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diff --git a/alt/conventional-truth.markdown b/alt/conventional-truth.markdown | |
index b0f7256..9121d97 100644 | |
--- a/alt/conventional-truth.markdown | |
+++ b/alt/conventional-truth.markdown | |
@@ -1,15 +1,14 @@ | |
--- | |
-title: "There’s nothing special about conventional truths" | |
+title: "Containing Conventionalism" | |
author: "Alex Dunn" | |
--- | |
# Introduction | |
-Quine's attack on the idea of truth by convention [-@quine1966] is | |
-specifically an attack on the idea that *logical truths* are true by | |
-convention. He accepted that there might be conventional truths, and | |
-merely tried to show that mathematical and logical truths are not | |
-among them. Quine's argument is that if the infinity of mathematical | |
+The doctrine of truth by convention has been in decline for over half | |
+a century. The most important early objections came from Quine, but | |
+they were limited to is the idea that *logical truths* are true by | |
+convention [-@quine1966]. In brief: if the infinity of mathematical | |
and logical truths are all conventional, there has to be some *general | |
rules* to generate them all [@quine1966]. One rule might be "for any | |
$P$ and $Q$, if '$P$' is true and 'if $P$, then $Q$' is true, then | |
@@ -23,13 +22,34 @@ which is *not* conventional. And since the "if" and "then" of that | |
pre-existing language are not conventional, logical truths expressed | |
using *them* will not be conventional truths. | |
-But Quine concedes more than he needs to. I'm going to present a | |
-*general* objection to the notion of conventional truth. Instead of | |
-arguing that a particular class of truths (like those of logic) aren't | |
-conventional, I'm going to argue that there just *are no conventional | |
-truths.* | |
- | |
-## What is conventional truth, and why do we want it? | |
+This was a major blow, because the whole reason philosophers were | |
+drawn to conventional truth in the first place was to explain how we | |
+can know logical truths, mathematical truths, and conceptual truths *a | |
+priori*. | |
+ | |
+Some conventionalists were content to retreat to the far more modest | |
+claim that conventional *versions* of the non-conventional logical | |
+truths can be introduced *using* them; someone who introduced an | |
+artificial language could know *its* truths *a priori*. | |
+ | |
+But there is a further, general objection to the notion of | |
+conventional truth which has become widely accepted in recent years. | |
+If a sentence $S$ is *stipulated to be true,* what does it mean? What | |
+proposition does someone sincerely uttering it express? If $S$ is | |
+introduced to be true no matter what the world is like, then how can | |
+it be used to say anything at all? | |
+ | |
+There is one possible definition of conventional truth that avoids | |
+these objections, but it is a further weakening of the doctrine. The | |
+last refuge of the conventionalist is to define "conventional truth" | |
+as "something the truth of which is explained by convention(s)." The | |
+weakness is because, I'll argue, whether something explains something | |
+else is relative to an audience and a context. If such conventional | |
+truths can be known *a priori,* therefore, it will only be by *some* | |
+people at *some* times. It's not clear that this is still a doctrine | |
+worth defending. | |
+ | |
+# What is conventional truth, and why do we want it? | |
There are a few different things people mean by "conventional truth": | |
something that's *made true* by a convention, something that's true | |
@@ -58,11 +78,14 @@ Minaj is a musician? | |
This is an epistemological problem, so the solution will start and end | |
in epistemology. One epistemological solution is to suggest that we | |
"perceive" the truth of mathematical and logical facts by means of | |
-some faculty of "intuition". | |
+some faculty of "intuition". But, arguably, "no one has succeeded in | |
+saying what this faculty really is nor how it manages to yield the | |
+relevant knowledge. 'Intuition' seems like a name for the mystery we | |
+are addressing, rather than a solution to it" [@boghossian2000 231]. | |
-The notion of conventional truth was developed as an | |
-alternative to that solution. This alternative is what Paul | |
-Boghossian calls the "analytic explanation": | |
+The notion of conventional truth was developed in response to the | |
