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Causal Theories
THE ABSURDITY OF FIT
The Absurdity of Fit
In one sense, all the views we’ve considered in
class so far are views on which meaning is a type
of “fit.” On the idea theory, meanings
(connotations) are ideas. Ideas have a certain
pre-existing structure: just as in a painting the
different parts are related to one another, and
colored in various ways, and so forth.
Idea Theory and Fit
In order to find out what an idea represents, we
go out and find the things that best fit the idea,
that most closely match its pre-existing
structure, that best resemble it. Whatever best
fits the pre-existing structure is what the idea
represents.
Verificationism and Fit
While verificationism doesn’t have the same
“little colored pictures” view of ideas or the
resemblance theory of representation, it too
involves a type of fit. In advance, words are
associated with specific experiences that are
stipulated to verify them. Why does a certain
experience verify “That is red”? Because we said
so, that’s why. We say in advance what
experiences verify which sentences, then we go
look and see what experiences we have.
Definitions and Fit
Similarly, a definitions view is a type of fit as
well. We say in advance what the definitions of
words are. You don’t discover that bachelors are
unmarried, you sit down and make it true by
fiat.
The Absurdity of Fit
But there’s something terribly wrong with the
idea that meanings are specified in advance of
our encounters with the world. That before any
experience of the world, we sit down and draw
up a structural description, or a set of
experiences, or a verbal description and say
“whatever I find that’s like this, I will call ‘a
dog’!”
The Paradox of Inquiry
The worry here is that on any of these models,
you can’t be radically wrong. If ‘gold’ is true of
what most closely resembles your idea of gold,
then most of your beliefs about gold must be
true. And the same goes for most of your beliefs
about anything. If representation is what fits
best with what you’ve drawn up in advance, in
advance of inquiry, you can be pretty sure you
already know what’s true and what isn’t.
The Paradox of Inquiry
In fact, this problem is as old as Plato, and it’s
called “the paradox of inquiry.” The paradox is:
suppose you want to know, say, the nature of
lightning. If you know what lightning is in
advance, then you don’t need to investigate,
because that’s what you wanted to know. But if
you don’t know, how do you know when you
discover it, that lightning is X? You find X, but
you don’t know that it’s lightning, because you
don’t know what lightning is!
Causal Theories
Causal theories of meaning are radically
different from the “fit” views we’ve been
considering. They say (roughly) that a word or a
concept represents what causes you to say it or
think it. So even if all your beliefs about gold,
and all your utterances concerning gold are
completely false, those thoughts/ sentences still
represent gold so long as gold is responsible for
you believing/ saying them.
CAUSATION IN PHILOSOPHY
A classic problem in philosophy since before
Socrates is: “What is knowledge?” What’s the
difference between believing something and
knowing it?
A little reflection tells us that if you know
something, then it has to be true. So maybe
knowledge = true belief.
Socrates/ Plato vs. K = TB
Suppose there has been a murder, and no eyewitnesses
Suppose the jury is superstitious, and I convince
them that X is guilty, b/c I dreamed that he was.
No one is inclined to say that the jury knows
that X is the killer.
But if I was accidentally right, they will have a
true belief that X is the killer.
True Beliefs, Bad Reasons
Here the important point is that a belief that is
true, but which you believe for bad reasons, is
not really knowledge.
If you believe something because you want to,
or because your horoscope says it, or because a
really unreliable person told it to you, then you
don’t know it.
K = JTB
This naturally suggests that for a belief to be
knowledge, it not only has to be true, but has to
be held for a good reason. This is the classic
“JTB” account: knowledge = justified true belief.
The reason the jury doesn’t know X is the killer
is that Michael dreaming that X is guilty doesn’t
justify anyone in believing that X is guilty (even if
it’s true that they are guilty).
Gettier Cases
However, in the hyper-classic 1963 paper “Is
Knowledge Justified True Belief?” Edmund
Gettier provides reasons for thinking K ≠ JTB.
Here’s an example of a “Gettier case.”
Justification
I’m at your house and I notice an iphone 5, a
receipt for the purchase of an iphone 5 with
your name on it, and a letter to your
grandmother in your handwriting with the
words “Dear Grandma, I just got an iphone 5”
on it. I conclude justifiedly that you own an
iphone 5.
Props
However, suppose that the phone, the receipt,
and the letter were just props for a movie you
were making. (The next scene in the movie
involves all of the props being smashed, and you
wanted to convey how disappointed the
character [who happens to have your same
name] would be.) However, you really do own
an iphone 5: it’s in your pocket where I can’t see
it.
