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Philosophy of Language
Frege on Sense and Reference
Go0lob Frege (1848–1925)
• Invented modern logic • Introduced an approach and concepts which have a powerful influence in philosophy of language to this day
Review: Locke on Ideas
• Words are made meaningful by voluntary associaKon with Ideas
• Some Key Problems (very rough outline): – Providing a theory that (a) accounts for all types of word, (b) makes Ideas prior to language
– Allowing for communicaKon (privacy and subjecKvity)
– The ‘Unity of the ProposiKon’
Overview
• Towards Frege’s Account: ProducKvity; Unity; Truth and CommunicaKon
• Frege’s Account 1: Reference and Truth • A Crucial Problem: Frege’s Puzzle • Frege’s Account 2: Introducing Sense • Some Challenges, including: – ‘Empty’ names – Belief reports etc.
• Looking Ahead
Towards Frege’s Account: Produc;vity; Unity; Truth and
Communica;on
One Possible AlternaKve to Ideas: Simple Word–Object Theories
• See meaning in terms of relaKons between words and (public) objects (etc.)
• IntuiKvely plausible for proper names — ‘Brad’, ‘Everest’, ‘Italy’
The IntuiKve/‘Commonsense’ View
• ‘Proper names stand for objects’
‘Brad’ stands for
‘Everest’ stands for
‘Italy’ stands for
Problems for Word–Object Views
• ‘Stands for’ — What is it for a word to stand for an object?
• Words of troublesome kinds — ‘red’; ‘Kger’; ‘and’, ‘not’, ‘every’
• ‘The Unity of the ProposiKon’ — somehow, words work together to yield sentence meanings
Simple Word–Object Theories and The (Dis)Unity of the ProposiKon
• ‘Chris is warm’ ‘Chris is warm’
stands for stands for stands for
[Chris] [having] [warmth]
Two Related Problems
• The Unity of the ProposiKon
• ProducKvity: Speakers can understand sentences they’ve never heard before (even when no‐one has ever u0ered the sentence before) – How can speakers pull that trick?
The Beginnings of a SoluKon
• ‘Sentence meaning is fixed by the meanings of the words used and the way they have been put together (sentence structure)’
• Note 1: This is a theory, involving the idea that words have meanings (= constant contribuKons to sentence meanings)
• Note 2: So far, it’s just an outline of a theory
Another Key Idea: AsserKon and CommunicaKon
• How does communicaKon of informaKon via language work?
– Chris: ‘There’s £50 hidden over CD’s office door’
– You hear him
– You come to believe that there’s £50 hidden over his office door
But how?
Truth and CommunicaKon
• When speakers u0er a declaraKve (fact‐staKng) sentence, typically they present the sentence as true
• ‘There’s £50 hidden over CD’s office door’ is true if and only if there’s £50 hidden over CD’s office door
• Chris knows these things; you know these things
‘Truth CondiKons’
• (DeclaraKve) sentences have truth condiAons (condiKons under which the sentence is true)
• Terminology: ‘Truth value’ The truth value of a true sentence is true The truth value of a false sentence is false
So What?
• The Problem: So far, we’ve been trying to account for meaning (including sentence meaning) by appealing to supposedly meaning‐endowing enKKes (ideas, objects) but we couldn’t give a composiAonal account of sentence meaning — crudely, we have no idea how to sKck word meanings together to yield sentence meanings …
So What?
• The Pay‐off:
(It turns out*) We can give an account of words’ contribuKons to determining truth‐value (of sentences) …
… going a long way to solving the problems of Unity and ProducKvity
Frege’s Account 1: Reference and Truth
Frege’s Account 1: Reference and Truth
• Frege produced an account which combined a word–object element with the contribuKon‐to‐determining‐truth‐value idea we just looked at
• Key noKon: Reference (Bedeutung) — this can be seen as a specific refinement and development of our intuiKve noKon of standing for
Reference (Bedeutung)
Roughly:
Reference (Bedeutung) = the associaKon of a word with an item in virtue of which it contributes to determining the truth‐value of the sentences in which it appears
Reference and Proper Names
It’s plausible that
‘Brad Pi0’ (the name) refers to Brad Pi0 (the man)
Note that this is a theoreAcal claim — it accords with our rough‐and‐ready stands for intuiKons, but it needs to be shown to be correct in the context of a worked‐out theory
Aside: Terminology
• ‘Reference’ is oqen used to translate Frege’s ‘Bedeutung’
• ‘Bedeutung’ usually just means meaning in German, but Frege used it in the sort of special, technical way we’ve sketched
• ‘Reference’ is used both for the special relaAon to an item and the item standing in the special relaAon
More Terminology
• SomeKmes writers disKnguish reference and referent
• Reference — the being‐related‐by‐reference of an expression to the thing to which it refers
• Referent — the thing referred to
AlternaKve Terminologies: Some Warnings
• ‘Bedeutung’ is translated by some as ‘Meaning’ (with an upper case ‘M’, if you’re lucky) — it doesn’t mean meaning (loose sense)
• Some writers use ‘SemanKc Value’ for the special property and/or the item referred to
• Beware: some writers use ‘reference’ etc. in very loose ways, blurring theory and ‘common sense’
FuncKon and Object
• How does Frege address the problem of the unity of the proposiKon?
