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Review
The Idea Theory
Mind Idea of a Dog Dog
Partly Resembles
Sees
Dog
Mind Idea of a Dog Dog
ConnotesDog
Mind Idea of a Dog Dog
Conventional RelationDog
Mind Idea of a Dog Dog
Conventional RelationDog
Natural Relation (Resemblance)
Mind Idea of a Dog Dog
DenotesDog
Problems for Idea/ Resemblance Theory
1. Can’t distinguish concepts and propositions.2. Resemblance is an equivalence relation, representation is not.3. Resemblance is in some ways more and in some ways less
determinate than representation.
1. Concepts and Propositions
The idea theory seems to have trouble distinguishing concepts and propositions.
Are mental pictures truth-evaluable? • If they are, then concepts aren’t ideas. • If they aren’t, then propositions aren’t ideas.
2. Resemblance as an Equivalence RelationResemblance, like identity, is an equivalence relation, meaning it’s reflexive, symmetric, and transitive:• Reflexive: for all X, X resembles X. (Everything resembles itself.)• Symmetric: for all X and Y, if X resembles Y, then Y resembles X. • Transitive: for all X, Y, and Z, if X resembles Y and Y resembles Z, then
X resembles Z.
2. Representation Is Not and Eq. Relation
Problem for the idea theory: resemblance is an equivalence relation, but representation is not. Therefore representation ≠ resemblance.
3. Pictures and Determinacy
Verificationism
Verificationist Semantics
#1. The meaning of a sentence is the set of experiences that would verify it.
#2. Observation sentences are directly connected with their verification conditions: we can immediately tell whether they are verified in any particular circumstance.
Immediate Experience
RED
PAIN
LOUD
THREE
Non-Observation Sentences
#3 All the other meaningful sentences (according to the verificationist) are defined in terms of the protocol sentences and the logical vocabulary (AND, OR, NOT, ALL, SOME, NO, etc.).
Example: Definition of ‘Arthropod’
‘That is an arthropod’ := • That is an animal • AND it has a jointed body • AND it has segmented legs
Mind Experience of a wound
Dagger
Perfectly correlates with
Experiences
“Dagger”
Mind Experience of a wound
Dagger
“Dagger”
Connotes
Mind Experience of a wound
Dagger
“Dagger”
Conventional Realation
Mind Experience of a wound
Dagger
“Dagger”
Connotes
Natural Relation (Correlation)
Mind Experience of a wound
Dagger
“Dagger”
Denotes
Too Little Is Meaningless
If you think “The Absolute is Perfect” and “God exists” are meaningless, then you probably think “Either some socks are cotton or the Absolute is Perfect” and “Either God exists or snow is purple” are also meaningless.
But the latter two clearly have conditions that would verify them.
Too Much Is Meaningless
A bigger focus of criticism, however, was that according too the verifiability criterion, too much is meaningless, including:
1. Statements about the past or future.2. Negative existentials.3. Positive universals.4. Certain positivist doctrines.
4. The Verifiability Criterion Itself
Consider the verifiability criterion: “a sentence is meaningless unless some finite procedure can conclusively verify its truth.”
If this criterion is meaningful, then it must be that some finite procedure can conclusively verify this claim.
But what procedure would that be?
The Problem
For many theoretical terms, it took years or decades after their introduction for us to discover any way of verifying claims about them.
Consider the claim: “DNA has a double-helical structure.” This claim seems to be meaningful.
The Problem
But Watson and Crick had to discover how to verify it.
The Problem
The reason we discover methods of verification, rather than stipulate them in advance, is that confirmation is theory dependent.
Our theories advance, and according to the new theories, certain experiences confirm certain phenomena.
The Problem
If our theories change, those same experiences may no longer confirm those same phenomena.
The experiences that confirm a statement shouldn’t be tied to its meaning unless we want to accept that meaning is theory-dependent.
The Problem
So positivism seems to suggest that claims about DNA, electrons, positrons, mesons, or whatever did not mean anything until we discovered ways of verifying them.
At that time we discovered their meanings.
