" is used to single out the language you are making claims about, not to specify the language in which you've decided to write your post, or part of your post, let alone the second part of one single sentence in your post. Also, there are less confusing ways to make your point about meaning being determined by use, it seems to me.

That's why I clarified the previous example by saying:

Given that in this language "horse" means "rabbit"... — Michael

That's not sufficient. You also have to say: "... and given that I've decided to write this post in this language..."

They reference the same truth condition. So in that sense they mean the same thing, even if the cognitive content has a different focus. Consider the sentences "you are a parent" and "you have a child". The cognitive content of the first focuses on what you are and the cognitive content of the latter focuses on what you have, and yet they both reference the same truth condition and so amount to the same claim. — Michael

Yes, that is quite correct, though I would be tempted to nitpick on behalf of Frege and say that they have the same truth conditions and hence reference the same truth values in all circumstances.

It's implicit in the schema that the sentence mentioned on the one side is the same sentence used on the other side. — Michael

That depends. If it's the disquotational shema (or the homophonic case for the T-shema) that is at issue, then, yes, the sentence mentioned is the same as the sentence used (and both are interpreted in the same language). But in the T-shema derived from a Tarskian truth theory, there is no requirement that the object-language and the meta-language be the same. The meta-language has its own semantic rules fixed and is used to specify truth conditions for the sentences of the object-language. And in both cases (either the simple disquotational schema or the T-schema instanciations of some Tarskian truth theory) the interpretation of the schema instanciations as counterfactual conditionals, where the antecedent specifies some counterfactual semantic rule for the mentioned language, is incorrect.

I'm stating the T-schema where the sentence mentioned on the one side is the sentence used on the other side. So whatever language it's in, with this condition the bidirectional equivalence holds.

"X" is true iff X and X iff "X" is true. — Michael

Yes, if you settle on a specific language, whatever this language might be, then the material equivalence holds. But then it can't be interpreted as a subjunctive conditional. And you also need to indicate that, when you choose some language L different than English, then you mean your statement of specific shema instanciations to be interpreted in L rather than in English. The default is to interpret sentences that are used as being written in English (on this forum, anyway).

Again, no. This is the error. Whether a certain sentence or string of words is true or not in a hypothetical situation (not now) does not guarantee that the situation that is described by that string of words in the language as it currently is now, holds in the hypothetical situation. In the hypothetical situation, "P" might very well mean not P, and so the truth of "P" could very well imply not P, rather than P. — The Great Whatever

Obviously, you overlooked my explicit qualifier "by us". This is always assumed by the logicians and philosophers of language who make use of the disquotational shema. We are not talking about counterfactual situations where the mentioned sentence has a different meaning. We are rather talking about counterfactual circumstances where its truth value varies as a function of the way the world is in those circumstances.

It is because of this that it is the case that P does not entail that "P" is true (although it does so if certain conditions are satisfied), and that therefore, the pre-linguistic universe counterexample stands. — Sapientia

Yes, I think we can agree that in the distant past, when there weren't any language users around, and hence there were no rules governing the use of the words employed in "P", it was still the case that P. That it was the case that P can be expressed by us with the sentence "P", which is true if and only if P, right? Hence it is correct to say that the two sentences (1) "P" and (2) '"P" is true' are logically equivalent, which can be expressed thus:

"P" is true if and only if P

For instance:

"There were triceratops around 68 million years ago" (as expressed by us now) is true if and only if there were triceratops around 68 million years ago.

So, it's not really the disquotational shema in itself that is the source of Michael's trouble. (And indeed, most logicians and philosophers of language don't have any trouble with this schema, though they may disagree on their detailed accounts of truth and meaning.)

OK, so, that dinosaurs were walking the earth, although true now, was not true at the time. But now that we have judged it to be true that they were walking the earth it will be true for all time, even at some time in the future, when there are no humans? — John

No, that's not what I meant to imply. That dinosaurs were walking the Earth is both a fact and the content of a true judgment. The content of the judgment is what is shared between different people who judge this content to be true. It also can be the content of other propositional attitudes such as hopes, fears, or it can figure in more complex thought such as, e.g. being the antecedent of a conditional.