• Key: the noKon of a funcAon
• A funcKon takes us from a thing or things to some thing or things
FuncKons
• ‘the father of _’ — is associated with/expresses a funcKon which takes us from individuals to (their) fathers: – From Peaches to Sir Bob – From Stella to Sir Paul – From Michael to Kirk – From Paloma to Pablo And so on …
FuncKons and Reference
• Frege held that complex expressions have reference
• The reference of a complex expression is determined by the reference of its reference‐possessing parts (and how they’re put together)
• e.g. the reference of ‘the father of Peaches’ is the thing that the funcKon associated with ‘the father of’ takes us to when it takes the reference of ‘Peaches’ as input, i.e. Sir Bob
Reference and Truth
• Crucial Note: Given the way reference has been defined, if we take a sentence, and replace an expression with another with the same reference, then we won’t change the truth value
• SchemaKcally: if b is F, and b is one and the same thing as c, then c is F
A Concrete Example • ‘Marilyn Manson’ refers to
• ‘Brian Warner’ refers to
• But also, in fact, Marilyn Manson is (one and the same thing as) Brian Warner (the 2 names have the same reference)
• Suppose that ‘Marilyn Manson is a satanist’ is true
• ‘Brian Warner is a satanist’ will be true also
Predicates as FuncKons
• Consider simple subject–predicate sentences, e.g. ‘Chris is male’
• ‘Chris’ — grammaKcal subject, in this case a proper name
• ‘is male’ — predicate, intuiKvely a ‘characterizing expression’
• Frege extends the idea of (some) expressions expressing funcKons to predicates …
Predicates as Expressing FuncKons from Objects to Truth Values
• Frege holds that predicates express funcKons from objects to truth values …
• e.g. ‘is male’ expresses the funcKon which takes us – from Chris to True – from Julie to False – from Brad to True – from Angelina to False And so on …
Truth for Simple Subject–Predicate Sentences
• ‘Chris is male’ is true if and only if the funcKon expressed by ‘is male’ takes us from the reference of ‘Chris’ to True
• You might be worried about the funcKon being picked out in the way it is — To understand the predicate, does a speaker have to know that it’s the funcKon which takes us from so‐and‐so to True, from thingy to False, and so on? (More on this later.)
An Odd‐Seeming View
• Frege holds that whole sentences refer … • … and they refer to truth values ‘Chris is male’ refers to True ‘Angelina is male’ refers to False
• Frege doesn’t have to make this move, but it means his theory deploys a single central noKon (reference) and is unified (reference ‘is everywhere’ in the theory)
Perhaps not so odd …
• Remember – Reference = that in virtue of which an expression contributes to determining the truth value of the sentences in which it appears
• ‘Brad is male and Angelina is female’ is true if and only if both of ‘Brad is male’, ‘Angelina is female’ are true …
• So, it’s (only) the truth‐values of the sentenKal clauses which ma0er to the truth‐value of the big sentence
Logical Words
• NoKce that Frege’s account can accommodate ‘logical’ words like ‘and’ and ‘not’ …
• … Both are associated with funcKons from truth‐values to truth values …
• ‘and’ expresses the funcKon which – takes us from True and True to True – takes us from True and False to False – takes us from False and True to False – takes us from False and False to False
Summary
Frege: • Gives an account of (determinaKon of) truth‐value in terms of reference
• This account sees the truth‐value (reference) of a sentence as being determined by the references of the expressions which appear in the sentence
Linguis;c Turns in the Twen;eth Century
Half‐Day Conference Wednesday 20 May 2009 Physics Lecture Room 001
Hosted by the Centre for Modern Studies, in associaKon with the Centre for Research into ImaginaKon, CreaKvity,
and Knowledge (CRICK), Department of Philosophy Conference Starts 12.30, but the following session is recommended:
• 3.30–5.00 Peter Hacker (Oxford): ‘The Linguis;c Turn in Analy;c Philosophy’
A Crucial Problem: Frege’s Puzzle
Meaning in Terms of Reference Alone?