Definitions Theory
Mind Idea of a Dog Dog
Partly Resembles
Sees
Dog
Mind Idea of a Dog Dog
ConnotesDog
Mind Idea of a Dog Dog
Conventional RelationDog
Denotation
But there’s another sense in which the word ‘dog’ means dogs (those furry smelly barking things): it applies to dogs and it’s true of dogs (and false of everything else).
Denotation involves the relation between words and the world– what words apply to/ are true of.
Mind Idea of a Dog Dog
Conventional RelationDog
Natural Relation (Resemblance)
Mind Idea of a Dog Dog
DenotesDog
Circularity
For any finite set of definitions containing only words that have definitions in the set: some word w defines w. (For example, “ambagious” defines “ambagious”)
So in order to learn what w is true of, I have to already know what w is true of.
Particular Definition Theories
The way to go then is to adopt a particular definition theory. On such an account, not every word has a definition for its meaning, only some particular subclass of all the words.
The Problem of Examples
Philosophers are fond of ‘bachelors are unmarried men.’ Why?
Because it’s really hard to find examples of definitions that work– where the defining part means the same thing as the defined part.
‘Bachelor’ isn’t even obvious (is the pope a bachelor? Are 14 year-olds?). Kinship terms and animal terms are about the only good bets.
The Causal-Historical Theory
The Mirror Universe
Secondary Qualities
Possibility of Massive Error
The Causal-Historical Theory
Let’s call that baby ‘Feynman’
FeynmanFeynmanFeynmanFeynman
The Causal-Historical Theory
Let’s call that baby ‘Feynman’
FeynmanFeynmanFeynmanFeynman
Historical Chain of Transmission
The Causal-Historical Theory
Denotation
FeynmanFeynmanFeynmanFeynman
Natural Kinds
The Causal-Historical Theory
Let’s call that thing a “tiger.”
TIGERTIGERTIGERTIGER
The Story of Madagascar
Let’s call that place ‘Mogadishu’
MadagascarMadagasceirMadagascuMadagishu
C.H. Theory Predicts
Let’s call that place ‘Mogadishu’
MadagascarMadagasceirMadagascuMadagishu
Denotation
C.H. Theory Predicts
Let’s call that place ‘Mogadishu’
MadagascarMadagasceirMadagascuMadagishu
DenotationWrong!!!
Real Denotation
Let’s call that place ‘Mogadishu’
MadagascarMadagasceirMadagascuMadagishu
Denotation
Madagascar
The “Madagascar” case illustrates a general point: the Causal-Historical Theory cannot account for unintentional meaning change.
Gareth
Saul
Saul
Gareth
Twins Switched at Birth
Now imagine it’s 73 years later and we’ve been calling one man “Saul” for 72.99 years, even though (unknown to us) he was baptized “Gareth.”
Saul
Twins Switched at Birth
TRUE or FALSE: Saul is wearing a hat.
Saul
The Use Theory
The Use Theory
The Use Theory
and
The Use Theory
and
ANDmeans
The Use Theory
followsA and B
A
A and BB
A, BA and B
AND
The Use Theory
followsA et B
A
A et BB
A, BA et B
ET
The Use Theory
same concept
ETAND
Summary of Principles
1. Words mean concepts, and “meaning” is univocal– it always means just “indication.”
2. For any word, all of its uses may be explained by a basic acceptance property: a regularity in the use of the word, that explains irregular uses as well.
3. Concepts are individuated by the basic acceptance properties of the words that express them.
Inference Rules
A tonk BB
A .
A tonk B
Proof Involving Tonk
Michael is a philosopher = AMichael is the greatest philosopher = B
1. A Premise2. A tonk B Tonk Rule #23. B Tonk Rule #1
Inference Rules
A tonk BB
A .
A tonk B
When “B” is false, “A tonk B” must be false.
Inference Rules
A tonk BB
A .
A tonk B
When “A” is true, “A tonk B” must be true.
Inference Rules
A tonk BB
A .
A tonk B
So what happens when “B” is false and “A” is true?
Tonk vs. the Use Theory
• The rules are supposed to be the meanings, but it seems like ‘tonk’ doesn’t mean anything, even when we know its meaning.• If the rules are just the meaning of the word, then why is it wrong to
use the word this way. And if it isn’t wrong, does that mean that Michael is the greatest philosopher!
