Kaplan’s Theory of
Indexicals
Introduction to Pragmatics
Elizabeth Coppock
HHU, Summer 2012
Indexicals
Indexical: A word whose referent is dependent on the
context of use, which provides a rule which determines
the referent in terms of certain aspects of the context.
(Kaplan 1977, Demonstratives, p. 490)
Examples: I, my, you, that, this, here, now, tomorrow,
yesterday, actual, present
Demonstratives
Demonstrative: An indexical that requires an
associated demonstration.
Examples: this, that
Cf. Fillmore’s gestural uses of deictic terms.
Pure Indexical
Pure indexical: An indexical for which no demonstration
is required.
Example: I, now, here, tomorrow.
(Although here has a demonstrative use:
“In two weeks, I will be here [pointing]”)
Two obvious principles
1. The referent of a pure indexical depends on the
context, and the referent of a demonstrative depends
on the associated demonstration.
2. Indexicals, pure and demonstrative alike, are directly
referential.
Directly referential
An expression is directly referential if its referent, once
determined, is taken as fixed for all possible
circumstances.
(Like Kripke’s rigid designators)
 Proper names (John) are directly referential
 Definite descriptions (the man) are not
Said by me today (in the US):
“The president is a Democrat”
Alternative World 2
The actual world
Alternative World 1
true
true
false
Said by me today:
“The president is a Democrat”
Alternative World 5
Alternative World 3
Alternative World 4
true
false
true
Said by me today:
“Barack Obama is a Democrat”
Alternative World 2
The actual world
Alternative World 1
true
true
true
Said by me today:
“Barack Obama is a Democrat”
Alternative World 5
Alternative World 3
Alternative World 4
true
true
true
Said by Barack Obama today:
“I am a Democrat”
Alternative World 2
The actual world
Alternative World 1
true
true
true
Said by Barack Obama today:
“I am a Democrat”
Alternative World 5
Alternative World 3
Alternative World 4
true
true
true
Conclusion
 “Barack Obama” designates the same individual in
every possible world; it is directly referential.
 “The president” can designate different individuals in
different possible worlds.
 When Barack Obama says “I”, he means “Barack
Obama”. “I” is directly referential too.
(Complication)
There are so-called descriptive uses of indexicals.
Says a prisoner on death row (Nunberg):
I am traditionally allowed a last meal.
[“I” – a person on death row.]
But nevermind that. Ignore this slide.
Recall: Directly referential
An expression is directly referential if its referent, once
determined, is taken as fixed for all possible
circumstances.
Kaplan continues:
This does not mean it could not have been used to
designate a different object; in a different context, it
might have. But regardless of the circumstance of
evaluation, it picks out the same object.
Alternative World 5
“I am a Democrat”
Actual World
Context:
Speaker=Obama: true
Context:
Speaker=Obama: true
Speaker=McCain: false
Speaker=McCain: true
Context vs. Circumstance
Context of utterance: Who is speaking to whom, where,
when, what they’re gesturing to, etc.
Circumstance of evaluation: A possible world at which
the truth of the utterance might be evaluated.
Direct Reference
 The word “I”, uttered by Barack Obama (or whoever),
picks out the same individual in every possible world /
circumstance of evaluation.
 You don’t have to look to see what properties the object
has in the possible world in order to decide what it
refers to.
 Unlike definite descriptions, whose referent depends on
who is, for example, the president.
 The only thing that can affect what “I” refers to is who
the speaker is (the context).
Fixed/Variable Meaning
 The meaning of an indexical like "I" is:
 Fixed across all circumstances of evaluation
 Variable across contexts of use
 The meaning of a definite description is:
 Variable across circumstances of evaluation
 (Arguably variable across contexts of use as well.)
Same or different meaning?
May 11, 2010:
I am turning 30
today.
May 12, 2010:
I am turning 30
today.
Same or different meaning?
May 11, 2010:
I am turning 30
today.
May 12, 2010:
I turned 30
yesterday.
Frege's answer
If somebody wants to say the same today as he
expressed yesterday using the word today, he must
replace this word with yesterday. Although the thought
is the same its verbal expression must be different so
that the sense, which would otherwise be affected by
the differing times of utterance, is readjusted.
G. Frege, in "The thought: A Logical Inquiry"
Content vs. Character
Character: The aspect of meaning that two utterances of
the same sentence share across different contexts of
utterance.
Content: The proposition expressed by an utterance, with
the referents of all of the indexicals resolved.
Same character, different content
May 11, 2010:
I am turning 30
today.
May 12, 2010:
I am turning 30
today.
