Tutorial #10. Kripke on Names. Discussion Questions

After having read the relevant parts of Naming and Necessity think about these questions.

• What is the difference between a priori-a posteriori and necessary-contingent?
• Kripke argues that some a priori propositions are contingent. Do you find his argument convincing?
• What is Kripke’s argument against Frege and Russell? Why does he think that names do not have some form of descriptive meaning?
• What reasons does Kripke have for claiming that names are rigid designators?
• How does it happen that 'Pegasus' is a non-referring name at our world?
• How are contingent identity statements possible?
• Are mental states identical to brain states for Kripke?
• What’s essential to pain? Could pain be painless?

Tutorial #10. Kripke on Names. Some Consequences

---> Essentialism
+ Essential property: a property an object (or kind) cannot fail to have.
- Example: being a football player is not essential to Ronaldo but being human is essential to him.
- Example: Water is H2O. There could be a colorless, tasteless liquid that was just like water, and also called 'water' by people, but with molecular structure XYZ. Then, that liquid would NOT be water: The essence of water is it’s molecular structure (H2O).

+ What about what seem to be contingent identity statements involving rigid designators?
E.g.
- 'Hesperus is Phosphoros.'
- 'Heat is the total energy of molecular motion.'

Kripke: The alleged contingency of both these sentences is an illusion!
They are a posteriori but necessary. The illusion comes from confusing necessity and a prioriticity!

--> How are contingent identity statements possible?
Everything that exists is necessarily self-identical.
Referring expressions in some identity statements pick out different objects at different possible worlds.

Tutorial #10. Kripke on Names. Rigid Designators

Rigid Designator
A rigid designator designates (picks out, denotes, refers to) the same thing in all possible worlds in which that thing exists and does not designate anything else in those possible worlds in which that thing does not exist.

--> Kripke: Ordinary proper names are rigid designators!

NOTE
In saying that 'Saul Kripke' is a rigid designator we mean that the name as we use it in our actual world language refers to the same individual at all possible worlds--including worlds in which he has a different name.
Kripke couldn’t be Ronaldo even though he could have been named 'Ronaldo.'

Kripke vs. Russell
- Ordinary proper names are NOT disguised descriptions for Kripke.
- Ordinary proper names are mere tags (they don’t have senses or convey descriptions).
- We confer names on objects by tagging (baptizing, dubbing) or via descriptions that fix reference.

--> Names are passed down in the linguistic community through a causal chain going back to the tagging (the "baptism").

Tutorial #10. Kripke on Names. Nuts and Bolts

Bits of Terminology

Possible Worlds: Ways things could have been.
The actual world: the way things actually are.
Possible worlds, in philosophy, are used to explain modal notions like logical possibility, necessity and contingency.

--> Necessary & Contingent
- A state of affairs is logically possible if it’s true at some possible world.
- A proposition is necessarily true if it’s true at all possible worlds.
- A proposition is contingently true if it’s true at the actual world (or the world we’re considering) but false at some other possible world.


--> A priori & A posteriori
- A priori: knowable "before" experience. E.g. "All bachelors are unmarried."
- A posteriori: can only be known "after" experience. E.g. "Miriam is 10 ft. tall"

NOTE
A priority and a posteriority are epistemic notions.
Necessity and contingency are metaphysical notions.


+ Kripke On A Priori\A Posteriori & Necessity\Contingency:

Some a priori propositions are contingent!
Example: The standard meter rod in Paris is one meter long.

Some a posteriori propositions are necessary!
Example: Water is H2O.

Tutorial # 9. Russell. On Denoting. Discussion Questions

After having read Russell's On Denoting, try to think about the following questions.

• What is a definitive description? Give examples.
• What is the logical form of a sentence? Why is it important?
• How would Russell analyze the sentence “Catwoman is hot”?
• Is ordinary language “good enough for philosophy”, or does it require modifications? Why?
• How can we talk about things which do not exist? Think about Meinong’s, Frege’s and Russell’s answers to this question. Which is the most convincing? Why?
  
• What is Russell’s criticism to Frege’s theory of meaning?
  
• How does Russell treat propositional attitudes? How would he analyse the sentence "Matteo believes that the present queen of Italy is hot"?
  
• What is the difference between knowledge by acquaintance and knowledge by description? Give examples. Why is it related to Russell’s analysis of definitive descriptions?

Tutorial # 9. Russell. On Denoting. Denoting in "On Denoting"

The subject of denoting is of very great importance, not only in logic and mathematics, but also in the theory of knowledge.

- No general characterization of denoting is given, only a list of “denoting phrases.”

A man,
Some man,
Any man,
Every man,
All men,
The present King of England.

"A phrase is denoting solely in virtue of its form"

+ The notion of a variable is fundamental to the theory of denoting.

A variable x "is essentially and wholly undetermined."

A proposition is always of the form C(x)

A proposition results from replacing the variable with a denoting phrase, as with C(a man).

Russell’s general thesis is that propositions containing denoting phrases are reducible to propositions not containing them.

*The Reduction

C(a man) means C(x) and x is human for some values of x.

"I met a man." means "I met x, and x is human for some values of x."
"All men are mortal” means “If x is a man, then x is mortal for all values of x"

--> “a man” and “all men” are contextually defined:
they have meaning only when embedded in a larger context.

*Definite Descriptions
Denoting phrases preceded by "the" are "by far the most interesting and difficult of denoting phrases."
Like the other denoting phrases, definite descriptions are contextually defined.

- Strict use of a denoting phrase in the sentence “The father of Charles II was executed” involves:

Existence: x was father of Charles II, for some value of x.

Uniqueness: if y was father of Charles II then y is identical with x, for any values of x who was father of Charles II and any value of y.

The Reduction of Definite Descriptions
The definite description "the father of Charles II" may occur in propositions of the form C(the father of Charles II).

The general analysis of C(the father of Charles II) combines existence and uniqueness:

For some value of x, x was father of Charles II, and C(x), and if y was father of Charles II, then y is identical to x, for any value of y

"The father of Charles II was executed” is:
For some value of x, x was father of Charles II, and x was executed, and if y was father of Charles II, then y is identical to x, for any value of y.


*** Consequences for Knowledge


Acquaintance and Description
The theory of denoting has consequences for knowledge.
We know things in two ways:

I) By being acquainted with them,
II) Through descriptions of them.
If we can apprehend (think about) a proposition, then we are acquainted with all its constituents.
If we know an object (say, someone else’s mind) only by description, then our knowledge can be expressed in propositions with denoting phrases, which do not contain the object itself.
We then know only the properties of the object and do not know any propositions
which contain the object itself.

Tutorial # 9. Russell. On Denoting. The Problem

The Puzzles.

"How can I think the thing which is not?"
(Plato)

* A denoting phrase may or may not denote an actual object.
In 1905
"The present King of England" denoted a certain man.
"The present King of France" denoted nothing at all.
Pegasus is a winged horse
Unicorns don’t exist

What, if anything, am I talking about when I talk about Zeus, unicorns, the Fountain of Youth, etc?

If I’m not talking about anything, how can my talk be meaningful?
If I’m not talking about anything, how can my talk be true or false?


*A second problem
Some denoting phrases denote ambiguously.

In “I saw a man,” “a man” denotes an “ambiguous” (or undetermined) man.

A good theory of denoting will accommodate all these kinds of cases.

Russell's Solution!
Analyze ordinary talk to reveal its true logical form beneath the surface
--> Denoting expressions are not names
A proper analysis of sentences in which denoting expressions occur solves our problems!