The Causal Account of Knowledge
In this case I have a JTB that you have an iphone 5,
but intuitively I don’t know that you do.
What’s going on here? Well, some philosophers
(e.g. Dretske 1981) think that this shows knowledge
isn’t justified true belief, it’s true belief that’s
caused by the fact the belief is about. My belief that
you have an iphone 5 is not caused by your iphone
5, it’s caused by a prop. So I don’t know.
Right Direction
The causal account has its problems (can’t we
know things about the future even though
causation doesn’t go from future to past?), but
to many it seemed like the right direction. To
know something is to have your beliefs based on
the facts, where “based on” is some sort of
causal notion.
The Success of Causal Theories
• Knowledge (Dretske): X knows proposition P =
the information that P causes X to believe P.
• Action (Goldman): X performs action A = X’s
beliefs and desires cause A.
• Perception (Grice): X perceives object O = O
causes an experience in X.
• Representation?
CAUSATION AND REPRESENTATION
Motivations
But why think that causation has anything to do
with representation?
Greater Determinacy
Imagine you’re in a mirror universe (or an
eternal recurrence universe). You look at a table,
and have a thought about it. You say “that’s a
nice table.” Someone just like you in the other
half of the “mirror” is having exactly similar
experiences and saying exactly the same words.
Why are your thoughts and your words about
the table in front of you? Proposal: because that
table is the one that caused your thoughts and
your words, not the other table.
Fit is Inappropriate
My experience of red represents a certain
reflectance property of surfaces (reflects
wavelengths between 630 and 700nm). But my
experience in no way resembles that reflectance
property any more than it resembles the
reflectance property blue surfaces have (450 to
495nm). So why does my experience of redness
represent the reflectance property it does?
Because that’s the property that causes the
experience.
Causation has the Right Structure?
Representation
Non-reflexive
Asymmetric
Intransitive
Resemblance
Reflexive
Symmetric
Transitive
Causation
Irreflexive
Antisymmetric
Transitive
Structure
Notice importantly that cases that show
representation is non-reflexive rather than
irreflexive, and asymmetric rather than
antisymmetric include the semantic paradoxes:
1. This sentence is false.
2. Sentence #3 is false.
3. Sentence #2 is true.
Possibility of Radical Error
One of the most promising aspects of a causal
theory of meaning is that it can allow for the
possibility of radical error. If “atom” means
whatever it is that causes me to use the word
“atom,” then it’s possible that all my beliefs
about atoms (that they have determinate
locations and momenta, they’re point-like, they
behave only like particles, etc.) might be false
and yet “atom” still means atom.
Coordination across Theories
A related upshot is that two people with
radically different theories can nevertheless be
talking about the same thing, and hence be
meaningfully disagreeing with one another. I
might think “abortion is the morally wrong thing
that kills babies” and you might think “abortion
is the morally acceptable thing that destroys a
handful of cells.”
Coordination across Theories
We can’t be talking about the same thing on a
“fit” view. Nothing is both morally right and
morally wrong. However, on a causal view, since
abortions both cause me to apply the word
“abortion” and cause you to do so, we’re talking
about the same thing, and meaningfully
disagreeing about it. It’s just that one of us is
radically wrong.
THE CAUSAL-HISTORICAL ACCOUNT
Background
Kripke’s causal-historical account is developed in
his groundbreaking Naming and Necessity. The
background is that he’s arguing against views on
which the meanings of names (hence the first
half of the title) are descriptions or definitions.
This was a popular empiricist/ Russellian/ logical
positivist view: the meaning of ‘Michael’ for
example was constructed from basic sensations/
universals/ protocol sentences.
Against Descriptivism
Kripke argues that for any name N, there is no
description D that we associate with N such
that:
1. If x satisfies the description, N = x.
2. If N = x, then x must satisfy the description.
Ignorance & Error
He argues against each claim as follows:
Against #1: Arguments from ignorance.
Sometimes lots of things satisfy the descriptions
we associate with N, but only one is N.
Against #2: Arguments from Error. Sometimes
nothing satisfies the descriptions we associate
with N (or some non-x does), but N still = x.
Ignorance: Feynman
Kripke’s first argument is this. Lots of people
sensibly talk about Richard Feynman. If asked
“What is everything you know about Feynman?”
they might reply “He’s a physicist, he’s famous,
he’s dead, and he worked on quantum
mechanics.” Lots of people satisfy that
description (Bohr, for example). But it’s not true
that ‘Feynman’ means Bohr and it’s not true
that it means nothing. How is that possible for
the descriptivist?
