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Saying the Same Thing
Concepts • Counting by
– Sentence token
– Sentence type
– Proposition
– Statement
• Synonomy
• Ambiguity• Context Dependence
• Sense
• Reference
• Indexical
What we’re doing here
• Arguing that there are necessary truths
• Explaining how sentences have meaning in virtue of the “families” to which they belong
• Noting that the meaning of a sentence depends on the language in which it figures and, sometimes, its context of utterance.
Different Ways of Counting
8 individual objects
Different Ways of Counting
3 colors
Different Ways of Counting
2 shapes
Are they the same?
Same shape,Different color
Different shape,Same color
The Moral: we can count things in different ways, and come up with different correct answers when counting the same objects.
There are 4 individual objects, 3 colors and 2 shapes represented in this picture.
Count the letters . . .
BANANA
Counting by TYPE
BBAANNAANNAA
There are 3 letters of the alphabet in “banana”
Counting by TOKEN
BBAANNAANNAA
There are 6 individual letters in “banana”
Type/Token Ambiguity
• “My husband and I drive the same car.”
• “Tweedledee and Tweedledum are identical twins.”
2 sentence tokens - 1 sentence type
1. John is Paul’s brother
2. John is Paul’s brother
1. John is Paul’s brother
2. John is Paul’s brother
TYPE and TOKEN aren’t different kinds of things like apples and oranges--they’re just two different ways of counting the same things.
We can count sentences by token or by type.
1 proposition
1. John is Paul’s brother
2. John is Paul’s brother
3. John is the male sibling of Paul
1. John is Paul’s brother
2. John is Paul’s brother
3. John is the male sibling of Paul
1, 2 and 3 express the same proposition because they have they have the same sense, i.e. dictionary-meaning. They are synonymous.
Counting by PROPOSITION is another way of counting sentences
What are propositions really???
• Equivalence class
– example: denominations of bills
• We can group things in different ways
• Equivalence relation
– reflexive
– symmetric
– transitive
Equivalence Class
• 14 bills – 4 denominations
• More about equivalence classes here
Synonomy
You should eschew obfuscation.
You should avoid obscurity.
Snow is white.
Owsnay isay itewhay.
Sentences are synonymous
when they express the same
proposition.
tomato
tomAHto
Ambiguity
I’m high!
Flying planes can be dangerous.
A sentence is ambiguous when it can be
used to express different propositions.
Context Dependence
A sentence is context dependent when what it says depends upon the context of utterance, that is where, when, by whom and in what circumstances it is said.
Examples of context dependent sentences
• I am a philosopher
• Los Angeles is to the north of here
• It’s 10 am now.
• This dang thing is heavy!
I’m aphilosopher
I’m aphilosopherI’m a
philosopherI’m a
philosopher
Plato is a philosopher
Aristotle is a philosopher
Plato and Aristotle saying that they’re philosophers
Indexicals
• Words whose reference changes systematically depending on where, when, by whom and in what circumstances they are uttered.
• Examples: I, you, he, today, yesterday, tomorrow, here, there, this, that, now…
Sense/ReferenceDistinction
• “meaning” is ambiguous!
– “bachelor” means “unmarried male who never has been married.
– I mean him!
• Frege “Auf Sinn und Bedeuting”
• Sense: dictionary-meaning
• Reference: “aboutness”, picking out
Sense and Reference
squaresquare
square
sense
reference
Same Statement
• Sentences make the same statement when they say the same thing about the same thing.
• Example
1. 50 is even.
2. The number of states in the US is even.
• 1 is always true but2 was not true in 1812!
• Sentences make the same statement when they say the same thing about the same thing.
• Example
1. 50 is even.
2. The number of states in the US is even.
• 1 is always true but2 was not true in 1812!
1812 Flag1812 Flag
Example: A Question from an Old Quiz
It’s my shoe.
It’s my shoe.
It’s my shoe.It’s my shoe.
It’s your shoe.
It’s your shoe.
Which sentences say the same thing?
1. [stated Sep 12, 2013] Today is Thursday.
2. [stated Sep 13, 2013] Today is Thursday.
3. [stated Sep 13, 2013] Yesterday was Thursday.
1. [stated Sep 12, 2013] Today is Thursday.
2. [stated Sep 13, 2013] Today is Thursday.
3. [stated Sep 13, 2013] Yesterday was Thursday.