• It looks like we’re going to be able to account for determinaKon of truth‐value (for sentences) in terms of reference.
• Can we account for meaning enKrely in terms of reference and truth?
• Frege raised a puzzle which suggests not …
Frege’s Puzzle
• Frege puts his puzzle in terms of iden%ty claims, like
Marilyn Manson is (one and the same thing as) Brian Warner
• We can abbreviate these like this:
Marilyn Manson = Brian Warner
The Puzzle, 1
There are pairs of idenKty claims of the form a = a, b = a
where it’s true that b = a
but ‘a = a’ and ‘b = a’ ‘differ in cogni%ve value’
Example: Marilyn Manson = Marilyn Manson
Brian Warner = Marilyn Manson
The Puzzle, 2
‘a = a’ is trivial Someone who understood (grasped the meaning of) ‘a = a’ would know it was true on that basis alone.
Someone might understand ‘b = a’ and yet it come as news to them. (It might be a real gain in knowledge to find out it was true.)
So, it seems, their meanings can’t be the same.
The Puzzle, 3
• If we try to account for meaning in terms of reference alone, we have no way to account for the difference.
MM = MM BW = MM
Frege’s Account 2: Introducing Sense
An AddiKonal Component of Meaning
• Frege retains reference (Bedeutung) as a central noKon in his theory
• But he introduces an addiKonal component of meaning, sense (Sinn), to deal with Frege’s Puzzle
Sense
‘ … connected with a sign (name, combinaKon of words, wri0en mark), besides … the Bedeutung of the sign, [is] the sense of the sign, wherein the mode of presentaAon is contained’ (On Sinn and Bedeutung, p. 152, emphasis added)
Mode of PresentaKon
• A Mode of PresentaKon (MoP) is a way in which an object is presented to a thinker
• But this is just a rough characterizaKon — and as we’ll see, how we understand ‘mode of presentaKon’ will affect how we deal with other issues
Sense and Mode of PresentaKon
• The sense of an expression is the mode of presentaKon of its referent
‘Marilyn Manson’ (expresses) [Mode of PresentaKonMM] (Refers) (determines)
Sense, MoP, and Meaning
• Remember the idea of word meaning that we’ve been working with: word meaning is constant contribuAon to sentence meaning
• And for communicaKon, word meanings must be shared
• So, it would seem that, if sense is an aspect of meaning: sense of expression = MoP that a speaker is obliged to associate with the expression to count as understanding that expression (See Evans, VoR, p. 16)
Sense and Frege’s Puzzle
• Sentences with the same reference properKes can differ in their sense properKes
• Speakers can transmit real knowledge by exploiKng senses
• Result?
Mode of PresentaAon Again
But what is a ‘mode of presentaKon’?
What Frege says about MoPs can suggest a range of answers, e.g.:
• A way in which the referent is presented • A descripKon of the referent
• It’s not obvious these are equivalent
What’s a way in which the referent is presented?
• A perspecKve or point of view on the referent (see Frege’s example relaKng to a mountain quoted in the Evans piece in the study pack, pp. 14–15)
• A parKcular appearance presented by the reference (perhaps involving an ability to recognize) (Frege: ‘The sense … serves to illuminate only a single aspect of the Bedeutung’, OS&B, p. 153)
What’s a DescripAon of the Referent?
‘[The sense of “Aristotle” may be taken to be] the pupil of Plato and teacher of Alexander the Great’ (Frege, OS&B, p. 153, n. B)
[This idea will be clearer when we look at how ‘the’ phrases work later in the module.]