All I meant to convey rather is that, if there had been people present at the time when dinosaurs were roaming the Earth, and who would have been in a position to judge this to be the case, and who may or may not have expressed this judgment using whatever language that had sufficient conceptual resources for expressing it, those people would have been entertaining the very same thought content that we now are able to express with a past tense statement. The very same judgment expressed by them, then, can be expressed by us now. So, its being true doesn't depend on them, or us, existing at all. The content of any judgment actually entertained by someone at a specific time (i.e. its truth conditions) necessarily must be ascertained as a function of the concepts employed (reflected in the use of the words that express them) but the truth value of those judgments only depend on what is the case in the world at the relevant time (and not necessarily at the time when the thought is entertained).

I had explained this earlier in rather more details here, here and here.

... we can consider the case of how given the worldly circumstances some dessert ought to be evaluated as a red velvet cake (or not):

This is a red velvet cake iff this recipe was successfully followed.

If the above is true then the below is true.

This recipe was successfully followed iff this is a red velvet cake.

So it doesn't matter whether you explain it in terms of material or subjunctive equivalence or in terms of instructions for evaluation; it can be read in either direction. — Michael

There is a crucial disanalogy that you are overlooking. Correctly following the recipe for a velvet cake ensures the production of a velvet cake, let us assume. However, correctly following the semantic rules of a language doesn't ensure that "Smokey the cat is on the mat", when correctly evaluated to be true according to those rules, implies that Smokey the cat is on the mat. That's only guaranteed to be the case when the semantic rules are those of the English language. If they are the semantic rules for another language, then it may be the case that "Smokey the cat is on the mat" is correctly evaluated to be true according to those rules while Smokey the cat isn't on the mat.

I thought that you'd notice the difference, too. I'm glad that I'm not the only one to object to Michael's attempt to conflate the two.

I'd add that one is about that which is true (a sentence which satisfies certain truth conditions; language), whereas the other is about that which is the case (a fact or state of affairs; the world). — Sapientia

It seems to me that you and TGW may be making too much of that. Even though one sentence has an English expression as its grammatical subject, it mentions it (and refers to its meaning) as an indirect means of making a claim about what is the case in the world, whereas the other sentence makes that very same claim directly. Michael is right to point out that they are logically equivalent in that respect -- in that they logically imply one another -- assuming only that the meaning of the mentioned sentence is held fixed and taken to be its ordinary meaning in English. It is through forgetting this necessary assumption (in counterfactual contexts) that Michael sometimes run into trouble, it seems to me.

I knew that is what you would say, that you would pick the second option. I was interested to hear what Pierre would say. — John

Yes, I agree with Michael. Judgments that are true at the time when they are judged or expressed are true at all times. If one correctly judges at one time that Smokey the cat is (at that time) on the mat, then this judgment remains true at a later time when Smokey has wandered off the mat. The very same judgment (the content, not the speech act) then can be re-expressed with the use of a different 'situational sentence' that includes a verb in the past tense.

It follows from this that in all cases where "Smokey the cat is on the mat" (in English) is (or would be) true, Smokey the cat is (or would be) on the mat, and in all cases where "Smokey the cat is on the mat" (in English) is (or would be) false, Smokey the cat isn't (or wouldn't) be on the mat. — Michael

That's exactly right. But notice that it doesn't follow that in all cases where "Smokey the cat is on the mat" is (or would be) true in some other language than English, in 'New English', say, Smokey the cat is (or would be) on the mat. And yet this is what you were saying. Even though you actually meant your claim to be interpreted as if you were expressing the consequent in 'New English', this use isn't warranted by the normal interpretation of the T-shema.

