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Primary: Putnam, H. (1975) 'The Meaning of 'Meaning'' Kripke S. (1972) ‘Naming and Necessity’.
Secondary: Lycan, W. G. (2000) Philosophy of Language, London; Routledge.
Devitt, M. & K. Sterelny (1987) Language and Reality,
Cambridge, MA; MIT Press Evans,
Gareth (1973) ‘The Causal Theory of Names’ in Schwatz, S. (ed.)
(1977) Naming, Necessity, and Natural Kinds, Ithaca NY; Cornell UP, pp.
192-215.
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Kripke's Theory
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Recall
that I said that there were two parts to Kripke’s theory of reference.
The first part of this theory is a tale that he tells about what the
semantic role of referring terms is supposed to be. What do they
contribute to the meaning of the larger linguistic items in which they
participate (principally sentences?) The second part, independent of the
first, is a theory about just what
it is that makes a word refer to the thing to which it refers. What is
it – in the real world – that establishes a relationship between those
two things; or, what is the nature of this relationship. I hope that you
can see that the two types of question are really very different. If
we’re just considering description theories, I grant that it’s easy to
become a little bit confused about this distinction – as I think the
early description theorists may have done – because (i) the role of the
referring term in a sentence is just the role of the description, whereas
(ii) the link between the name and the object said to be just that the
object is the unique satisfier of that description; and so, the
explanation is very similar in answer to both questions. We have to
suppose that the answers would have to be very different in the case of a
direct reference theory. In any case Kripke’s answer to this second
question is fairly straightforward. Thus: A
name refers to something because there is a causal relationship between
the use of the name and the thing to which it refers.
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Suggestive Problems
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Some
such idea as this is suggested by two fundamental problems with the
stories that we’ve been telling about reference so far. a.
Self-Containment of Descriptions We’ve
been looking in past lectures at various forms of theory of meaning for
names, where the problem as we’ve conceived it is to understand what it
is about names that regulates the way that they mean the things that they
are supposed to mean. The description theory – in one way of
understanding it anyway – claims that the meaning of a name is just the
same as the meaning of some definite description, and the discussion has
centred on the controversial consequence that any implication that can
legitimately be drawn from sentences using names should be equally
legitimate when some occurrences of those names are replaced by their
corresponding definite descriptions. We think that that turns out not to
be the case. But even if it did turn out to be the case, how far would
that get us? Consider
what a description consists of. In the case of Aristotle, for example, the
description would be ‘the teacher of Alexander’, plus a bunch of other
stuff maybe. But this description appeals to terms like ‘teacher’ and
‘Alexander’ which are themselves in need of explanation. Perhaps
‘Alexander’can be equated to ‘the pupil of Aristotle’, but this
would lead us to an obvious definitional loop – which is another problem
you can chalk up to description theories it seems to me that there are
likely to be lots of names that are only known with respect to these sorts
of loops.
Pegasus = winged horse that Bellerophon rode and lived on Mt
Helicon
Bellerophon = guy who rode Pegasus
Mt Helicon = where Pegasus lived Going
back to the original problem, a bigger difficulty is trying to define
‘teacher’. Unless you’re going to define it as the thing which
‘Aristotle’ and ‘Stephen’ and … all other teachers have in
common (also circular, this time in two different ways) you’re going to
have to define it in other general terms, and you know – because your
dictionary is of finite size, that somewhere this definition too is going
to start getting circular. Somehow we have to break out of this circle,
but the description theories give us no clue how to do this. b.
The Mystery of Senses On
the other hand, if the meaning of names is somehow to be explained in
terms of sense, we have to have some idea of exactly what a sense is.
Frege, as we saw, has a variety of different understandings of what sense
is, but the principal concept is that it is a ‘mode of presentation’.
OK. So what is meant by a ‘mode of presentation’?, and how is it that
this adds something to the name that is distinct from its function of
reference? We could suppose that the MOP is some type of abstraction, but
this would make it still mysterious how the abstraction did its work. What
we really want, if we’re going to appeal to senses is some way of
explaining them in terms of the other sorts of things that we accept exist
in the world. We want, in short, to have a theory of meaning that appeals
only to the sort of entities that exist in our scientific theories.