+shortcomings of "intuition". The doctrine of conventional is part of | |
+what Paul Boghossian calls the "analytic explanation": | |
> The central impetus behind the *analytic* explanation of the a | |
> priori is a desire to explain the possibility of a priori knowledge | |
@@ -89,7 +112,8 @@ does grasping the meaning of "$2 + 2 = 4$" suffice to justify our | |
belief? Why is that enough? | |
It's at this stage that certain metaphysical theses have been added to | |
-the solution to fill this explanatory gap. | |
+the solution to fill this explanatory gap, most notably the doctrine | |
+of conventional truth. | |
One such metaphysical thesis is that the truth of mathematical and | |
logical sentences (or the truth of the propositions expressed by | |
@@ -111,12 +135,7 @@ the oddness well: | |
> | |
> How could the mere fact that $S$ means that $p$ make it the case that | |
> $S$ is true? Doesn't it also have to be the case that $p$ | |
-> [-@boghossian1960 364]? | |
- | |
-Boghossian also cites Gilbert Harman, who points out that even | |
-"tautologies" such as that *I am myself* depend for their truth on | |
-facts about the world—in this case, the fact that all things are | |
-self-identical. | |
+> [-@boghossian1996 364]? | |
I think this objection is ultimately correct, but it's worth | |
describing the situation in a bit more detail. Rudolf Carnap and | |
@@ -160,6 +179,20 @@ sentence without reference to the world and then use it to express | |
something---a proposition---which necessarily says something about the | |
world. | |
+This is true even for "tautologies" such as "I am myself" and "all | |
+cats are cats." These also depend for their truth on facts about the | |
+world—in the first case, the fact that all things are self-identical, | |
+and in the second the fact that for all $x$, if $Fx$ then $Fx$. It's | |
+true that "all cats are cats" is true in part because of language | |
+conventions governing the meanings of the constituent terms---it | |
+wouldn't have been true if "all" meant "no"---but once the meaning is | |
+fixed there's the further question of whether the proposition an | |
+utterance of it, meant literally, expresses. If it's not also true | |
+that *all cats are cats,* then "all cats are cats" isn't true. And | |
+whether all cats are cats has nothing to do with convention. All cats | |
+are cats because of the general logical truth that for all $x$, if | |
+$Fx$ then $Fx$. (And that's not true by convention either.) | |
+ | |
If one replies that not all propositions say things about the world, | |
and so need not depend on facts for their truth; I think then we would | |
be disagreeing over what a proposition is. A "conventional truth" the | |
@@ -178,7 +211,7 @@ $A$ is sometimes sufficient to know that you will do or even are doing | |
$A$, having an intention to use a sentence $S$ in such a way that it's | |
true may be sufficient to know that $S$ is true: "in intending to use | |
my terms in such a way that $S$ is true, given the way I am using my | |
-temrs, I know directly that $S$ is true, given the way I am using my | |
+terms, I know directly that $S$ is true, given the way I am using my | |
terms" [@harman1996 393]. | |
There are some things that we can know we are doing (or are going to | |
@@ -213,7 +246,7 @@ something true without knowing whether the world is as I say it is. | |
These considerations, expressed so well by Boghossian, in fact | |
undermine his own notion of "implicit definition" with which he tries | |
to develop a non-conventional explanation of how we know logical | |
-truths *a priori.* I believe that it is simply conventionalism in | |
+truths *a priori.* I believe that it is simply Conventionalism in | |
disguise: | |
Implicit definition | |
@@ -232,7 +265,7 @@ the world is like. | |
Boghossian appeals to Kripke's example of the meter-stick in order to | |
claim that his "implicit definition" is legitimate in a way that | |
-conventionalism is not: | |
+Conventionalism is not: | |
> To help us think about this, consider Kripke's example of the | |
> introduction of the term "meter". As Kripke imagines it, someone | |
@@ -242,7 +275,7 @@ conventionalism is not: | |
> 1. Stick $S$ is a meter long at $t$. | |
> | |
> Suppose that stick $S$ exists and is a certain length at t. Then it | |
-> follows that "meter" namees that length and hence that (1) says that | |
+> follows that "meter" names that length and hence that (1) says that | |
> stick $S$ is that length at $t$, and since it is that length at $t$, | |