(On edit: I had missed the second part of your comment, so I responded to that below)

Where does my logic fail? You say that "the cat is on the mat" would be false if the cat were not on the mat, and so we have ¬C > ¬P (using the subjunctive conditional). As per transposition this is equivalent to P > C, which is that the cat would not be on the mat if 'the cat is on the mat' would be false". — Michael

Yes that's correct so long as you hold fixed the range of actual+counterfactual (i.e. 'possible') circumstances in which the implication sign can be interpreted as material implication. Saying that P > C is equivalent to saying that in all possible worlds at which P, it also is the case that C. Hence, relative to this very same range of possible worlds, it also follows that whenever ¬C, it also is the case that ¬P. But this needs not have the same significance as ¬C > ¬P, since the range of possible worlds that ¬C singles out may be a different range. And that is indeed the case where your contentious interpretation of the T-shema is concerned. For the case where the T-shema is correctly interpreted, the relevant range of counterfactual circumstances includes, precisely, worldly circumstances (i.e. ways for things to be) relative to which the truth of object-language sentences are to be evaluated in accordance with their (indirectly) stipulated meanings. There is no ranging over other possible (i.e. non-actual) reference assignments to the object-language terms.

Hence, you are licensed to say, on the basis of the T-shema instanciation previously discussed, that in all cases where Smokey the cat is (or would be) on the mat, "Smokey the cat is on the mat" (in English) is (or would be) true, and in all cases where Smokey the cat isn't (or wouldn't be) on the mat, "Smokey the cat is on the mat" (in English) is (or would be) false. Hence, material equivalence holds relative to a specific range of circumstances. This range of possible circumstances, envisioned by the T-shema instanciation, is a range of circumstances in which Smokey is located at various places, not all of them "on" the mat. But, relative to all the possible worlds in that range, the meanings of the English words used to state the theory, and the meanings of the object-language words (which can be the same language as the meta-language) are held fixed. It's precisely because they are held fixed that the T-shema doesn't licence the ¬C > ¬P subjunctive conditional claim that you want to derive from it, where they would be allowed to vary over circumstance of linguistic use in which meaning assignments to the words of the object-language would be different than those that are intended by the specific truth theory that this T-shema instanciation is a theorem of.

Yes, and don't call me Hilary. — Sapientia

Hilary is a man, and nobody called you Putnam.

A subjunctive conditional is a counterfactual conditional, and the T-schema doesn't seem to use a counterfactual conditional. If it did (pun intended) it would look like this: — Michael

Rather than focus exclusively on what it looks like, you ought to focus a little more on how it is used. Remember that it is you yourself who introduced explicitly a contentious counterfactual conditional statement, insisted that it be read as such, and invoked Tarski's T-shema in order to justify it. My rejoinder was that you were reading the T-shema in the wrong direction.

The sort of claim that you wish to defend is:

(1) If "Smokey the cat is on the mat" is true, then Smokey the cat is on the map.

And you also insisted that your claims should be understood as counterfactual conditionals (one such claim was concerning horses, rabbits and synonymy).

It is true that (1), interpreted as a material inference, can be validly inferred from

(2) If "Smokey the cat is on the mat" is true if and only if Smokey the cat is on the map.

However, when read as a subjunctive conditional in which '"the cat is on the mat" is true' is the antecedent, (1) becomes a misrepresentation of (2) as it is intended to be read in the context of a Tarskian truth theory.

That's because instanciations of the T-shema (as derived from the meaning assignment axioms of the theory) are meant to be interpreted as a recipe, or instruction manual, that tells you how, given specific worldly circumstances (e.g. circumstances either actual or counterfactual where horses are or aren't rabbits, or where Smokey the cat is or isn't on the mat) sentences in the object language ought to be evaluated as true or false.

This is why (2) must be understood as stating the conditions under which "the cat is on the mat" is correctly evaluated, in whatever object-language is being formalized by the truth theory, rather than as stating what the conditions in the world would be (counterfactually) if the mentioned object-language sentence were true. It can't mean both, for in that case the account would be viciously circular.

But, going back to the topic, I doubt whether I'd have much to say that hasn't already been said, and probably said in a better way than I could. I found myself in agreement with yourself and Marchesk. This post earlier on made a good point, I think: — Sapientia

Yes, I agree with Marchesk, and with Searle, that an ability merely to respond to external stimulations in accordance with algorithmic rules can't, in itself, constitute understanding.

Searle, however, believes that human verbal behavior is meaningful because the intentional content of speech acts are derivative from the intentional contents of the mental acts standing behind them, and he also believes that the latter contents ("intrinsic intentionality") are an emergent biological property instantiated in some mysterious way in human brains.