Same content, different character
May 11, 2010:
I am turning 30
today.
May 12, 2010:
I turned 30
yesterday.
Strawson made a similar point about
definite descriptions
During the reign of Louis XIV
The king of
France is wise.
During the reign of Louis XV
The king of
France is wise.
Strawson: Meaning as use
Obviously in the case of this sentence, and equally
obviously in the case of many others, we cannot talk of
the sentence being true or false, but only of its being
used to make a true or false assertion, or (if this is
preferred) to express a true or false proposition. And
equally obviously we cannot talk of the sentence being
about a particular person, for the same sentence may
be used at different times to talk about quite different
particular person, but only of use of the sentence to talk
about a particular person.
Indexicals and Descriptive Content
“Indexicals have descriptive meaning, but this meaning
is relevant only to determining a referent in a context of
use and not to determining a relevant individual in a
circumstance of evaluation.”
I.e., the descriptive meaning is part of the character,
but not the content.
Imagine if it were otherwise!
Suppose “I do not exist” is true in a circumstance of
evaluation if and only if the speaker (assuming there is
one) of the circumstance does not exist in the
circumstance. Nonsense! If that were the correct
analysis, what I said could not be true. From which it
follows that:
It is impossible that I do not exist.
Impossibility
 Something that is possible is true in at least one
possible world.
 Something that is impossible is false at every possible
world.
 Something that is necessary is true at every possible
world.
Alternative World 8
The actual world
Alternative World 7
“I am here now”
 This is a logical truth, in the sense that whenever it is
uttered, it is true.
 But it is not a necessary truth, because the
circumstances could be otherwise.
Indexicals are weird!
 Normally logical truths are necessary truths!
 This is the principle of necessitation (or necessity
generalization) in modal logic.
 If p is a theorem, then ☐p is a theorem.
 theorem: a provable statement
 ☐p = "necessarily p"
 So indexicals produce "a distinctive and deviant pattern
of logical consequence" (Kaplan, The Meaning of Ouch
and Oops).
Solution
 “Indexicals have descriptive meaning, but this meaning
is relevant only to determining a referent in a context of
use and not to determining a relevant individual in a
circumstance of evaluation.”
 In other words, the descriptive content of an indexical
goes into determining the character, but not the
content.
What is a content?
 The content of a sentence is a proposition.
 A proposition is a set of possible worlds, or a mapping
from possible worlds to truth values.
 e.g. {w1, w3, w4}
 Another way of saying it: a proposition determines the
circumstances in which the sentence is true.
 circumstances (of evaluation) = possible worlds.
 Another way to think about propositions: Functions
from circumstances to truth values.
 e.g. f(w1) = 1, f(w2) = 0, f(w3) = 1, f(w4) = 1, etc.
Intension vs. Extension
 The actual truth value of a sentence in a particular
world is its extension.
 The proposition that a sentence denotes can be
thought of as a function from circumstances of
evalution to extensions.
 Such a function is an intension (Carnap).
 Nouns like dog also have intensions and extensions.
 Intension + Possible World => Extension
 Content + Circumstance => Extension
What is a character?
 The character of a sentence is something that, given a
context of utterance, gives you a content.
 Formally: A function from contexts to contents
The Kaplanian Picture
 Character + Context => Content
 Content + Circumstance => Extension
{
Character + Context + Circumstance => Extension
Content
Strawson: Meaning as use
Meaning (in at least one important sense) is a function
of the sentence or expression; mentioning and referring
and truth or falsity, are functions of the use of the
sentence or expression. To give the meaning of an
expression (in the sense in which I am using the word)
is to give general directions for its use to refer to or
mention particular objects or persons; to give the
meaning of a sentence is to give general directions for
its use in making true or false assertions.
Strawson (1950), On Referring
Kaplan's Reflections on
Demonstratives
In [Demonstratives], I tried to show that by adding
context as a parameter, Strawson's "conventions for
referring" as he calls them, even if neglected by
logicians, could be accommodated within the range of
our methods. And at the time I regarded my work as
extending current semantical methods just to the
degree necessary to incorporate the indexicals. I
regarded what I was doing as a sort of epicycle on
Carnap's method of extension and intension and I
didn't think of it as involving any different conception of
semantics or what semantics was supposed to do.
Kaplan's Reflections on
Demonstratives, cont'd
Some years ago, it occurred to me that the analysis of
indexicals in Demonstratives could be seen as the
scientific realization of a Strawsonian semantics of use.
Ask not after other-worldly meanings, ask only after
rules of use.
--David Kaplan, The Meaning of Ouch and Oops