Lecture 6 Kripke`s Naming & Necessity (.ppt)

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EINFÜHRUNG IN DIE
THEORETISCHE
PHILOSOPHIE:
SPRACHPHILOSOPHIE
Nathan Wildman
[email protected]
KRIPKE’S
NAMING &
NECESSITY
Or, an excursus into one of the most
influential philosophical texts of the previous century,
rejecting descriptivism, and a causal ‘story’ of names,
WHERE ARE WE?
o
o
o
The Naïve Theory, as we discussed it, was unable to
solve any puzzles.
Frege has a nice system which easily accounts for the
first three puzzles. However, he has trouble with (5).
Plus, his view forces us into postulating senses.
Russell’s system looks grand and has no problem with
the puzzles, but he seems to stumble when it comes to
referential uses of definite descriptions.
WHERE ARE WE?
There is a kind of unifying thesis, underlying both Frege
& Russell’s views on singular terms:
A singular term links up with its referent or has the
semantic value it does in virtue of describing it’s
referent
 Frege: the mode of presentation captured in the sense
determines the referent
 Russell: the ‘singular term’ just is a description, and
the referent is the thing that fits the description
WHERE ARE WE?
We might say that both ascribed to The Description
Theory of Names (a.k.a. descriptivism), which says that
each name N has the semantic value of some description
(be it a logical one, as for Russell, or a mode of
presentation, as for Frege).
It really is a nice theory. The only defect I think it has is
probably common to all philosophical theories. It’s
wrong. You may suspect me of proposing another theory
in its place; but I hope not, because I’m sure it’s wrong
too, if it’s a theory. [Kripke N&N p. 64.]
THE PLAN
1.
3 + 1 (Kripkean) Distinctions
2.
Descriptivism Detailed
3.
Descriptivism Destroyed
Modal objection
ii.
Semantic Objection
iii. Knowledge Objection
i.
4.
Kripke’s Positive Account
3 + 1 DISTINCTIONS
A priori versus A posteriori
Epistemic, not metaphysical or semantic

a priori: a statement is a priori iff it can be known
independently of any experience


A stronger notion Kripke rejects: a priori = can only be
known independently of experience
a posteriori: a statement is a posteriori iff it is not a
priori, i.e. if it must be known via experience
3 + 1 DISTINCTIONS
Necessary versus Contingent
Metaphysical, not epistemic or semantic

Necessary: a statement is necessary iff it couldn’t
have been false


Often discussed as truth in all possible worlds
Contingent: a statement is contingent iff it could
have been false
3 + 1 DISTINCTIONS
Analytic versus Synthetic
Semantic, not epistemic or metaphysical


Analytic: a statement is analytic iff it’s true in
virtue of its meaning
Synthetic: a statement is synthetic iff it’s not
analytic
3 + 1 DISTINCTIONS
Kant distinguished analyticity from a priority and
said that certain judgments were a priori but not
analytic:



analytic
synthetic
a posteriori
EMPTY
Everything else
a priori
logic,
definitions
physics,
philosophy,
maths
Every event has a cause
Nothing can be red all over and green all over
All triangles contain 180°
3 + 1 DISTINCTIONS
Kripke distinguishes necessity from a priority and
says that certain statements are a priori but
contingent, others necessary but a posteriori:
Necessary
Contingent
a posteriori
‘Hesperus =
Phosphorus’
‘My shirt is
black’
a priori
‘Hesperus =
Hesperus’
‘Stick S is 1
meter long’
3 + 1 DISTINCTIONS
Meaning-giving vs. Reference-fixing
Fixing the reference of a term is not always the same
as giving its meaning!
If ‘the D’ gives the meaning of ‘a’, then ‘the D’ (maybe
together with context) also fixes the reference of ‘a’,
but ‘the D’ can fix the reference of ‘a’ without giving
its meaning
E.g. reference of ‘one meter’ was originally fixed as the
length of a certain stick (‘the length of Stick S at time
t0’), but the meaning of ‘one meter’ is not the same as
‘the length of Stick S at time t0’
3 + 1 DISTINCTIONS
I.
Stick S is one meter long at t0
II. Stick S could have been slightly longer than one
meter at t0


If the meaning of ‘one meter’ is ‘the length of Stick S
at t0’, then I is analytic & necessary, and II is false
If the reference of ‘one meter’ is fixed as ‘the length
of Stick S at t0’ but the latter does not give the
meaning, then I is not analytic, and II is true
3 + 1 DISTINCTIONS
Three dimensions upon which statements can vary:



Semantic – Analytic vs. Synthetic
Epistemic – A priori vs. A posteriori
Metaphysical – Necessary vs. Contingent
Two roles descriptions can play:


Fixing reference of singular terms
Giving meaning of singular terms
THE PLAN
1.
3 + 1 (Kripkean) Distinctions
2.
Descriptivism Detailed
3.
Descriptivism Destroyed
Modal objection
ii.
Semantic Objection
iii. Knowledge Objection
i.
4.
Kripke’s Positive Account
DESCRIPTIVISM DETAILED
Basic idea
DES: the semantic content of a proper name n is the
connotation provided by a description d
associated with n

‘Aristotle’ = ‘The teacher of Alexander the Great’

‘Bucephalus’ = ‘The favorite horse of Alexander’

‘Keanu’ = ‘The sad guy on the park bench’
DESCRIPTIVISM DETAILED
‘Keanu’ means ‘The sad guy on the park bench’
Problem: Suppose that Keanu
wasn’t sad & didn’t sit on the
bench. Wouldn’t ‘Keanu’ still
refer to Keanu?
Related: Is it analytic that
Keanu sat on the bench
looking sad?
Further: Is it a priori that
Keanu sat on the bench
looking sad?
DESCRIPTIVISM DETAILED
DES:
the semantic content of a proper name n
is the connotation provided by a
description d that is associated with n
DESSD:
The semantic content of a proper name n
is the connotation provided by a single
description ‘the F’ that is associated with
n (Frege, Russell)
DESCD:
The semantic content of a proper name n
is the connotation provided by a cluster
of descriptions ‘the F, the G, and the H’
that is associated with n (Searle)
DESCRIPTIVISM DETAILED
Against DESSD: If we associate a singular description
‘the F’ with a name n, then the statement ‘n is the F’
is a necessary truth that is a priori knowable.
But ‘n is the F’ isn’t always a necessary truth that is a
priori knowable!


Bucephalus & his being Alexander’s favorite horse!
Aristotle & his being Alexander’s teacher!
Therefore, DESSD is false – there isn’t always a single
description associated with a name
DESCRIPTIVISM DETAILED
Descriptivist theory of proper names :
(1) Every name ‘n’ is associated with a cluster of
properties that x believes are true of n (DESCD)
(2) Speaker x believes that these properties pick out a
unique individual (otherwise, n wouldn’t be a
proper name!)
(3) If y has most of these properties, then y is the
referent of ‘n’ (from DESCD)
(4) If nothing has most of these properties, ‘n’ doesn’t
refer (think of Russell on definite descriptions)
DESCRIPTIVISM DETAILED
(5) The sentence ‘n has most of these properties’ is
known a priori by x
i.
‘n’ has the same semantic content as ‘The thing that
has most of these properties’
ii. Therefore, ‘n has most of these properties’ means the
same as ‘the thing that has most of these properties
has most of these properties’
iii. The statement ‘the thing that has most of these
properties has most of these properties’ is a priori!
iv. Therefore, (5)!
DESCRIPTIVISM DETAILED
(6) The sentence ‘n has most of these properties’ as
uttered by x expresses a necessary truth
i.
‘n’ has the same semantic content as ‘The thing that
has most of these properties’
ii. Therefore, ‘n has most of these properties’ means the
same as ‘the thing that has most of these properties
has most of these properties’
iii. The statement ‘the thing that has most of these
properties has most of these properties’ is necessary!
iv. Therefore, (6)!
DESCRIPTIVISM DETAILED
(C)
These properties must be chosen in such a way
that there is no circularity (i.e. no use of the
notion of reference)
CIR: For any theory of proper names T, if T tells us
that a name n is associated with a description d
that expresses a cluster of properties φ, either:
(i)
(ii)
(iii)
φ must not include the property being called n,
φ does include the property being called n but it
is possible to eliminate being called n from φ, or
T is circular
DESCRIPTIVISM DETAILED
If φ includes the property is called the name ‘n’, then
that theory would amount to telling us that a person
P has the property is called the name ‘n’ just in case S
is the referent of n
Aristotle is called ‘Aristotle’ iff he’s called ‘Aristotle’
If one was determining the referent of a name like ‘Glunk’ to
himself and made the following decision, ‘I shall use the term
‘Glunk’ to refer to the man that I call ‘Glunk’,’, this would get one
nowhere. One had better have some independent determination
of the referent of ‘Glunk’. [Kripke, N&N, p. 295]
DESCRIPTIVISM DETAILED
So, (1) – (6) are commitments of Descriptivism, (C) is
a requirement any Descriptivist account must satisfy
Note: we could re-write (1) – (6) using a non-cluster
Descriptivism; i.e. in terms of DESSD
Now that we’ve built up Descriptivism, Kripke is
going to tear it down…
THE PLAN
1.
3 + 1 (Kripkean) Distinctions
2.
Descriptivism Detailed
3.
Descriptivism Destroyed
Modal objection
ii.
Semantic Objection
iii. Knowledge Objection
i.
4.
Kripke’s Positive Account
MODAL OBJECTION TO (6)
Suppose Joe associates ‘Aristotle’ with the description
‘the teacher of Alexander the Great’. Joe says:
A
Aristotle taught Alexander the Great.
Given (6), A expresses a necessary truth.
But A isn’t a necessary truth – Aristotle could have
never gone into pedagogy
(note: this was the objection to DESSD!)
MODAL OBJECTION TO (6)
More generally: ‘it is a contingent fact that Aristotle
ever did any of the things commonly attributed to him
today, any of these great achievements that we so
much admire’ [Kripke N&N, p. 296]
i.
ii.
iii.
iv.
v.
Given (6), Aristotle necessarily satisfies our description
Possibly, Aristotle died in infancy
If so, it would follow that he didn’t do the things built into
his description (e.g. being the founder of formal logic; the
greatest student of Plato; the teacher of Alexander; …)
Therefore, Aristotle only contingently satisfies our
description
Therefore, (6) is false!
MODAL OBJECTION TO (6)
i.
If a description d gives the semantic content of a
proper name n, then the proposition expressed by
the sentence ‘if n exists, then n is d’ is necessary
ii.
There are counterfactual situations where n exists
but fails to be d
iii.
Therefore, ‘if n exists, then n is d’ is contingent
iv.
Therefore, description d fails to give the semantic
content of proper name n
AGAINST THE MODAL OBJECTION?
Serena Williams
Youngest sibling
 Tennis player
Won 4 Olympic Gold Medals
 Born in Michigan