I agree with Michael that this is a mistake and that the proper place to look for understanding and intentionality is the public behavior of an agent in the world; and meaning is thus best reflected in the use of linguistic expressions. I think such an agent, though, must be a living rational animal and can't be a computer. Michael may be disagreeing with this. Our long digression may have just begun to touch on some disagreement about what forms of public behavior are constitutive or expressive of genuine ("intrinsic") understanding and intentionality.

Ok, well if that's the sense in which you're using it, then fair enough. Thanks for clarifying. It makes sense to me, given your examples, although not so much with regards to references to the past, present and future. Something about that strikes me as intuitively wrong. The differences are harder to ignore. — Sapientia

I think this may clash a little bit with intuition not because it contradicts common sense but rather because it doesn't mesh well with the way propositions with empirical content are commonly treated in philosophy, and, in particular, with the use of predicate logic and tense logic. There is a tendency, in analytic philosophy, to make time figure as part of the content of empirical propositions. This is implicitly assumed when time is represented by the tense of a verb.

When time is rather understood, in a more Kantian way, not as part of the content of an empirical thought (i.e. a thought that relates directly to a possible experience) but rather as part of the form of this thought, then counterintuitiveness of the claim that the two sentences "I ate eggs this morning" and "I ate eggs yesterday morning" can express the same thought is alleviated. We have to remember that we don't perceive the time at which we perceive sensible things in addition to perceiving those things (even when there is a clock nearby). One's ability to rationally relate those two forms of expression (about eggs) is constitutive of one's ability to keep track of time and hence, also, to think temporal thoughts and grasp their logical forms. This may need to be argued more fully, but I am veering off topic. I was hoping to come back to Martha's ability (or rather, lack thereof) to genuinely express thoughts.

I am using "thought" in the same way Frege is, to signify what is thought, which is the content of an assertion expressing it. What is thought -- the content of a mental act -- can also be questioned, hoped for, feared, hypothesized, etc., and in all cases be the same thought, in that sense. Hence if you are thinking that I am 6 feet tall and I am thinking that I am 6 feet tall, we are thinking the same thought. I would be expressing this thought with the sentence "I am six feet tall", while you would express it, while addressing me, with the sentence "You are six feet tall". Those two statements make use of to different speech act forms, since one of them uses the indexical "I" while the other one uses the indexical "you". But they can express the same thought in a suitable context (that is, as uttered by two different individuals suitably related). Likewise, my statement "the grass is wet over there" could, in some context, express the same thought that you would express with the statement "the grass is wet over here". I could also express the same thought myself on two separate occasions with those two different speech act forms just through moving between the two places. The later statement ("it's wet over here") can rationally bear -- i.e. confirm -- the previous statement ("it's wet over there") just because both statement express the same thought (assuming only that they are understood to encompass the same coarsely discriminated 'present' time).

Thoughts (or judgments) that are thus kept track of through displacement in space, or through keeping track of the passage of time, are called dynamic thoughts by Gareth Evans. To be able to entertain such dynamic thoughts, and master the system of situational sentences that relate their different forms of expressions at different times (and different locations) is a condition for being able to entertain them at all. For else, one would never be able re-express the very same empirical thought at two different occasions, and one wouldn't even be able to re-affirm, or contradict, or empirically verify, or infirm, an empirical thought that one had previously entertained.

For any sentence "P", if P, then "P" is true for all cases in which "P" can be formed; and for all cases in which "P" can't be formed, then "P" would be true if it was formed. — Sapientia

You don't actually have to tie up the truth of an assertion, or of the linguistic expressions of a thought (that may have a force different than that of assertion or belief) to the circumstances that hold at the time of the utterance. One can equally say yesterday, or today, or tomorrow, in different manners, that Smokey the cat was on the mat yesterday at 11 o'clock. This very same thought would have been expressed yesterday with the situational sentence "Smokey the cat was (or is, or will be) on the mat today at 11 o'clock" or expressed the day before with the situational sentence "Smokey the cat is going to be on the mat tomorrow at 11 o'clock". This whole system of situational sentences enables one to express the same thought, with the same truth conditions, at different times, while making use of the time of elocution, in addition to the form of the speech act used, to determine the temporal thought being expressed.