Convention
The Disarmament Game
Country 2
Country 1
Disarm Don’t Disarm
Disarm
10
10
15
-15
Don’t Disarm
-5
5
0
0
Equilibria
An equilibrium point is a square on the grid where no player can improve his position through unilateral deviation.
Unilateral deviation is when one player changes strategy and all the other players do not.
The Disarmament Game
Country 2
Country 1
Disarm Don’t Disarm
Disarm
10
10
15
-15
Don’t Disarm
-5
5
0
0Equilibrium
Equilibria as Solutions
An equilibrium strategy is a “solution” to a game. It’s what we predict will happen, and it’s what “rational” players will choose.
John Nash proved that there’s always an equilibrium (if we allow mixed strategies).
Coordination Problem: Meeting
Suppose two people want to meet, but they have no way of communicating with each other.
It does not matter where they go, as long as they go to the same place.
The Meeting Game
Person 2
Person 1
Place 1 Place 2
Place 1
1
1
0
0
Place 2
0
0
1
1
Convention: First Definition
It is a convention for a group to follow a rule in a certain situation, if whenever they are in that situation:1. Everyone follows the rule.2. Everyone expects everyone else to follow the rule.3. The situation is a coordination problem.4. Everyone following the rule is a solution to the coordination
problem.5. The reason why they follow the rule is (3) and (4).
Example: Money
Throughout history, people have used different things as money: gold, silver, sea shells, salt (whence ‘salary’), goats, cigarettes (in prison), coins and paper currency.
It doesn’t matter to me what I accept in exchange for my goods and labor as long as it’s what everyone else accepts (as long as I can spend it).
The Currency Game
Person 2
Person 1
Accepts HKD Accepts AUD
Accepts HKD
100
100
-500
-500
Accepts AUD
-500
-500
100
100
Language and Convention
Many aspects of language are also conventional:• The meaning of each word.• Some facts about the grammar.• How the words get pronounced.
What the Word Means
Person 2
Person 1
“dog” “dog”
“dog”
1
1
0
0
“dog”
0
0
1
1
Word Order
Person 2
Person 1
SOV SVO
SOV
1
1
0
0
SVO
0
0
1
1
What Word We Use
Person 2
Person 1
“Dog” “Chien”
“Dog”
1
1
0
0
“Chien”
0
0
1
1
Compositionality
Recursion and Language
Here’s how language might do it:NOUN PHRASE:(i) “man” is a noun phrase(ii) If NP is a noun phrase then “old” + NP is a noun phrase.
From this recursive definition, it follows there are infinitely many noun phrases.
Infinite Use of Finite Means
This is one sense in which language “makes infinite use of finite means.” There are finitely many words, and the rules of grammar are presumably finite. But recursion generates infinite complex expressions from a finite “base.”
Compositionality
The meanings of complex expressions depend on– and depend only on– the meanings of their simple parts and the ways that those parts are combined.
What’s at Stake?
Before we consider arguments for or against compositionality, let’s look at what’s at stake.
At various points, compositionality has been used to argue against all of the theories of meaning we have considered in class.
Color Animal Threat LevelBrown Dog SafeBrown Ant SafeBrown Pig SafeBrown Goat SafeBrown Cow DANGER!
Red Cow SafeWhite Cow SafeBlack Cow Safe
Orange Cow Safe
Brown Cows are Dangerous
However, suppose that the small number of dangerous cows and the small number of dangerous brown things are all brown cows.
Thus the meaning of “brown cow” contains the experience of bodily harm. That experience confirms the presence of brown cows.
Brown Cows are Dangerous
But how is this possible?
Neither the set of experiences that is the meaning of “brown” nor the set of experiences that is the meaning of “cow” contains the experience of bodily harm.
Brown Cows are Dangerous
The meaning of “brown cow” thus seems to depend on something other than the meanings of its parts, “brown” and “cow”:
Verificationism violates the principle of compositionality.
Vs. the Use Theory
Does knowing how word W1 is used and how W2 is used suffice for knowing how [W1 W2] is used?
This seems unlikely.
Imagine teaching a Martian how the word ‘black’ is used.
We might show it color samples or something.
Similarly we might teach the Martian how ‘people’ is used, by giving examples.
Black Person?
Against Locality
As we saw before, compositionality is local.