> (1) is true. | |
> | |
@@ -264,7 +297,7 @@ priori* truth if introduced this way. And to instead say something | |
like "'Stick $S$ is a meter long at $t$' is true at this world and all | |
those where $S$ is a meter long" would be to presuppose a meaning for | |
"meter" in the process of defining it---the same mistake Quine found | |
-in the original conventionalism. | |
+in the original Conventionalism. | |
Only certain sentences seem to work as "implicit definitions" of | |
constituent terms. In Boghossian's word, only some are | |
@@ -274,13 +307,15 @@ implicit definition at all, but the use of a sentence *non-literally* | |
to perform an *explicit* definition. Suppose I want to introduce the | |
term "floop". I say to you "this book is one floop thick." I am not | |
using the sentence literally because "floop" is not yet part of your | |
-ideolect, and I know that. Nor do I mean to stipulate that the | |
-sentence I uttered is true. What I mean is instead something like | |
+ideolect, and I know that (it surely violates some conversation maxim | |
+to use a term that I know my audience doesn't understand, without | |
+first providing them a definition). Nor do I mean to stipulate that | |
+the sentence I uttered is true. What I mean is instead something like | |
"let 'floop' designate the thickness of this book." | |
## One last try | |
-The major issue for conventionalism was the idea that a sentence could | |
+The major issue for Conventionalism was the idea that a sentence could | |
be declared true, without reference to the world that makes it so. | |
This, however, suggests a way forward---though it is a bit desperate. | |
The problem for conventional truth as I've presented it is that it | |
@@ -298,17 +333,18 @@ corresponding convention exists; and how could that be known *a | |
priori?* | |
Maybe it's possible for someone to know a conventional truth *a | |
-priori* if they themselves institute the convention. If *I* stipulate | |
-that *S* is true, then how can I fail to know that I've done so? On | |
-this line of thought, conventional truths are contingent *a priori* | |
-truths. They arise by stipulation, just as do the contingent *a | |
-priori* truths discussed by Kripke in *Naming and Necessity*. | |
- | |
-This explaination of why conventional truths are *a priori* has an | |
-obvious problem: only the person who stipulates a conventional truth | |
-can know it *a priori*. Just as it's only *a priori* for whoever | |
-performs the "dubbing" that this bar is a meter long, so it's only *a | |
-priori* for whoever makes the stipulation that some *S* is | |
+priori* if they themselves institute the convention. If *I* introduce | |
+the convention that makes *S* true, then how can I fail to know that | |
+I've done so, and therefore also that $S$ is true? On this line of | |
+thought, conventional truths are contingent *a priori* truths. They | |
+arise by stipulation, just as do the contingent *a priori* truths | |
+discussed by Kripke in *Naming and Necessity*. | |
+ | |
+This explanation of why conventional truths are *a priori* has an | |
+obvious problem: only the person who performs the stipulation can know | |
+the corresponding truth *a priori*. Just as it's only *a priori* for | |
+whoever performs the "dubbing" that this bar is a meter long, so it's | |
+only *a priori* for whoever performs the stipulation that *S* is | |
(conventionally) true. | |
This is unfortunate, but it's not unique to my version of | |
@@ -365,9 +401,6 @@ priority. Let's assume, then, that *if* there are truths that are | |
true because of, or in virtue of, a convention, then they can be known | |
*a priori*. | |
-The rest of this paper will be arguing that the antecedent of that | |
-conditional is false. There aren't any truths of that sort. | |
- | |
# Three proposed definitions | |
1. Conventional truths are *made true by* conventions; | |
@@ -397,9 +430,10 @@ If this division is correct, then we have two questions to answer: | |
2. Is a conventional truth something the truth of which is *explained* | |
by (the existence of) a convention? | |
-My answer to both will be "no"; and if there are no better candidate | |
-definitions for "conventional truth", then the upshot is that there | |
-probably aren't any. | |
+My answer to the first will be "no". My answer to the second will be | |
+"only in some contexts". If there are no better candidate definitions | |
+for "conventional truth", then the upshot is that whether something is | |