Hence, one could say that, e.g.:

(1) "There were/are/will be triceratops roaming the Earth" is true iff there were/are/will be triceratops roaming the Earth.

In this case, "were/are/will be" signals the availability of a system of situatonal sentences. This means that the sentence "There are triceratops roaming the Earth" could (conceivably) have been used to express a truth 68 million years ago. But, more importantly, it also means that whatever though would have been expressed back then in that way is the very same thought that we can express now with the sentence "There were triceratops roaming the Earth 68 million years ago". Hence, the statement of the truth conditions of (the thought expressible by) a sentence doesn't require that there actually be anyone able to utter the statement at the time when its truth value is being evaluated, since we still are able to evaluate the truth of the very same thought (concerning past events) as expressed now with the use of a situational sentence that is part of the very same unitary system that allows the expression of this thought at any time.

(This is further discussed in Gareth Evans' The Varieties of Reference, under the heading of "dynamic thoughts" and in Sebastian Rödl's Categories of the Temporal, from whom I borrow the phrase "situational sentence")

There is a good critical opinion piece on CNN, written by Carolyn Shapiro, regarding Scalia's legacy, not in respect of his specific decisions, but rather in respect of his promotion of originalism (as a form of textualism).

1b) is:

(C → P) ∧ (¬C → ¬P)

Using transposition this gives us:

(C → P) ∧ (P → C)

Which is material equivalence. — Michael

Only if you insist on reading "→" to signify material implication. And this is a rather bad misconstrual of the significance of the T-shema instantiation, as I have explained. But you had suggested that the biconditional form shows that the correct reading is material implication rather than subjunctive conditional. This is a non sequitur since the fact that the statement can be written "(C → P) ∧ (¬C → ¬P)" or "(C → P) ∧ (P → C)" tells you nothing whatsoever about the significance of "→". Instead, you have to reflect a little about the pragmatic significance of the shema in the context of the truth theory it is pulled from. It is this pragmatic significance (i.e. how Tarski's truth theory is meant to be used) that recommends the subjunctive conditional interpretation, as I have explained.

I'm not sure how this makes a difference. You accept that if "X" and "Y" are synonymous then "X is Y" is true and you accept that if "X is Y" is true then X is Y. So it's a straightforward transitive relation to conclude that if "X" and "Y" are synonymous then X is Y. If the premises are true and the conclusion is a valid derivation then the argument is sound. — Michael

Yes, if, in fact (i.e. in the actual world) "X" and "Y" are synonymous, and hence have the same referent (Bedeutung) and the same Fregean sense (i.e. they have the same use in the language) then it is also true that X is Y. Hence you can say that:

(1) If "X" and "Y" are synonymous then X is Y

But this must be understood as a material implication, and not a subjunctive conditional. It says that if the antecedent is true, in the actual world, then so is the consequent. It doesn't say anything about counterfactual circumstances. (Though it might be construed as a subjunctive conditional where the antecedent ranges over epistemically possible circumstances rather than alethically possible circumstances; this would make sense if we don't actually know whether, in the actual world, the antecedent it true; that is, s/he who makes the statement doesn't know what either "X" or "Y" mean).

So, this sensible reading would seem to be sufficient to support your point that meaning is use but need no land you in a pickle where you seem committed to infer:

(2) If "X" and "Y" were (counterfactually) synonymous then X and Y would be numerically identical (even though they actually aren't numerically identical).

which is either a misuse of language or expresses a metaphysical impossibility due to the necessity of identity (argued for by Ruth Barcan Marcus and Saul Kripke). But you really don't need that in order to convey your main point, it seems to me.

It might not have been his intention but the logic of a biconditional is such that it can be read in either direction. — Michael

As I explained, just because the connective "if and only if" is used doesn't entail that the conditionals used signify material implications rather than subjunctive conditionals. In Tarski's case, it's the latter that's signified since the circumstances where the antecedent is evaluated range over all possible circumstances (and not just actual circumstances) where this mentioned string of words might be used. Both the "if" and the "only if" signify subjunctive conditionals, and both of those must be read from right to left, since we want the meaning and truth value of "the cat is on the mat" to be determined in all circumstances including circumstances where the cat isn't on the mat.