Physical causes and histories are just the sort of thing that we’d be
looking for, so a theory that claimed to be able to account for meaning in
those terms is well worth looking at.
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The Causal Theory of Reference
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Any
theory of reference of the kind that we’re now considering has to
account for at least two things: in the first place, it has to account for
the manner in which a name first becomes attached to an object; and, in
the second place, it must be able to explain how it is that people not
present at the naming and not acquainted with the object can use the name
to refer to it. So let’s talk about that. a.
Baptism The
event which fixes the reference of a term – typically a new term – is
called its baptism or a dubbing. The theory which tells us how the
baptism/dubbing works is a theory of reference
fixing. We can start by describing the standard form which such an
event takes. Let’s
suppose that we want to name our dog ‘Fido’. In the presence of the
object to be named, the person doing the naming points at the object and
says, ‘this is called ‘Fido’’. We can see that in this case there is
some sort of causal link between the object and the term. Just being
present and observing the object involves a causal linkage between the
object and the observer, and the observer seeing the object and pointing
at it and saying ‘Fido’ is a chain of events distinguishable from
other events in term of the causal links between the observer who makes
this ostensive definition of the term and the object whose name is being
defined, and the utterance of the name term itself. In this
standard/normative case the introduction of the term is by ostension. The
baptism is not only effective for the person doing the actual pointing and
naming. We have to imagine that anyone else who was also present at the
dubbing event, and who has the required linguistic abilities, would also,
in virtue of their observing that event, gain the ability to refer to the
object using the name ‘Fido’. This too is to be understood in terms of
the causal links that exist between the observer of that event and the
participants in that event – she hears the word ‘Fido’, she sees the
object Fido, she’s sees the pointing of the finger at Fido, and so on. b.
Reference Borrowing But
what about those people who did not observe the original event? Most of us
here were not present when each of us were given our names (I mean Bob
wasn’t there when Carol was named and Carol wasn’t there for Bob
either) and yet we have no difficulty in using and understanding those
names. What can account for that ability? Apparently, the story goes that
those not at the original baptismal event obtain their ability to refer to
the object using its name from other speakers who already possess this
ability, and the ability of all speaker who use the name successfully can
eventually be traced back to one of the participants in the dubbing. I can
talk about Napoleon, because I have read about Napoleon in a book, and
I’ve gotten my referring ability via that channel. The author of the
book may have heard about Napoleon from a lecturer. The lecturer may have
heard stories told by his relatives. The relatives will have heard from
other folks. And some of those folks, somewhere along the line, wil have
seen Napoleon being pointed to and addressed as Napoleon, and so on …
all the way back to Mrs Buonaparte saying ‘What a lovely little boy.
I’ll call him Napoleon.’ Each
of those interactions is – we have to suppose – distinguishable as a
causal relationship. In each case the causal linkage is such that the name
use of the name is linked in the appropriate way to the object … and
appropriate here just means that its linked in just the right way so that
it does refer. So
here’s the story as Kripke describes it for a baby in N&N: 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 else where, 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. He knows that Feynman was a
famous physicist. A certain passage of communication reaching ultimately
to the man himself does reach the speaker. He then is referring to Feynman
even though he can’t identify him uniquely. You’ll
notice here that there’s nothing required to be known about Feynman for
the reference to succeed. The final speaker may have nothing but false
beliefs about Feynman, but if the causal linkages that are in place are of
the correct sort then he can successfully refer to Feynman. If a friend
asks you ‘what is a manatee?’ and you answer by describing cattle in
Bolivia, you not only give yourself much innocent pleasure but you also
allow them to refer successfully to manatees in the future. Is that right,
do you think? Or would a description such as that constitute a causally
effective reference fixing process that would result in a redubbing
of the manatee. We’ll get back to those sorts of questions a bit later.
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Advantages of the Causal Theory
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With
any theory there are going to be pros and cons. We’ll start by having a
look at the points in favour of this one. a.