+a conventional truth is a relative affair. | |
# Entailment relations | |
@@ -413,7 +447,7 @@ In this section I need to do two things: | |
is entailed by (the existence of) a convention" can't work as a | |
definition of "conventional truth." | |
-### *is made true by* $=$ *is entailed by* | |
+## *is made true by* $=$ *is entailed by* | |
This section won't be entirely conclusive; the best I can do is | |
explain why I think that these relations are identical, and address | |
@@ -532,9 +566,9 @@ difference between conventional and other truths. The problem was | |
that it boils down to nothing more than first-order logical | |
entailment; we need something more robust. The relation of *is true | |
because of,* or, equivalently, *is true in virtue of,* might better | |
-serve our purpose. (Spoiler: I don't think it will.) | |
+serve our purpose. | |
-Again I've got two tasks: | |
+I'll be doing two things in this section: | |
1. Justify my claim that the *is true because of* and *is true in | |
virtue of* relations are the same explanatory relation; and | |
@@ -542,8 +576,10 @@ Again I've got two tasks: | |
2. Show the following: being explained by (the existence of) a | |
convention is not what makes conventional truths special, and so | |
why "truth which is explained by (the existence of) a convention" | |
- can't work as a definition of "conventional truth," at least not if | |
- we want there do be conventional truths *full stop.* | |
+ can't work as a definition of "conventional truth"---at least not | |
+ if we want there do be conventional truths *full stop*. But it may | |
+ be the conventionalist's only option to accept a notion of | |
+ conventional truth that's relative. | |
## "because of" and "in virtue of" | |
@@ -588,7 +624,7 @@ explain why a given conventional truth is true. | |
But whether or not this proposal is true depends on what an | |
explanation is. | |
-## What's an explanation? | |
+## What explanation isn't | |
The classic deductive-nomological theory treats explanations as a | |
subset of entailments. A deductive-nomological "explanation" as to why | |
@@ -611,10 +647,13 @@ Carla has not become pregnant: | |
4. Therefore, Carla has not become pregnant. | |
Carla has failed to become pregnant not because she's taking birth | |
-control, but because she doesn't have a womb. *That's* the relevant, | |
-explanatory bit of information, but the deductive-nomological model | |
-treats all laws as (equally) explanatory, at least with regard to | |
-deductions that they're essential to. | |
+control, but because she doesn't have a womb. "Nobody without a womb | |
+becomes pregnant" is a more explanatory law on account of its | |
+increased generality and lack of irrelevant information, but the | |
+deductive-nomological model treats (3) as equally explanatory. Indeed | |
+it treats *all* laws that are essential to these deductive-nomological | |
+"explanations" as explanatory to the same degree, ignoring the role | |
+that relevance plays in determining explanatoriness. | |
Another problem for the deductive-nomological theory is that the | |
"explanations" it produces are symmetric. For example, both of the | |
@@ -719,18 +758,20 @@ says that something is explanatory just to the extent that it's | |
indicative of the content of an ideal text. That's not what | |
"explanatory" actually means, and we can see this when we see that | |
this is a perfectly sensible question: *what if the ideal text is not | |
-explanatory?* Railton is committed to the answer to this question | |
-always being "no," *by definition*. But it's not, because | |
-"explanatory" does not mean what he thinks it means, and an | |
-explanation is not what he thinks it is. | |
+explanatory?* Railton is committed to the answer to this question | |
+always being "no," *by definition*. But it's not, because as we've | |
+seen *relevancy* is an essential part of the meaning of | |
+"explanation"---and Railton's ideal text might not be relevant in all | |
+situations. Ultimately, "explanatory" does not mean what he thinks it | |
+means, and an explanation is not what he thinks it is. | |
*Explanations are aids to understanding*. If what I say does not help | |
- you understand why $p$, I have not explained $p$ to you. Railton | |
- abstracts away from the fact that explanations are *offered* from one | |
- person to another. By treating them as abstract objects that could | |
- theoretically exist in a world with no people at all, he loses sight | |