For instance, the T-shema instanciation:

(1a) "The cat is on the mat" is true iff (i.e. in all cases and only those cases where) the cat is on the mat

is equivalent to the conjunction:

(1b) "The cat is on the mat" is true if the cat is on the mat and "The cat is on the mat" is false if the cat isn't on the mat.

Those all are subjunctive conditionals and they are all meant to be read from right to left; that is, the meanings of the words used on the right hand side are held fixed for purpose of stating unvarying truth conditions meant to apply in the whole range of possible circumstances where the truth of the mentioned sentence (on the left-hand side) is to be stipulated.

This is why use of a biconditional is needed. But it doesn't really matter. You don't need to change the meaning of Tarski's T-shema in order justify your own use of it in a different context; and I think I now have a better grasp of what you are driving at.

The example I gave didn't use a counterfactual meaning. It used ordinary English. If "horses are equine animals" is true then horses are equine animals. — Michael

In that case your example doesn't have anything to do with the T-shemas that occur in a Tarskian truth theory, and so it's unclear why you attempted to rely on this notion. In the context of such a theory, a T-shema states general truth conditions for a sentence expressed in the object-language and hence has the force of a subjunctive conditional where the truth value of the antecedent is defined as true or false in all possible circumstances, accordingly, whether the condition stated in the consequent is satisfied or not in those circumstances.

Even then, that I can state the T-schema in a language other than English, e.g. French, is that I can state the T-schema in a language other than English, e.g. New English.

You can express the T-shema (and the whole truth theory this shema is derived from) in whatever language you like, including "New English". But such a T-shema tells you nothing about the meanings of the words used on the right-hand side of the shema. Those meanings are assumed to be understood by the theorist who uses the meta-language to state the truth conditions of the sentences mentioned on the left-hand side of the shema.

Also, the T-schema is biconditional so it can be read either way. We can say that "snow is white" is true iff snow is white or we can say that snow is white iff "snow is white" is true. It's an iff, not just an if.

The reason why it's a biconditional simply is because if the T-shema were rather a simple conditional such as:

(1) "The cat is on the mat" is true if the cat is on the mat,

then this would leave the truth value of "the cat is on the mat" undetermined in all cases where the cat isn't on the mat. But we want to stipulate that "the cat is on the mat" is false when the cat isn't on the mat; hence the biconditional. Tarski's intention never was to imply that truth values of object-language sentences determine what can be truly be said in the meta-language.

Which part? You agreed with 'If "horses" and "equine animals" are synonymous then "horses are equine animals" is true' in your previous post and 'If "horses are equine animals" is true then horses are equine animals' is the T-schema, which you accept. The conclusion 'therefore if "horses" and "equine animals" are synonymous then horses are equine animals' simply applies the transitive relation. — Michael

You are reading the T-shema in the wrong direction (from left to right rather than right to left) because the T-shema arises in the context of a truth theory that derives truth conditions for sentences of the object-language (mentioned in the left hand-side), and states those truth conditions in the meta-language used by the theorist -- in our case, English. Hence the meanings of the terms used on the right hand side of the biconditional are assumed to be their ordinary meanings in English. What is allowed to vary, in a range of counterfactual circumstances, isn't the meanings of the object-language sentences mentioned on the left-hand side, but rather the worldly circumstances in which their truth values are evaluated.

For instance the (homophonic) T-shema:

(1) "Snow is white" is true iff snow is white

just like the T-shema (stated in French):

(2) "Snow is white" est vrai ssi la neige est blanche

both state exactly the same thing, e.g., that the object-language (i.e. English) sentence "snow is white" is evaluated true in circumstances where snow is white and is evaluated false in (counterfactual) circumstances where snow isn't white. The T-shema is never concerned with counterfactual circumstances where the meanings of the words (of either the object- or meta-language) would be allowed to vary. On the contrary, the meanings of the terms of the meta-language are assumed to be understood and the meanings of the terms of the object-language are assigned with the use of the meta-language. (Those atomic meanings assignments to individual words actually are stated in the axioms of the Tarskian truth theory, while the T-shemas are theorems that are recursively deduced on the basis of those axioms.)