There’s a possible world
were she’s not the youngest,
doesn’t play tennis, won no
medals, and wasn’t born in
Michigan. For example:
AGAINST THE MODAL OBJECTION?
World W1:
Middle Child
 Actress
No Olympic appearances
 Born in Indiana


But it’s still Serena!
AGAINST THE MODAL OBJECTION?
World W2:
Actor
No Olympic Appearances
 Born in Canada
 Male!


But still Serena!
AGAINST THE MODAL OBJECTION?
World W3:
Not a child at all
 Toaster!
 No Olympic Medals
Not born, manufactured


But still Serena!
AGAINST THE MODAL OBJECTION?
Potential Objection:
How do we talk about ‘Serena’ in another possible
world? Given descriptivism, wouldn’t I have to first
provide a qualitative description of the world, then
find out which (if any) of the things there is ‘Serena’?
Kripke’s Reply:
Step 1: Proper names (like ‘Serena’) are rigid
designators; (most) descriptions are non-rigid
An expression e is a rigid designator iff e refers to the
same object in all possible worlds
AGAINST THE MODAL OBJECTION?
Aside on a potential confusion:
To say that ‘Serena’ is a rigid designator is not to say
that Serena couldn’t have had a different name.
Serena could have been named ‘Monica’, and when
used by the inhabitants of the possible world where
that’s so, the name ‘Serena’ doesn’t refer to Serena.
Kripke’s Idea: when we use the name ‘Serena’, we
refer to the same individual in any possible world
where that individual exists
AGAINST THE MODAL OBJECTION?
Aside on a potential confusion:
Take world (w4) where the guy we call Nixon is
named ‘Humphrey’ & the guy we call Humphrey is
named ‘Nixon’, but where the winner & loser of the
1970 US Presidential election is the same. The
following are true about w4:
(1)
(2)
(3)
(4)
Nixon won the 1970 election – Our idiolect
Humphrey lost the 1970 election – Our idiolect
The winner of the 1970 election was named
‘Humphrey’ – Their idiolect
The loser of the 1970 election was named ‘Nixon’ –
Their idiolect
AGAINST THE MODAL OBJECTION?
Step 2: Possible Worlds aren’t discovered!
...it seems to me not to be the right way of thinking
about the possible worlds. A possible world isn't a
distant country that we are coming across, or viewing
through a telescope. Generally speaking, another
possible world is too far away. ...A possible world is
given by the descriptive conditions we associate with
it... ‘Possible worlds’ are stipulated, not discovered by
powerful telescopes. There is no reason why we cannot
stipulate that, in talking about what would have
happened to Nixon in a certain counterfactual
situation, we are talking about what would have
happened to him (N&N p. 43-4)
AGAINST THE MODAL OBJECTION?
Second Potential Objection:
Worlds like W3 above are too weird – it genuinely
isn’t possible for Serena to have been a toaster! There
are no worlds where Serena fails to be human.
Kripke’s Reply:
You must specify a description that uniquely picks out
Serena; being human isn’t going to cut it. Specify the
particular properties – I’ll bet they aren’t unique!
There might be necessary, but no sufficient
qualitative limits on how things might have been

