Entity Theories of Meaning. Meaning Talk Theory should make sense of meaning talk Theory should make sense of meaning talk What sorts of things do we

Entity Theories of Entity Theories of MeaningMeaning

Meaning TalkMeaning Talk

Theory should make sense of meaning talkTheory should make sense of meaning talk What sorts of things do we say?What sorts of things do we say?

Words and phrases mean things = Words and phrases mean things = have have meaningsmeanings

Synonyms Synonyms have have the same meaningthe same meaning Ambiguities Ambiguities have have more than one meaningmore than one meaning Meaningless things Meaningless things have have no meaningno meaning

Must there be meaning-things we can Must there be meaning-things we can have?have? Not necessarily, but let’s test the ideaNot necessarily, but let’s test the idea

Are Meanings Ideas?Are Meanings Ideas?

Matches our intuitionsMatches our intuitions What do you mean? = what do you have in mind?What do you mean? = what do you have in mind? To understand a meaning is to know what To understand a meaning is to know what

someone was thinkingsomeone was thinking Frege thought that a thought was the sense Frege thought that a thought was the sense

of a sentence (True or False was its of a sentence (True or False was its reference)reference)

Try this: Try this: For a term to have a meaning is For a term to have a meaning is for it to be associated properly with an for it to be associated properly with an ideaidea


What is an idea?What is an idea? Shifts the problem to Philosophy of Shifts the problem to Philosophy of

MindMind That may be the right place for itThat may be the right place for it But it doesn’t help us understand meaningBut it doesn’t help us understand meaning


Can this theory support compositionality?Can this theory support compositionality? Meaning of a sentence is the compositional Meaning of a sentence is the compositional

result of the meaning of the parts of a result of the meaning of the parts of a sentencesentence

The meanings of some sentence parts don’t The meanings of some sentence parts don’t seem to be ideasseem to be ideas

‘‘The pen is in my hand’The pen is in my hand’ What’s the idea for ‘in’ or ‘is’ or ‘the’?What’s the idea for ‘in’ or ‘is’ or ‘the’?

Assume some parts of sentences just Assume some parts of sentences just indicate how the composition is to be indicate how the composition is to be donedone


Can we get intersubjectivity?Can we get intersubjectivity? We want ‘dog’ to mean the same for everyoneWe want ‘dog’ to mean the same for everyone But my idea of a dog is not the same as your But my idea of a dog is not the same as your

idea (if only because it’s in my head not idea (if only because it’s in my head not yours)yours)

Perhaps we’re interested in ideas as Perhaps we’re interested in ideas as ‘types’ or ‘classes’‘types’ or ‘classes’ Compare a linguist’s interest in sentencesCompare a linguist’s interest in sentences But then these classes aren’t ideas but But then these classes aren’t ideas but

abstractionsabstractions

PropositionsPropositions

Take Take propositionspropositions to be whatever it is that to be whatever it is that makes two ideas (in sentences) the same ideamakes two ideas (in sentences) the same idea So my idea that Brisbane is the capital of QLD So my idea that Brisbane is the capital of QLD

expresses the same proposition as your (different) expresses the same proposition as your (different) idea that Brisbane is the capital of QLDidea that Brisbane is the capital of QLD

Try this: Try this: For a sentence to have a meaning For a sentence to have a meaning is for it to be associated properly with a is for it to be associated properly with a propositionproposition Still explains synonymy, ambiguity, Still explains synonymy, ambiguity,

meaninglessness, and intuitions about ideas in meaninglessness, and intuitions about ideas in same way as idea theorysame way as idea theory


Still allows compositionalityStill allows compositionality The parts of a sentence are termsThe parts of a sentence are terms The meanings of terms are The meanings of terms are conceptsconcepts

The concept of dog is the meaning of the The concept of dog is the meaning of the term ‘dog’term ‘dog’

Composition of concepts gives us Composition of concepts gives us propositionspropositions

Words such as ‘the’ ‘in’, … are guides to Words such as ‘the’ ‘in’, … are guides to the composition of conceptsthe composition of concepts


Still allows intersubjectivityStill allows intersubjectivity That’s according to the definition of That’s according to the definition of

concepts and propositionsconcepts and propositions

Possible WorldsPossible Worlds

Still need to know what propositions Still need to know what propositions areare

The common understanding is: The common understanding is: The The proposition expressed by a proposition expressed by a sentence is the set of possible sentence is the set of possible worlds in which that sentence is worlds in which that sentence is truetrue ‘‘The cat is on the mat’ is true in any The cat is on the mat’ is true in any

possible world in which the cat is on the possible world in which the cat is on the matmat


Compositionality Compositionality Turns out to be possible – if we treat composing Turns out to be possible – if we treat composing

operations as set-theoretical functionsoperations as set-theoretical functions Simple examples are logical operations:Simple examples are logical operations:

M(A or B) = M(A) union with M(B) M(A and B) = M(A) intersection with M(B) M(if A then B) = everything not in M(A), union with

M(B) There are also ways to combine concept-

equivalents But those ways are too complex to talk about here


IntersubjectivityIntersubjectivity Propositions and concepts are sets of Propositions and concepts are sets of

worlds and sets within those worlds worlds and sets within those worlds Sets are objective not subjectiveSets are objective not subjective


Structured propositionsStructured propositions Ambiguity is explicable and synonymyAmbiguity is explicable and synonymy But consider: the set of worlds where But consider: the set of worlds where

1+1+2 is true is the same set of worlds 1+1+2 is true is the same set of worlds where 2+2=4 is truewhere 2+2=4 is true

So 1+1+2 has the same meaning as So 1+1+2 has the same meaning as 2+2=4 ?2+2=4 ?

We need something elseWe need something else


Structured propositionsStructured propositions Solve that problem by including in Solve that problem by including in

propositions some structure propositions some structure The meaning of a sentence is the

intensional structure that determines the set of possible worlds in which the sentence is true

<M(=)<M(2)<M(+)<(M(1),M(1)>>> <M(=)<M(4)<M(+)<(M(2),M(2)>>>

This is like the ‘mode of presentation’ of the truth value (Frege’s sense)


Ockham’s RazorOckham’s Razor ‘‘Don’t multiply entities beyond Don’t multiply entities beyond

necessity’necessity’ Do we really want these things in our Do we really want these things in our

picture of the world?picture of the world? But they may be But they may be necessarynecessary

Gravity was a new entity but we accept it Gravity was a new entity but we accept it now because it is necessarynow because it is necessary


Causal PowerCausal Power We use the meanings of sentences to We use the meanings of sentences to

make things happenmake things happen Can structures of sets of possible Can structures of sets of possible

worlds have any causal effect in the one worlds have any causal effect in the one actual world?actual world?

How can we become associated with How can we become associated with structures? (We need to if we’re going structures? (We need to if we’re going to understand them.)to understand them.)

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Entity Theories of Meaning. Meaning Talk Theory should make sense of meaning talk Theory should make sense of meaning talk What sorts of things do we