We need to know that the things we call "horses" are the things we call "equine animals". Which is to say that we need to know that we use the words "horses" and "equine animals" to talk about the same thing. And what does talking about the same thing consist of? What's the metaphysics behind talking about the same thing? I'm loathe to any interpretation that claims there's more to talking about things than behaviour, intention, and the empirical contexts that influence and measure them. How can anything else become a part of language, meaning, and understanding? This was Dummett's point.

I agree with everything in this paragraph of yours.

Has a decision been reached on what we are to read? I hate when I read the wrong thing because I was only half way paying attention. — Hanover

The reading for February was Pattern and Being by John Haugeland, but the conversation hasn't quite left the ground yet.

Apply the logic to English, where English is both mentioned and used. If "horses" and "equine animals" are synonymous then "horses are equine animals" is true. If "horses are equine animals" is true then horses are equine animals. Therefore if "horses" and "equine animals" are synonymous then horses are equine animals. — Michael

Your conditional seems to run the wrong way. It is because we know that (and only as long as we know that) horses are equine animals (assuming "are" here signifies necessary identity of extension) that the expressions designating them are synonymous. It's not the other way around. If an expression is introduced in the language as synonymous to another expression that already has a referent, then one will be able to use both expressions to make (trivial) identity claims. That's because this specific way of introducing the new word into the language (as synonymous to another one) insures that it has the same Fregean sense as the old one. But, generally, if two words that are in fact co-referential have different Fregean senses, then the fact that they are indeed co-referential is something that might need to be verified empirically; and this will not ensure synonymy unless the knowledge of the identity becomes widespread in the linguistic community and this knowledge would also be taken to be a criterion for understanding both expressions.

Now inject some Wittgenstein. If we use the words "horses" and "equine animals" in the same way then "horses" and "equine animals" are synonymous. Therefore if we use the words "horses" and "equine animals" in the same way then horses are equine animals.

If you mean "using in the same way" to imply that referents are identical then in order to know that "horse" and "equine animals" are indeed used in the same way by us, in the case where we already know how to use them, would require that we check that any horse necessarily is an equine animal and vice versa.

The "this sentence" is a recursive reference. — Michael

OK. You don't mean "recursive". You mean "self-referential". In that case, sure, if the sentence is allowed to claim of itself that it is to be understood in accordance with the linguistic stipulations stated in the antecedent, then, it is true. But it is then equivalent to the following:

(1) If "horses" and "rabbits" are synonymous in some language (that has the same syntax and verbs as English), then, in that language, "horses are rabbits" expresses a true claim.

If you would always say it that way that wouldn't invite any equivocation. But I am usure what philosophical lesson could be drawn from this trivial claim.

You need to read it like this:

Given that "horse" means "rabbit" in this language, horses are rabbits. — Michael

The above statement may be true as written in 'this language', but it is false as written in English.

Compare:

(1) Given that Germans put verbs at the end of their sentences, they sausages eat.

This is nonsense because stating a convention that applies to another language in the antecedent of a conditional doesn't entitle you to switch language mid-sentence.

I have repeatedly said that the conclusion is to be understood as speaking New English, where "horse" means "rabbit", and have repeatedly said that The Great Whatever's criticism rests on the very same equivocation which you mention - as he interprets the conclusion in English proper. — Michael

Even with the provision of this explicit disclaimer, as I explained, the counterfactual conditional statement still is nonsense since the truth of the consequent (even understood in New English) is unconditional. But what you mean to say is that it is conditional on the truth of the antecedent.

And the schema works for the New English language, where "horse" means "rabbit", since both the antecedent and the consequent are true in all circumstances. Your interpretation of the sentence in English proper is a misinterpretation. — Michael

Yes, it would work in New English as used by New English speakers. But then you have to specify in advance that, when you are stating such a shema, you are meant to be understood as speaking New English. Else you are inviting equivocation. When you say something like 'If "horse" meant the same thing as "rabbit" then rabbits would be horses' this is still nonsense in English and equally nonsense in New English since, while the consequent might be true as expressed in that language, it doesn't depend on the truth of the antecedent. From the point of view of speakers of New English, the thought expressed by them when they use the sentence "rabbits are horses" is true quite independently of any linguistic convention.