Explains Sense You’ll
recall that we decided that Frege may well have been on the right track
about how to solve the problems that arise for direct reference theories:
that there is more to the meaning of a name- for example – than its
referential function, there is also something like its sense. One of the
major difficulties with the Fregean view of sense, however, was that we
couldn’t think of any way of instantiating such a property in the real
world. But now, if we take sense to be something like the ‘mode of
presentation’ that Frege generally claimed it to be then we have a
plausible candidate for that semantic object in the causal chain that is
attached to each term and links it to the thing it references. &nbs˙˙ i.
You
can see how this would work. Given two names that have the same reference
like ‘Hesperus’ and ‘Phosphorus’ or ‘Tully’ and ‘Cicero’
we can distinguish the two by saying that the causal chain that links my
use of the word ‘”Hesperus’ to Venus and my use of the word
‘Tully’ to the famous Roman orator are quite different from the causal
chains that link my use of ‘Phosphorus’ to Venus and ‘Cicero’ to
the orator. Thus, if the causal/historical links to the reference of a
sentence (whatever that might be) is the compositional result of the
combination of words in the sentence, then in sentences which differ only
in that some of the component words have different causal/historical
chains connecting them to their referents we can expect that there will be
a corresponding difference. ii.
More
than this, it looks as if the ‘mode of presentation’ is a pretty good
description of what we actually think will turn out to play the essential
role in these causal chains. It’s not likely that every causal linkage,
however, indirect or contingent, is going to play some essential role in
the causal/historical reference fixing procedure we’re talking about.
It’s not likely that both myself and the dog being in sunlight, or my
smelling the dog, or my hearing him bark, are the sorts of causal linkages
that are going to be relevant to either dubbings or reference borrowings. iii.
We
can also see that a causal/historical link of the right sort has other
characteristics which were supposed to belong to the sense. For example,
it was claimed that sense determines reference, and it is certainly the
case that if you have a causal/historical chain that links the use of a
word at one end of it, with an object at the other end, and this object is
supposed to be the reference of the word, then there is a very definite
sense in which the chain determines the referent of the word. It
determines it just by having the word at one end and the object at the
other. iv.
Finally,
sense was supposed to be the essential thing for Frege in understanding
the meaning of a word. It’s only if you have some special cognitive
relation to this object ‘sense’ – which Frege called ‘grasping’
it – that you can be said to understand. Or rather, the very fact of
your understanding is said to consist
in your having this relationship with the sense. Well, as far as the
causal/historical linkage goes, you can only be held to understand a word
if your usage is properly placed in a causal chain linking word and
object. It is fairly clear that some part of this chain is going to have
to pass through the brain/mind of the language user. At various places in
the explanation of how the causal/historical story of sense goes we’ve
been mentioning as one of the qualifications the the user involved has to
have a certain degree of linguistic sophistication. You can see why this
is the case if you consider whether the dog that I baptize ‘Fido’ will
perceive this as a baptism and will have the appropriate causal connection
that will account for its use of the word ‘Fido’. I think not. Now,
this ‘linguistic sophistication’ of which I speak,, which may also be
thought of as language competence, is the sort of thing that results from
causes in the brain. These causes are therefore essential to the story.
The possession of particular causes of this sort by the word user can be
thought of as constituting his ‘grasping’ of the sense. (It’s like
he’s got hold of a chain somewhere in the middle links, in virtue of
their passing through his head.) b.
Looks like language Recall
the things that we said were characteristics of language. This story about
causal/historical chains allows us to account for a great many of them. i.
In
the first place, we can see that the characteristic of stimulus independence is explicable, because whatever it is that
leads to the emitting of a word like dog, it is not necessarily the
presence of dogs or dog-like thing, or even reliable indicators of
dog-presences. The causal chain is
sufficiently generally described that the very absence
of dogs could equally
well be a stimulus for the use
of the dog word (as in ‘where’s that darn dog
when I need it.’) ii.
The
characteristic of medium
independence is explicable, because it really doesn’t matter in what
‘medium’ the word is transmitted in order for there to be an
appropriate causal/historical chain linking the use of that word (in
whatever medium) to the object that it’s supposed to refer to. I can
write ‘come here, dog’ on a piece of paper and it will be ineffective
as an actual command, but no competent language speaker will fail to grasp
the meaning of it, nor will it fail to refer. iii.