Error: Einstein
Kripke’s second argument goes like this. Lots of
people (this is back in 1970 when Kripke was
writing) know almost nothing about Einstein. If
asked “What is everything you know?” they
might respond, “Einstein invented the nuclear
bomb.” But “the inventor of the nuclear bomb”
can’t be the meaning of ‘Einstein’ because then
‘Einstein’ would refer to Leo Szilard (or
whoever).
Kripke’s Picture
“Someone, let’s say, a baby, is born; his parents call
him by a certain name. They talk about him to their
friends, Other people meet him. Through various
sorts of talk the name is spread from link to link as
if by a chain. A speaker who is on the far end of this
chain, who has heard about, say Richard Feynman,
in the market place or elsewhere, may be referring
to Richard Feynman even though he can’t
remember from whom he first heard of Feynman or
from whom he ever heard of Feynman.”
Kripke’s Picture
“A rough statement of a theory might be the
following: An initial ‘baptism’ takes place. Here
the object may be named by ostension, or the
reference of the name may be fixed by a
description. When the name is ‘passed from link
to link’, the receiver of the name must, I think,
intend when he learns it to use it with the same
reference as the man from whom he heard it.”
Reference-Fixing Descriptions
So Kripke’s idea is that descriptions may be used
to initially latch on to or think about an
individual (“this baby in front of me…”).
However, what gives a name its meaning now is
not any description or definition whatsoever.
The name inherits its meaning from the people
you got the name from. This means that
everything you believe about Einstein could be
false, and you can still think of Einstein.
Natural Kinds
Kripke and another philosopher Hilary Putnam
wanted to generalize what was true of names to
“natural kind terms” (a phrase introduced by
Quine). There’s no real consensus on what this
class encompasses, but common examples
include: fundamental particles (electrons),
chemical substances (cesium), biological taxa
(chimpanzees), natural phenomena (lightning),
secondary qualities (heat).
Ignorance: Water
In Hilary Putnam’s classic “The Meaning of
‘Meaning’” he argues that “meaning just ain’t in
the head.” In particular, he presents his famous
Twin Earth thought experiment, which is
intended to show that what the word ‘water’ is
true of is not determined by what we know or
believe about water.
Twin Earth
Twin Earth is a planet on the other side of the
galaxy. In most ways, it is just like Earth, down to
the smallest detail. You have a twin on Twin
Earth who’s just like you, I have a twin who’s just
like me, they’re sitting in a twin classroom, and
my twin is giving a lecture just like this one to
your twin. And so on and so forth.
Earth
Twin Earth
Twin Earth
There is however one difference between Earth
and Twin Earth. On Earth, all the watery stuff is
H2O. On Twin Earth, the watery stuff is
composed of a complicated chemical compound
we can abbreviate XYZ.
H2O and XYZ look and behave exactly the same.
They taste the same, they boil at the same
temperatures at the same distance above sea
level, their conductance is the same, etc.
Twin Earth
Consider two twins,
Arnold on Earth and Twin
Arnold on Twin Earth.
Neither knows any
chemistry. What they
know/ believe about the
stuff they call ‘water’ is
the same. Q: Would it be
true for Arnold to call the
stuff on Twin Earth
‘water’?
Twin Earth
The intuition is supposed
to be that, no, Arnold’s
word ‘water’ is true of all
an only H2O, whereas
Twin Arnold’s word
‘water’ is true of all and
only XYZ
The Moral
The conclusion Kripke and Putnam draw from
such cases is that we fix the referent of ‘water’
by a description like “the stuff around here in
lakes and rivers and streams that falls from the
sky and quenches thirst.” But this description
only fixes the referent. If you replaced all the
H2O on Earth with XYZ, there wouldn’t be any
more water here.
Error: Gold
Neither Kripke nor Putnam present any real
cases where, through error, our beliefs about X
are completely false of X, yet “X” still means X
(like the Einstein case). (There’s probably lots of
cases in contemporary physics.) But Kripke
presents some imagined ones. Kant thought that
the definition of gold was ‘yellow metal.’ Kripke
then asks, “Could we discover that gold was not
in fact yellow?” p. 118.
Imagine Gold’s Not Yellow
Kripke argues that we could. He asks us to
suppose that something is weird about the air in
places where gold is most prevalent. This
strange air makes it appear that gold is yellow,
but when we isolate gold in normal air, it’s
obviously blue. Since this is clearly conceivable,
it can’t be that gold means yellow metal,
because if X means Y, then anything that is X is Y.
Error: Tigers
Here’s a case from Paul Ziff in Semantic Analysis
(referenced in Kripke p. 119 of 1980 edition).