It depends on how you count!
Same proposition/different statements
1. [stated Sep 12, 2013] Today is Thursday.
2. [stated Sep 13, 2013] Today is Thursday.
3. [stated Sep 13, 2013] Yesterday was Thursday.
1. [stated Sep 12, 2013] Today is Thursday.
2. [stated Sep 13, 2013] Today is Thursday.
3. [stated Sep 13, 2013] Yesterday was Thursday.
1 and 2 have the same sense--same dictionary-meaning
Same statement/different propositions
1. [stated Sep 12, 2013] Today is Thursday.
2. [stated Sep 13, 2013] Today is Thursday.
3. [stated Sep 13, 2013] Yesterday was Thursday.
1. [stated Sep 12, 2013] Today is Thursday.
2. [stated Sep 13, 2013] Today is Thursday.
3. [stated Sep 13, 2013] Yesterday was Thursday.
1 and 3 don’t have the same dictionary-meaning but they pick out the same day.
They say the same thing about the same thing.
Translating into timeless sentences
1. [stated Sep 12, 2013] Today is Thursday.
2. [stated Sep 13, 2013] Today is Thursday.
3. [stated Sep 13, 2013] Yesterday was Thursday.
1. [stated Sep 12, 2013] Today is Thursday.
2. [stated Sep 13, 2013] Today is Thursday.
3. [stated Sep 13, 2013] Yesterday was Thursday.
1’ Sep 12, 2013 is a Thursday.
2’ Sep 13, 2013 is a Thursday.
1’ Sep 12, 2013 is a Thursday.
2’ Sep 13, 2013 is a Thursday.
1. [stated Sep 12, 2013] Today is Thursday.
2. [stated Sep 13, 2013] Today is Thursday.
3. [stated Sep 13, 2013] Yesterday was Thursday.
1’ Sep 12, 2013 is a Thursday.
2’ Sep 13, 2013 is a Thursday.
context-dependent
not context-dependent
We can translate context-dependent sentences into sentences that are not context-dependent
Remember her?
Summing up so far…• We distinguished different ways of counting sentences
– by sentence token
– by sentence type
– by proposition
– by statement
• We noted that some sentences were context-dependent because they included indexicals but
• that they could be translated into context-independent sentences.
When we ask whether two sentences (or speakers) are “saying the same thing” we need to be clear about what we’re asking.
• Expressing the same proposition?
• Making the same statement?
• Uttering the same noises (or making the same marks)?
The Moral of the Story
A Puzzle About Necessary Truths
How We Argue in Philosophy
• When we want to argue for a thesis we need to respond to objections
• So sometimes we consider an argument for something we want to show is false
• In order to refute it
• We will consider a bad argument that is supposed to show there are no necessary truths
• And refute it
Bad argument(supposed to show there are no necessary truths)
2 + 2 = 4 - true
2 + 2 = 5 - false
English
4 = ****
5 = *****
Actual World
2 + 2 = 4 - false
2 + 2 = 5 - true
English*
4 = *****
5 = ****
W*
This argument can be generalized!
• It is contingent that any given word has the sense it does: we can change language!
• So it seems there can be no necessary truths!
• But this is crazy: changing language doesn’t change the world! So we have to respond to this threat!
2 + 2 = 42 + 2 = 42 + 2 = 52 + 2 = 5
** + ** = ****** + ** = ****
** + ** = ****** + ** = ****
English-Speaker English*-Speaker
They’re making the different noises…
but expressing the same mathematical truth!
2 + 2 = 42 + 2 = 42 + 2 = 42 + 2 = 4
** + ** = ******* + ** = *****
** + ** = ****** + ** = ****
English-Speaker English*-Speaker
Now they’re making the same noises…
but expressing the different mathematical propositions!
Changing language doesn’t change the world!
2 + 2 = 4 - true
2 + 2 = 5 - false
English
4 = ****
5 = *****
Actual World
2 + 2 = 4 - false
2 + 2 = 5 - true
English*
4 = *****
5 = ****
W*
** + ** = ****** + ** = *****
True
False
Lincoln’s Riddle
If you call a tail a leg, then how many legs does a dog have?
Changing language doesn’t change the world!
Four.Calling a tail aleg doesn’t makeit one.
Four.Calling a tail aleg doesn’t makeit one.
The EndThe End