THE PLAN
1.
3 + 1 (Kripkean) Distinctions
2.
Descriptivism Detailed
3.
Descriptivism Destroyed
Modal objection
ii. Semantic Objection
iii. Knowledge Objection
i.
4.
Kripke’s Positive Account
SEMANTIC OBJECTION TO (3)
(3)
If y has most of these properties, then y is the
referent of ‘n’ (from DESCD)
‘Kurt Gödel’
‘The man who proved the
incompleteness of arithmetic’
SEMANTIC OBJECTION TO (3)
Suppose, unbeknownst to us all, the incompleteness of
arithmetic was actually proven by Schmidt,
a friend of Gödel’s,
who’s body was found in
Vienna under mysterious
circumstances…
SEMANTIC OBJECTION TO (3)
Since the man who discovered the incompleteness of
arithmetic is in fact Schmidt, when we talk about
‘Gödel’, we’re in fact always referring to Schmidt!
‘The man who proved the
‘Kurt Gödel’
incompleteness of arithmetic’
SEMANTIC OBJECTION TO (3)
But it seems to me that we are not. [N&N, p. 298]
Gödel
Schmidt
SEMANTIC OBJECTION TO (3)
i.
From (3), if a description d gives the semantic
content of a proper name n, then the thing that
satisfies most of the d must be the referent of n
ii.
There are situations where an object a satisfies
most of d, but is not the referent of n; instead,
object b is the referent of n
iii.
Therefore, what satisfies most of d might not be
the referent of n
iv.
Therefore, (3) is false
THE PLAN
1.
3 + 1 (Kripkean) Distinctions
2.
Descriptivism Detailed
3.
Descriptivism Destroyed
Modal objection
ii.
Semantic Objection
iii. Knowledge Objection
i.
4.
Kripke’s Positive Account
KNOWLEDGE OBJECTION TO (2), (4), & (5)
(5)


The sentence ‘n has most of these properties’ is
known a priori by x
If anyone is Gödel, he (uniquely) discovered the
incompleteness of arithmetic
If anyone (uniquely) discovered the incompleteness
of arithmetic, Gödel did
Both should be truths any competent user of ‘Gödel’
should be in a position to know a priori
KNOWLEDGE OBJECTION TO (5), (4), & (2)
But even if we are competent users of the name, we’re
not in a position to know the following a priori:


If anyone is Gödel, he (uniquely) discovered the
incompleteness of arithmetic
If anyone (uniquely) discovered the incompleteness of
arithmetic, Gödel did
Suppose (again) that the discovery of the arithmetical
incompleteness is due to Schmidt, whom Gödel
murdered and stole the proof from!
This (plausible) situation flatly contradicts (5)
KNOWLEDGE OBJECTION TO (2), (4), & (5)
(4)
If nothing has most of these properties, ‘n’
doesn’t refer
It doesn’t seem to be the case – Gödel could still exist
(and ‘Gödel’ still refer), even if nobody proved the
incompleteness of arithmetic!
It seems possible that the referent of ‘n’ exists despite
the fact that there is nothing that has most of the
properties built into the description
KNOWLEDGE OBJECTION TO (2), (4), & (5)
(2)
Speaker x believes that these properties pick
out a unique individual
How much do we know about Richard Feynman?
F
‘Feynman’ means ‘The famous physicist’
Fails to distinguish Feynman uniquely from Einstein,
Gell-Mann, Hawking, etc.