In the expression [old [brown dog]] what “brown dog” means cannot depend on what “old” means, even though that’s also part of the expression containing “brown dog.”
Donkey Sentences
Normally, sentences S(‘a donkey’) are made true by the existence of a donkey who satisfies S(x). For example:
• A donkey pooped on the train.• John punched a donkey.
Geach Sentence
However, consider the following sentence (due to Peter Geach):
• Every farmer who owns a donkey beats it.
This sentence is (emphatically!) not made true by a donkey who satisfies “Every farmer who owns x beats x.”
Against Semantic Closure
Compositionality includes semantic closure: the meanings of expressions depend only on the meanings of their parts and how they’re combined, not things other than their meanings.
Pure Quotation
Pure quotation is an interesting phenomena. Consider that “bachelor” and “unmarried man” are synonymous. The substitutability criterion (compositionality) says:
“For any sentence S(E) containing some expression E as part, if E and E* have the same meaning, then S(E) and S(E*) have the same meaning.”
A Counterexample
So letE = “bachelor”E* = “unmarried man”S(E) = “‘bachelor’ used to mean squire.”S(E*) = “‘unmarried man’ used to mean squire.”
The substitutability criterion fails!
Propositional Attitudes
Common Three-Way Equivalence:
• Sentence meanings• The objects of the attitudes• The referents of ‘that’-clauses
We can call whatever is all of these things a “proposition.” Now we have the question: what are propositions?
Facts
Facts are complex entities composed of objects, properties, and relations “going together” in the world– e.g. objects instantiating properties and multiple objects instantiating relations.
Facts as Propositions?
There aren’t any “false facts.” But there are:
• Sentences that are false.• Beliefs that are false.• Attitude ascriptions that ascribe false attitudes (e.g. beleifs).
States of Affairs
States of affairs are like facts (composed of objects, properties, and relations “going together”), but they can be merely possible.
The state of affairs Michael is not wearing pants exists, even though Michael is not not wearing pants. It exists but it fails to obtain. It is merely possible.
States of Affairs as Propositions?
1. There are no impossible states of affairs, but we can believe or mean impossible things.
2. The state of affairs Superman can fly is the same state of affairs Clark Kent can fly, but I can believe that Superman can fly without believing Clark Kent can fly.
3. States of affairs are not truth-evaluable, but we might think propositions are: the things we believe are true or false.
4. Compositionality
Compositionality Worry
TRUE: Lois Lane believes Superman can fly.
FALSE: Lois Lane believe Clark Kent can fly.
What a Theory of Propositions NeedsPropositions should be:
• Fine-grained• Truth-evaluable• Sometimes necessarily false (impossible)• Compositionally determined
Possible Worlds Semantics
One way of understanding truth conditions is with possible worlds:
The meaning of a sentence S is the set of all possible worlds where that sentence is true, {w: S is true in w}.
Fine-Grainedness
One of the problems with treating states of affairs as meanings was that the state of affairs wherein Clark Kent flies is the same state of affairs wherein Superman flies.
Sets of possible worlds have the same problem: the set of worlds where Clark Kent flies is the set of worlds where Superman flies.
Thus, on this account, if you believe the one proposition, you believe the other as well.
Syntactic Structure
Michael likes Paisley
Lexicon
The lexicon is a pairing of words with their meanings.
“Michael” →
“Likes” →
“Paisley” →
Structured Proposition
Grain Too Fine?
However, the structured propositions theorist will also be forced to admit that these are different propositions:
A & B A&B
Meaning of “Superman Flies”
Meaning of “Clark Kent Flies”
Senses
MindSense of “Dog” Dog
?
Dog
grasps determines
means
Senses
For Frege, senses are objective: two people who grasp the sense of ‘horse’ are grasping one and the same thing. The sense of a word is grasped by everyone who understands it
ThinkersSense of “Dog” Dog
? grasp determines
Senses
Each object can be the referent determined by many (perhaps infinite) senses. That is, many different locutions (with different meanings) can all pick out the same thing. Some senses have no referent, e.g. ‘the least rapidly converging series’ or ‘Odysseus.’
MindSense of “Dog”
Dog
?grasps determines
?
?Sense of “Michael’s favorite animal”
Sense of “Canine”