- of what is constitutive of explanations: their role in aiding *our* | |
- understanding. | |
+you understand why $p$, I have not explained $p$ to you. Railton | |
+abstracts away from the fact that explanations are *offered* from one | |
+person to another. By treating them as abstract objects that could | |
+theoretically exist in a world with no people at all, he loses sight | |
+of what is constitutive of explanations: their role in aiding *our* | |
+understanding. | |
## Explanations are aids to understanding | |
@@ -748,7 +789,7 @@ because it doesn't help you understand why cats have tails. | |
***** | |
-Jeb Lund recently proposed a revisionary definition of "sandwich" in | |
+Last year Jeb Lund proposed a revisionary definition of "sandwich" in | |
the *Guardian* such that when he says "a hot dog is a sandwich," what | |
he says (or at least what he means) is true. His definition of | |
"sandwich" is "a portable, relatively tidy meal inside a bread | |
@@ -847,13 +888,13 @@ people's interests, *nothing* is an explanation *full stop*. | |
## An objection | |
-We may have gone slightly astray, however, because "a hot dog is a | |
-sandwich" is not actually a conventional truth in the sense we're | |
-interested in. It's what Quine would call a "truth definitionally | |
-abbreviated" [-@quine1966 72]. Lund, by defining "sandwich" as | |
-"portable, relatively tidy meal inside a bread conveyance," has | |
-introduced a convention of abbreviation: "sandwich" simply | |
-*abbreviates* "portable, relatively tidy meal inside a bread | |
+I used the hot dog example because it is nice and straightforward, but | |
+of course "a hot dog is a sandwich" is not actually a conventional | |
+truth in the sense we're interested in. It's what Quine would call a | |
+"truth definitionally abbreviated" [-@quine1966 72]. Lund, by | |
+defining "sandwich" as "portable, relatively tidy meal inside a bread | |
+conveyance," has introduced a convention of abbreviation: "sandwich" | |
+simply *abbreviates* "portable, relatively tidy meal inside a bread | |
conveyance" as a result of this definition. And all a definition | |
does, as Quine pointed out, is to *transmit* truth [-@quine1966 71]. | |
If "a hot dog is a portable bread meal" is not (already) true, then "a | |
@@ -924,8 +965,8 @@ not involve any particular convention. Therefore $\ulcorner$If $P$ | |
and $P \rightarrow Q$, then $Q\urcorner$ is *not* a conventional truth | |
*full stop*. And it seems to me that there is no such thing. | |
-Corey McGrath offers one last-ditch attempt to salvage the notion of | |
-conventional truth: | |
+Corey McGrath offers one last-ditch attempt to salvage a notion of | |
+conventional truth (full stop) in terms of explanation: | |
- $\ulcorner P$ is a conventional truth$\urcorner$ $=_{df}$ | |
$\ulcorner$it is impossible to explain to someone *who does not know | |
@@ -939,19 +980,87 @@ definitionally abbreviated. Adopting definitional abbreviations (even | |
if that is a conventional process) does *not* produce conventional | |
truths. | |
+# The last hope for Conventionalism: relativity | |
+ | |
+As unappealing as the idea will be to many, it may be possible to | |
+salvage the notion of conventional truth as a relative thing. $S$ | |
+might then be a conventional truth for me, but not for someone else. | |
+ | |
+This is not as disastrous as it seems, when we take into consideration | |
+how much the conventionalist has already given up. Remember that | |
+Geoffrey Hellman was already compelled, by the force of Quine's | |
+criticisms, to limit conventional truths to the domain of artificial | |
+language. It was already true, then, that the *a priori* knowledge | |
+provided by apprehension of conventional truths was limited to those | |
+engaged in explicit stipulation. | |
+ | |
+I admit that it's not yet clear to me what truths could be explained | |
+by (the existence of) a convention and also known *a priori.* We | |
+*want,* of course to be able to include (artificially stipulated) | |
+logical truths in this group. However, that will first require | |
+stipulating conventional versions of the logical connectives, and I'm | |
+not sure how that is possible in the case of some, including $=$. How | |
+do we define a "$=^{*}$" such that our justification for believing | |
+propositions involving it does not ultimately trace back to our | |
+knowledge of $=$? For example, I cannot see how Hellman's attempt is | |
+satisfactory: | |
+ | |
+> Self-identity is a paradigm example of what I would call a | |