The
connection between word and object is arbitrary,
just as we required, because the causal/historical connection does not
depend upon the form of the utterance in any respect but only to the form
of the dubbing ceremony or the reference borrowing processes, such that
they provide the right causal/historical links in the chain. I can call
all dogs ‘boggles’ for all the difference it’d make to the referring
capacity of my language. iv.
The
abstractness of names is
explicable because the name does not depend upon any of the
characteristics of the object in order to refer to it. Pictures, for
example, don’t have this capacity because they rely upon a sufficient
set of analogous structures in the representation to the object
represented; and we might suspect that the description theory could also
be seen as having difficulties in this respect. In the causal/historical
story, there is no need to refer to properties of the object in order to
construct an appropriate link between it and the word. Recall
that the other characteristics of language in general (as an abstract
object) that we were interested in were power, productivity and
systematicity. The causal/historical view doesn’t give us any real
assistance here, but there don’t seem to be any reasons to think that
the story is actually incompatible with languages possession of those
characteristics. We may legitimately assume that they will be explained by
some future refinement of the theory. c.
Solves the four puzzles of reference We
also need to be sure that the new theory is at least as capable as the
Fregean theory or the Russellian of solving the sorts of problems that I
have been taking as bellwethers for theories of reference or of language
more generally. i.
We
need to explain why it is that two identifying statements like Venus
is the evening star Venus
is Venus can actually have different meanings or cognitive
significances while the only difference between them is that different
referring terms are used to refer to the same objects. You’ll remember
that on the Millian View of direct reference – and possibly also on the
Kripkean view – these got their meaning from the meaning of their parts,
and the meaning of the parts ‘Venus’ and ‘evening star’ was no
more than their reference, and their reference is identical, and so the
two sentences should mean the same. The causal/historical story also takes reference to
be essential to the meaning of referential terms, but the fact of these
terms referring is explained in terms of their linkage to the objects by
some chain of causes. This chain can be used to distinguish two different
terms that refer to the same object, just as sense was supposed to do for
Frege. The link from ‘Venus’ to Venus is different from the link from
‘the evening star’ to Venus, therefore the person who understands the
first sentence has to be able to cope with two different causal chains
connected to Venus, whereas to understand the second sentence he only
needs to be able to cope with one. (Note that I’m not claiming that he
has to be able to cope with the causal chain connected to Venus in order
to determine whether the second sentence is true or not. That doesn’t
require any understanding of the referring term at all.) ii.
We
have to be able to explain how it is that we can make meaningful
statements that appear to refer to objects that don’t exist. How is it
that we can say something like Pegasus had a glossy white coat And be in no danger of saying something meaningless?
If the meaning of a sentence is derived from the meaning of its part, and
one of those parts has no meaning because it has no reference, then the
sentence should be meaningless. In this sort of case the causal/historical theory
claims that although there is no actual object to which a causal chain
from ‘Pegasus’ can be attached (in the way that causal chains need to
be attached in order for them to refer) this does not mean that there is
no a highly analogous causal chain attached that can play much of the role
of sense-giver that the designational causal chains play for actually
referring terms. Consider how a typical such causal chain arises: someone
dubs a thing by a name and then by the use of that name in conversation
and writing and so on a lot of causal links arise that allow others to
become part of the causal chain that eventually can be traced back to the
object named. In the case of these fictional names the name is introduced
to conversation by some fabulist and lacks an object which is to be the
subject of a dubbing, but the rest of the causal connections deriving from
the conversations and writings that use that name are exactly the same as
in the standard case – and therefore is claimed to play the role of
sense equally effectively. You may wonder whether this should be taken to
suggest the idea of a chain fixed at one end only (by the term) and with
the other end thus free to flail about doing all sorts of referential
damage. This is not necessarily the case. Consider how the name
‘Peasus’ is introduced: someone says ‘There is a wonderful creature
that is just like a horse but it has wings and can fly.’ In such an
introduction the storyteller is giving a description which has a meaning
and a sense because the referring terms in it, ie. ‘horse’,
‘wings’, do refer – though they refer in this case to abstractions,
which is another story. In short, it’s because of this grounding of the
introductory description that ‘Pegasus’ can be said to be
referentially fixed. Just note also that this story gives a good reason
for distinguishing between names that are fictionally based like
‘Pegasus’ and names that are just nonsense syllables like the
‘Jabberwock’ or ‘borogoves’ in the Lewis Carroll poem. Names like
those don’t seem to be introduced by descriptions and so they don’t
have any grounding at all and so you’d probably claim that they didn’t
have meanings/senses. Does this mean that sentences that use them are
meaningless? Do you think that the lines
Beware the Jubjub bird, and shun
The frumious Bandersnatch Are meaningless? iii.