As I had suggested, properly interpreted (as Tarski meant it to be interpreted as a theorem in a recursive truth theory for a formal language), the biconditional:

(1) "Horses are rabbits" is true iff horses are rabbits

would be true, but the counterfactual (subjunctive) conditional:

(2) If "horse" meant the same as "rabbit" then horses would be rabbits

would still be nonsense. In both cases the consequent is expressed in English. The antecedent of the subjunctive conditional claim doesn't tell you in what language the consequent must be read. It rather tell you relative to which counterfactual circumstances the claim expressed (in English) in the consequent ought to be evaluated.

Do you know where he explains his change? — Michael

Renewing Philosophy, HUP, 1995, and The Threefold Chord, Columbia UP, 2001 provide useful statements of his mature philosophy.

The book Hilary Putnam, Cambridge UP, 2005, by Yemima Ben-Menahem also likely is useful but, although I own it, I haven't read it yet.

Then I still don't understand why you think that the T-schema should baffle me. — Michael

That's because the way you are reading it, as applied to the description of counterfactual linguistic stipulations (e.g. a hypothetical language as used in counterfactual circumstances) has an incidence on the meaning of the terms used on the right hand side. Hence you have a habit of saying such things as 'If "rabbits" meant "horses" then rabbits would be horses'. And you invoke Tarski's T-shema as a support for the intelligibility of this use. But the disquotational shema doesn't warrant such a use. What it warrants may be the shema:

(1) "Rabbits are horses" is true iff rabbits are horses

This homophonic shema works for the English language since both the antecedent and the consequent are false in all circumstances. But it doesn't warrant your counterfactual conditional claim.

I may have misunderstood you, but were you saying that the T-schema only works if the sentence used on the right-hand side says something true about the actual world? — Michael

They state truth conditions -- i.e. in what conditions the sentence mentioned on the left hand side is true. The sentence used on the right hand side may state something that is always false (i.e. in all circumstances). In that case the sentence mentioned on the left hand side would be false in all circumstances also. The stipulation of the truth conditions, on the right hand side, just are the stipulations of the conditions under which the sentence mentioned on the left-hand side would be true as interpreted in the object-language.

You said that the truth of the sentence used on the right-hand side is determined by facts about the extra-linguistic world and not by whatever definitions were stipulated on the left-hand side. — Michael

This is confused because the sentence mentioned on the left-hand side of the T-shema doesn't stipulate anything. Rather the whole T-shema expresses one specific consequence of a Tarskian truth theory for the object-language. The meanings of the words used on the right-hand side of the shemas are the meanings that they have in the meta-language used by the theorist in order to state the consequences of the theory. Those meanings are presupposed in the act of stating the theory. Hence they can't be affected by the stipulations expressed by the T-shemas.

So even if the words "horse" and "rabbit" mentioned on the left-hand side mean what they do now, the sentence used on the right-hand is true iff horses are equine animals, and as horses are equine animals then the sentence used on the right-hand side is true. And if it's true then the sentence mentioned on the left-hand side is also true.

I am unsure what you are trying to say. If the words ""horse" and "rabbit" mentioned on the left-hand side mean what they do now, then your T-shema would express incorrect truth conditions for sentences written (or spoken) in the English language. That's because the antecedent would be false in circumstances while the consequent is true (i.e. the actual circumstances where horses indeed are equine animals, but horses aren't rabbits).

Doesn't this then entail that the below is correct?

"Horses are rabbits" is true iff horses are equine animals — Michael

This might be true in relation to some language where "rabbits" is used to refer to what we are referring to, in English, with the phrase "equine animals". But I don't see your point. Horses still are equine animals whatever linguistic stipulations might be in use in this or whatever alternative linguistic community.

David L. Anderson - What is Realistic about Putnam's Internal Realism? — Michael

I wouldn't mind discussing that. But it's worth noting that Putnam has, meanwhile, distanced himself significantly from his earlier accounts of "internal realism" -- enough so to even repudiate the label. He has rather come to endorse a form of pragmatism, though of a different form than the social institutional pragmatism endorsed by Rorty and Brandom.