The Shorter OED has “the tiger is a large
quadrupedal feline, tawny yellow in color, with
blackish transverse stripes and a white belly.”
Ziff argues that this can’t be what ‘tiger’ means,
because if someone said “I just saw a threelegged tiger,” that wouldn’t be a contradiction.
Kripke goes on to argue that we could discover
that something with none of the characteristics
in the definition might still be a tiger. All
previous zoologists who handled tigers were
incompetent: they’re really lizards, they just look
like felines. Their skin isn’t orange, because of
optical illusions familiar from the gold case. Etc.
The point is not that this is very likely. It’s that
it’s conceivable, and it shouldn’t be (if
definitions are meanings).
The Moral
The moral of the story is that often our
reference-fixing goes on in the absence of any
true descriptions. Tigers are “those things over
there, the dangerous ones that you don’t want
to stand by.” We later discover that those things
are felines, and have four legs, etc. But that’s
not known in advance, as part of the meaning of
‘tiger.’ ‘Tiger’ applies to those things we initially
baptized ‘tigers’ whatever they are.
The Epistemic Argument
Kripke had two other arguments against
description theories (which he took to support
his own account). First, suppose someone says
“Aristotle means the last great philosopher of
antiquity.” It is true that if x is named ‘Aristotle’
then x was the last great philosopher of
antiquity and vice versa. So this is not a
Feynman or an Einstein case.
The Epistemic Argument
However, it still seems as though you don’t have
the same sort of epistemic access to this fact as
to other clearer cases of definition like
‘bachelors are unmarried men.’ You don’t know
for sure that Aristotle was the last great
philosopher of antiquity. It could turn out false.
It could turn out that Aristotle was just a
medieval forgery. If it were a definition, you
should know for sure. But you don’t.
The Modal Argument
Finally, Kripke argues that the modal properties
of names are different from those of definitions:
FALSE: If things had gone differently, Aristotle
might not have been Aristotle.
TRUE: If things had gone differently, Aristotle
might not have been the last great philosopher
of antiquity.
CHALLENGES
Huge Literature
There’s been an enormous literature on Kripke
and Putnam (and I should mention Donnellan). I
can’t explain all of the objections, but I’ll
mention a few classic ones, and a recent
challenge from Machery, Mallon, Nichols &
Stich.
Madagascar
Evans points out that the word ‘Madagascar’
once referred to a portion of the African
mainland. Through confusion, Europeans
thought that it applied to an island to the west
of the mainland. Now, ‘Madagascar’ applies to
the island but no one in the chain of
transmission ever intended to change the
referent.
Twins Switched at Birth
He also gives a case of twins switched at birth.
Suppose baby X is named “Xena” and baby Y is
named “Yoyo.” An hour after they’re named
(“baptized”), a careless orderly switches their
name tags. For the rest of their lives, X is called
“Yoyo” and Y is called “Xena.” Evans finds it
intuitive that when X fails math and Y passes, we
can truly say “Yoyo failed and Xena passed.”
Jade
Another troublesome example for the causal
theory involves terms like ‘jade.’ There are two
distinct minerals called ‘jade’: jadeite and
nephrite (not discovered till 19th C). Let’s
suppose that when ‘jade’ was introduced,
someone said “Let ‘jade’ apply to the mineral
around here that…” But there’s no one mineral
that was picked out in the baptism. Normally
that wouldn’t mean both count. But in this case!
Machery, Mallon, Nichols & Stich
In their highly influential 2004 paper
“Semantics, Cross-Cultural Style,” MMNS claim
to uncover evidence that while Westerners have
intuitions that accord with Kripke and Putnam
(that is for causal-historical theories and against
descriptivism), East Asians have (on average)
more descriptivist intuitions. For example, they
think in the Twin Earth case, XYZ is water.
According to MMNS!
MMNS
I am personally weary of the methodology, and I
find it a little bit silly to think that anyone, East
Asian or not, thinks that Americans who only
believe about Neil Armstrong that he was the
first man in space, speak truly when they say
“Neil Armstrong was the first man in space.”
[Descriptivist says TRUE because Yuri Gagarin
satisfies description, hence “Neal Armstrong”
means Yuri Gagarin, and it’s true that Yuri
Gagarin was the first man in space!]
MMNS
Still, this is another important reminder that the
subjects of philosophy discussion cannot always
be resolved by philosophers (at least,
philosophers who don’t have labs and test
subjects). Sometimes philosophical questions
are empirical, and can’t be solved solely through
debate.