The description ‘the physicist named ‘Feynman’’ would
pick him out uniquely, but it violates (C)!
KNOWLEDGE OBJECTION TO (2), (4), & (5)
Carly Rae Jepsen
The singer of ‘Call Me Maybe’
KNOWLEDGE OBJECTION TO (2), (4), & (5)
The singer of ‘Call Me Maybe’
Against (5): Did you know a priori
that CRJ sang ‘Call Me Maybe’?
Against (4): Even if nobody ever sang
‘Call Me Maybe’, ‘CRJ’
would refer to CRJ!
Against (2): Does the singer of ‘Call
Me Maybe’ uniquely pick out CRJ?
(Have you ever sung it out loud?)
THE CONSEQUENCES
Descriptivist theory of proper names :
(1) Every name ‘n’ is associated with a cluster of
properties that x believes are true of n
(2) Speaker x believes that these properties pick out a
unique individual – Epistemic Argument
(3) If y has most of these properties, then y is the
So, why accept
descriptivist
theory of proper
referent
of ‘n’ – the
Semantic
Argument
names?
(4) If nothing has most of
these properties, ‘n’ doesn’t
refer – Epistemic Argument
(5) The sentence ‘n has most of these properties’ is
known a priori by x – Epistemic Argument
(6) The sentence ‘n has most of these properties’ as
uttered by x expresses a necessary truth
– Modal Argument
THE PLAN
1.
3 + 1 (Kripkean) Distinctions
2.
Descriptivism Detailed
3.
Descriptivism Destroyed
Modal objection
ii.
Semantic Objection
iii. Knowledge Objection
i.
4.
Kripke’s Positive Account
WHERE FROM HERE?
If descriptivism is wrong, two new questions:
Reference: What determines what (if anything) a
name refers to?
 The causal theory of reference
Meaning: What is the meaning of a name?
 Names are rigid designators
CAUSAL THEORY OF REFERENCE
The referent of a name is fixed by a causal history:
It’s in virtue of our connection with other speakers in
the community, going back to the referent himself, that
we refer to a certain man
Baptism: how a name first comes to refer to a thing:
 by ostension – point at it and say ‘I name that ‘n’’
 by description – describe it (a la ‘Hesperus’)
The causal chain: after baptism, the name can be
transmitted to others via suitable causal links
CAUSAL THEORY OF REFERENCE
The causal picture of reference:
An utterance of a proper name ‘n’ refers to x iff the
utterance is at the end of a sequence of utterances of
‘n’ the first member of which is an initial baptism of
‘n’ and every other member of which is ‘properly
linked’ via a causal chain to the previous member

Example: Feynman was named by his parents, who
then transmitted his name to others, who then
transmitted it to others, who then (eventually)
transmitted it to us!
BACK TO THE BEGINNING
The necessary a posteriori
The ancients believed the Morning Star
(Phosphorous) and the Evening Star (Hesperus) were
distinct stars, though they are the planet Venus.

‘Hesperus is Phosphorous’ is a posteriori


It took empirical investigation to discover it’s truth
‘Hesperus is Phosphorous’ is necessary

The names are rigid designators, and if two names are
rigid designators and have the same referents, then they
necessarily co-refer
BACK TO THE BEGINNING
P
Perhaps the ancient Babylonians said:
It might be false that Hesperus is
Phosphorous
S is epistemically possible for y iff y’s evidence
doesn’t rule it out
 S is metaphysically possible iff S might be the case

When the Babylonians say P, they mean that for all
they know, it might be false that Hesperus is
Phosphorous – their evidence doesn’t rule it out; that
doesn’t mean it is metaphysically possible
BACK TO THE BEGINNING
The contingent a priori
Suppose we take a certain stick S and stipulatively fix
the reference of ‘meter’ by claiming that 1 meter is the
length of S at t0.


It is a priori that S is 1 meter long – ‘1 meter’ is a
rigid designator, the reference of which is fixed as
the (actual) length of S at t0!
It is contingent that S is 1 meter long – S could
have been longer or shorter than it actually is at t0!
WHAT HAVE WE LEARNED?


Distinguished our three distinctions
Offered three significant objections to the
descriptivist account of singular terms

Introduced to Kripkean notion of rigid designation

Sketched Kripkean causal theory of reference
QUESTIONS FOR NEXT TIME
1)
How can Kripke’s account handle the puzzles?
2)
Would the failure of Kripke’s account to handle the
puzzles undercut his objections to descriptivism?
Next Week:
Kripke’s A Puzzle About Belief
It’s already uploaded to the webpage. Note that the
last seven pages are footnotes – feel free to skip them

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