We
have to be able to explain how it is that we can make meaningful
statements that appear to deny that something exists. You’ll recall the
problem there for direct reference theories: if your statement denying
that Pegasus exists is true then the statement refers to a non-existent
thing so there is a failure of reference so there is a failure of meaning
so the statement is meaningless. It can only be meaningful if it is false.
Inconceivable! But the same story that explains why reference to
nonexistent fictional creatures is meaningful will suffice to explain why
existence statements that refer to them will be meaningful. The
nonexistent thing being referred to is not at the root of the causal chain
attached to the term ‘Pegasus’, but there is
a chain and it is grounded and so there is a sense-analogue for the term
and so it can be said to be meaningful and so the sentences truly denying
its existence can be meaningful. They are meaningful in just the same way
that sentences falsely denying the existence of me are meaningful. iv.
The
final problem that we need to be able to deal with is the problem of
reference in opaque contexts. It’s unfortunate that this turns out to be
a fairly tricky problem for causal/historical theories. Those who are
interested in seeing how this turns out could have a look at Michael
Devitt’s (1981) book Designation
where he has a go at working out what’s going on.
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Problems for the Causal Theory
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I’ve
done enough advertising for this theory now. It’s time to have a look at
some of the problems that people have thought that such theories face. A
lot of these problems were brought forward by Gareth Evans – not the
former Australian foreign minister and present head of the International
Crisis Group, but a quite different Australian. (Same name, different
referent. How does the causal/historical theory handle something like
that?) a.
Change of reference The
first problem to look at is the problem of change of reference. We are all
aware of the fact that words can begin by referring to one thing and
finish up referring to some other thing. The example that Evans gives is a
report that “In the case of ‘Madagascar’ a hearsay report
of Malay or Arab sailors misunderstood by Marco Polo … has had the
effect of transferring a corrupt form of the name of a portion of the
African mainland to the great African island.” He
also has a simpler example that we can use: Two babies are born, and their mothers bestow names
upon them. A nurse inadvertently switches them and the error is never
discovered. It will henceforth undeniably be the case that the man
universally known as ‘Jack’ is so called because a woman dubbed some
other baby with the name. The
problem is that the dubbing is pointing at one object originally and yet
through various historical events it seems that the reference has switched
to some other object. How can this be the case if the reference is
determined by the original dubbing event and this original dubbing event
is not changed – in the way that all past events can’t be changed. The
standard response to a difficulty such as this is to suppose that the
causal/historical chain that connects a name to its bearer is actually a
whole lot of chains: the claim would then be that there are typically several
chains that are connected to the object that reach to the term that names
it. You can see why that would be a plausible claim to make because it’s
not usually the case that an object is pointed at and named on just one
occasion and all other references are purely derivative of that event.
Consider this, for example: Aurelia, who’s one of the lecturers here,
has just had a baby; she brought the kid in to show us how well she’d
done, and while she was here she was asked what it’s name was several
times, and each time she answered ‘He’s called Guy.’ It seems to me
that each of those episodes is going to be at least as referentially
significant as the original dubbing event – certainly they’re going to
be more referentially significant to anyone who was not present at the
original event. They play, for me anyway, the role of dubbing event. All
my subsequent referrings to this baby – though there will not be many
– will take their referential power from the causal chain that is
grounded with Aurelia’s statement in the presence of myself plus the
baby. This
idea of multiple grounding of
reference in the object then allows an explanation to be given of
reference change such as we had in those two examples. How so? Because it
allows for there to be groundings that are inconsistent with an original
dubbing. The baby Jack in Evans’s example is confused with the baby Jim.