+> "stipulated universal trait": we introduce "$=$" (or can: if anyone | |
+> insists that the symbol "$=$" already has another use, we choose a | |
+> new symbol, "$=^{*}$") by stipulating that, in any context whatever, | |
+> including all modal and counterfactual contexts, "$=$" ("$=^{*}$") | |
+> holds just between any object and itself [-@hellman1998 194]. | |
+ | |
+When it comes time to evaluate whether $x =^{*} y$, what do we do? | |
+The instruction provided by our definition of "$=^{*}$" is more or | |
+less "are they *really* identical?" The buck gets passed back to the | |
+original, non-conventional $=$: we're only justified in believing that | |
+$x =^{*} y$ if we're also justified in believing that $x = y$. | |
+ | |
+This is not to deny Hellman's point from earlier, that the | |
+conventionalist can be satisfied with defining the conventional in | |
+terms of the non-conventional: | |
+ | |
+> Here what is at stake is whether knowledge of language suffices for | |
+> knowledge of the soundness of logical rules. (Since the rules govern | |
+> the logician’s regimented language, that is the one that is | |
+> relevant, of course.) It is quite irrelevant that the satisfaction | |
+> conditions cannot serve the purposes of first language acquisition | |
+> [-@hellman1998 199]. | |
+ | |
+As he admits, it's not enough to define "$=^{*}$" in terms of "$=$". Our | |
+knowledge of the soundness of "$=^{*}$" must be based in knowledge of | |
+language. But as far as I can tell, using his definition, it's not. | |
+Rather, it's based in metaphysical facts about identity. | |
+ | |
# Conclusion | |
-The claims I've made, and tried to defend, are these: | |
+This, then, is the corner we've driven Conventionalism into: | |
+ | |
+- Quine showed that the justification for our beliefs about logic, | |
+ math, etc., is not based in convention unless we introduce | |
+ artificial versions of the logical and mathematical terms "on top | |
+ of" the original, non-conventional ones. | |
+ | |
+- To simply stipulate that some sentence $S$ is true does not yield | |
+ anything that can be used to express a proposition. "Conventional | |
+ truths" as commonly conceived are incapable of being really true | |
+ *or* false because (by design) they say nothing about the world. | |
+ | |
+Our novel solution of defining "conventional truth" as something | |
+made true by or true in virtue of a convention is a poor alternative: | |
- We cannot identify what's special about conventional truths by | |
appealing to the entities (states of affairs, or facts, or tropes) | |
that entail them. | |
-- We can't appeal to the facts that *explain* them either, because | |
- there are no explanations in isolation---something is an explanation | |
- only in a context, which includes individuals and their interests. | |
- "A hot dog is a sandwich" is true because of a conventional fact in | |
- one context (when the explanation refers to the convention of using | |
+- We can't motivate a non-relative notion of conventional truth by | |
+ appealing to the facts that *explain* them either, because there | |
+ are no explanations in isolation---something is an explanation only | |
+ in a context, which includes individuals and their interests. "A | |
+ hot dog is a sandwich" is true because of a conventional fact in one | |
+ context (when the explanation refers to the convention of using | |
"sandwich" with a stipulative meaning), but is true because of | |
non-conventional facts in other contexts (when the explanation | |
refers to the physical properties of a hot dog). Even | |
@@ -963,10 +1072,11 @@ The upshot seems to be that the closest thing we can do is define | |
"conventional truth" as "truth explained by (the existence of) a | |
convention," a definition which results in truths being convention in | |
some contexts and not in others. "Conventional truths" in this sense | |
-cannot solve the epistemological problem that they were introduced to | |
-solve. | |
+may be able to ground *a priori* knowledge in a limited way, but there | |
+are immediate obstacles to this approach as well. It may be finally | |
+time to give up on conventional truth. | |
\section*{Acknowledgments}\label{acknowledgments} | |
-Many thanks to Corey McGrath for conversation and references on this | |
-topic. | |
+Many thanks to Corey McGrath and Juliana Lima for conversation and | |
+references on this topic. |
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