The original referential role of the dubbing event upon the other baby –
let’s call it Jim – is transmitted through just one causal chain, but
the large number of subsequent grounding of the name Jack in that baby are
able to overwhelm the referential significance of that original dubbing is
that the baby can really be said to have been named Jack. Something
similar happens with the Madagascar example. In that case however you may
find that there are two communities of speakers who are using the words
with different causal chains attached to them. One bunch, the original
users of the term are using it to refer to part of the African mainland,
while another bunch, who got their use through reading Marco Polo, are
referring to the island. Who is right in this case? Couldn’t they both
be right? There may be a period of confusion if the two groups ever had
occasion to talk to each other about Madagascar, but this would be exactly
what we should expect. We really do have experiences of such confusions,
so it’s a point in favour of the causal/historical view that it tells us
how such things are possible and how they come to be resolved.. b.
The quâ-problem Another
difficulty, which is not so easily gotten around, goes by the name of the quâ-problem.
Consider this: I point at an object, for example, a dog, and I say ‘Lo!
This is called Fido’. I then take it that I have named this object, this
dog, Fido. But what is it that distinguishes this naming event from the
naming event where I point at a dog and say ‘Lo! This is a called a
dog.’ How does it turn out in the first case that the causal anchor of
the referential chain is laid in the particular dog I called Fido, whereas
in the second case the causally relevant division of the world is all
things that are dogs? How, indeed, did it turn out that in the first
instance I was taken to be pointing at the whole object – the dog qua
dog – and not at the dog’s nose and had thus named the dog’s nose
‘Fido’, or perhaps the wetness of the left nostril, or perhaps a time
slice of the dog’s passage through the space-time continuum, or etc.? Now,
it is a fact that names don’t typically point at any of those other
things, but it is another fact that they could. We could very easily come
up with names for such things and ground them in what would apparently be
the very same ‘object’. This sort of thing strongly suggests that
there is something about the grounder
himself that is relevant to what is really the object that is being
baptized. The obvious thing that could be different in the person doing
the grounding and responsible for the type of grounding that occurs, is
the thing that we are sure is different in the grounder; that is, the intention of the person doing the grounding, by which I mean their
mental state of intending to refer to the dog
rather than to time slices of the critter. What
this means is that there has to be something like a description involved
in the baptismal event. A description is required to make the claim that
one has an intention to point at an object of a particular kind rather
than of some other kind. It is not necessarily a uniquely identifying
description of the object in the sense that the descriptions proposed by
Russell and Searle might have been, but it does mean that we can’t
really think of the causal/historical theory as completely unrelated to
the description theories that we are intending to replace. There is some
degree of descriptivism required to make it work.
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Natural Kind Terms
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There
are plenty of other possible problems that can be found with the
causal/historical view of reference, but those two will do for the time
being. Let’s take a look now at yet another extension of the basic
causal theory. We’ve
now seen a few cases in which the causal/historical story relies upon an
ability to name more general classes of objects. When we were looking at
the talk about fictional objects like Pegasus we supposed that the
original grounding involved descriptions of wings and horses and not
ostensions of any particular wing or horse. Similarly, we have just seen
that the solution to the qua-problem for the theory involves some sort of
descriptive element in which the kinds of things being referred to are
specified. The natural next step for the causal/historical theory would
therefore seem to be to see if it can be applied to the naming of natural
kinds. The sorts of natural kinds that are used in this discussion are
those that were used by Kripke and Putnam (in your readings); thus we’ll
be talking about gold, water, and tigers. a.
Problems for Description Theories of Natural Kind Terms Let’s
remind ourselves that the theory that Kripke and Putnam were trying to
replace was basically the descriptivist theory, and the story that that
theory told about the meaning of natural kind terms was that it was given
by a description or a description-cluster of the properties of the natural
kind. Thus gold, say, was to be described as a a heavy, yellow, noble
metal; and water is a colourless, odourless, potable liquid; and a tiger
is a wild, striped, feline. Kripke and Putnam point out that there are
very cogent criticisms against this view of the meaning of natural kind
terms – in fact they’re pretty much the same type of criticism as they
made against the descriptivist theory of names. In particular they make
modal arguments against all such descriptions: for any such description we
can conceive the situation that (ie. there is a possible world in which)
the description fails for members of that natural kind. For example, gold
could have not been yellow, water could have not been odorless, and tigers
could have been only striped because the freemasons had painted them that
way for their own nefarious purposes. There are also problems with
unexpectedly trivial statements like ‘water is potable’, which turns
out to be tautologous in this case. These
are serious difficulties indeed, but the most
serious difficulties – possibly fatal
difficulties – arise when we consider that the descriptivist theory
of natural kind terms, like that for names, requires a good deal of
knowledge on the part of the user for their intention to refer to a
natural kind to be achieved by their using the name of that kind. Putnam
makes the point that he cannot reliably distinguish an elm tree from a
beech tree because he does not have, either explicitly or implicitly, the
knowledge in the form of a description that would suffice to identify
either natural kind. Yet when he says that elms are trees or when he hears
others talking about elms in autumn leaf he is surely referring to elm
trees and he is surely being told about elm trees. Thus identifying
knowledge is not necessary for successful reference and to grasp the
meaning of a term. On
the other hand, identifying knowledge is not sufficient either. Devitt and
Sterelny give the example of the discovery of a creature that satisfies
all the identifying descriptions of Pegasus. It’s a real flying horse.
Perhaps it was bred by the Freemasons in a secret gene splicing factory in
Tibet., If so, it is not the Pegasus to which we were referring. (And this
is not necessarily because our description includes the word
‘mythological’, other non-mythological examples could be given. The
point is just that no reasonable description is going to complete enough
to specify only the thing to which we wish to refer and no other possible
object. Or kind) This
is an appropriate point at which to introduce you to the famous TwinEarth
argument by Putnam. It may be taken as an argument against the possible
adequacy of descriptive theories in the original Russellian sense. Imagine
that there is a world far far away from Earth, but a world in the same
universe as Earth – not a merely ‘possible’ world then – and this
world is a near duplicate of our own familiar planet. A casual observer
would see the same plants and animals and seas and continents, and even
the same people speaking the same sentences in the same language. In fact,
however, TwinEarth differs from Earth in that whereas water on Earth is
made of H2O, what the inhabitants of TwinEarth call ‘water’
is made of XYZ. Now, XYZ is a colourless, odourless, potable liquid and
has all the other properties that a seventeenth century Englishman would
have given to the thing he called ‘water’. But ‘water’ despite the
identity of the descriptions does not mean the same thing on TwinEarth as
it does on Earth, because it points to XYZ rather than H2O.
This indicates the failure of the description theory to determine
reference properly. It also indicates, that the descriptions as
instantiated in someone’s head, their thoughts or intentions, can’t be
identically referring either; and therefore, because the heads of the
speakers are otherwise identical, it appears that meaning cannot be
defined entirely in terms that do not reach beyond the mind of the
speaker. As Putnam puts it, meanings just ‘ain’t in the head’. b.
The Extended Causal Theory So
what is it that Kripke and Putnam say makes water water, gold gold, and
tigers tigers? Well, they claim, it is just the scientific
natures of those things. In the case of water, it is the fact that it
is composed of H2O; in the case of gold it is the fact of its
being 79Au; in the case of tigers, the fact of their having a
particular genetic coding. But this, you may object, hardly seems likely;
after all, couldn’t it be the case that in some possible world water was
other than H2O, gold other that 79Au, tigers other
than the very genetically definite creatures that they are? Kripke and
Putnam say no. There is no possibility of water being other than it is;
there is only the possibility of one’s being ignorant of what it is. The
reference fixing part of the extended causal theory appeals to this claim
of direct reference by Kripke and Putnam in order to establish that there
is a real sense in which there is an unambiguous natural kind at the base
of the chain. The chain for ‘water’ is established by pointing at
several instances of water. It then turns out that the causal chain is
grounded in (refers to) the natural kind formed by the scientific
description of the attribute that defines the similarity of all those
examples that were pointed at. (Note that the science that lies behind the
naming of natural kinds is just the same science that uses those natural
kinds to establish its laws, so the process is not so unlikely as it might
at first appear.) The
rest of the causal/historical story is much the same as for naming
particulars, so we don’t need to repeat it all here. You may also wonder
whether the problems that were suggested to exist for the singular version
of the causal/historical theory could not be repeated for this more
extended version. I’ll leave that for your own consideration.
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