More about Sense: Sense and Thoughts
• For Frege, declaraKve (potenKally fact‐staKng) sentences express thoughts
• The sense of a sentence is the thought it expresses
• Frege’s noKon of a thought is meant to connect with our ordinary thought and talk about thinking and speaking; but again, it’s a special, technical noAon
Sentence Sense and MoP
• The sense of a sentence is a mode of presentaKon of a truth value
‘Chris is a satanist’ (expresses) [Mode of PresentaKonCiaS] (Refers) (determines)
False
Fregean Thoughts
• A (Fregean) thought is not an episode of thinking or a parKcular occurrence in someone’s mental life
• … rather, it’s a possible content of an episode of thinking
• So, there are Fregean thoughts which no‐one has thought
Thinkings and Thoughts
• If you think to yourself (now) Marilyn Manson is charming
• And I think to myself (now) Marilyn Manson is charming
• Then these are different thinkings (episodes of thinking), but they are thinkings with the same content (thinkings of the same Fregean thought)
Sense and Thoughts Again
• Frege’s puzzle doesn’t just arise for idenKty claims – Marilyn Manson is charming – Brian Warner is charming
• These expresses different thoughts • Test: Could a subject understand both and have one aztude (belief/disbelief/agnosKcism) to one and a different aztude to the other, without being irraKonal? If ‘yes’, they express different thoughts and have different senses.
Sense and ObjecKvity
• Frege disKnguishes senses from ‘ideas’ • ‘Ideas’ here are internal, private mental items, e.g. my ‘internal image’ of an object (OS&B, p. 154)
• Senses are meant to be public and objecKve • We can (perhaps) make sense of this in terms of MoP as perspecAve or way in which the referent is presented (See Frege’s telescope analogy, OS&B, p. 155)
Sense, Predicates, and FuncKons
• Recall the worry about predicates referring to funcKons — to understand ‘is male’, do I need to know that it’s the funcKon that takes us from Chris to True, Julie to False, … ?
• The introducKon of sense seems to help with this worry — I just need to associate the right sense which determines this funcKon
Some Challenges Faced by Frege’s Account
Challenges to Frege’s Account
• The Nature of Sense • ‘Empty’ Names (names that don’t refer)
• Belief A0ribuKons (and other odd cases) • What Makes Words Mean What They Do?
• Understanding Others
The Nature of Sense
The Challenge:
Can we extract from Frege (or develop) a characterizaKon of sense which makes clear what it is, allows it to do all of the jobs we want it to, and is coherent?
Empty Names
• In Frege’s account, the meaning of proper names is explained in terms of reference — a relaKon between the name and an object
• Basic Problem: There seem to be names which are meaningful, but which do not refer — so‐called ‘empty’ names
• Possible examples: ‘Sherlock Holmes’, ‘Santa’, ‘Vulcan’, ‘Fuzzy Dunlop’
Why Are Empty Names a Problem?
• Our semanKc theory can’t include a true reference clause for the name (so Frege can’t present a semanKcs which both treats empty names like other names and is true) ‘Vulcan’ refers to _____ (!!!???)
• Trouble for Frege’s account of predicates and sentences — no object, nothing for funcKon to apply to, no truth value determined
• Trouble for sense (on some ways of understanding it): Difficult to see how we can have a way of presenAng if nothing is presented
Belief Reports and Other Fun Stuff
• Reference = power to contribute to determinaKon of truth‐value
• So, if we keep reference the same, truth‐value should stay the same: MM is tall (now) True MM = BW True, names have same ref BW is tall (now) Will be true too, so OK
• But …
Belief Reports
• Suppose David believes that MM is tall (now)
MM = BW (Ref ‘MM’ is the same as Ref ‘BW’)
• But, it’s not guaranteed that David believes that BW is tall (now)
… and worse
• According to Frege, sentences refer to truth values …
‘MM is tall (now)’ refers to True
‘Lima is the capital of Peru’ refers to True
But we can’t subsKtute in the belief report and be sure of no change in truth value:
David believes that Lima is the capital of Peru
Frege’s SoluKon
• Frege: Belief reports are special cases …
Words (and sentences) in the embedded sentence don’t have their usual reference, instead they refer to their usual senses
• Example: In ‘David believes that MM is tall (now)’ the words in ‘MM is tall (now)’ refer to their usual senses
A Problem for Frege’s SoluKon
• If words in embedded sentences refer to senses, they must do it via a sense
• But we need to associate the right sense (David’s favourite thought may be the thought that MM is tall (now), but ‘David believes that MM is tall (now)’ and ‘David believes David’s favourite thought’ express different thoughts)
• But then we’d need to have learned the right sense • But belief reports can be iterated … ‘Tom believes that Barry believes that David believes that MM is tall (now)’
• Do we learn infinitely many senses? How?
Challenges for Later
• Frege effecKvely says that words are meaningful in virtue of having senses, but says li0le about what it is for someone’s words to have the senses they do
• Frege says even less about how we could know what senses someone a0ached to their words
• Given his interests, that’s ok for him, but we might want to say more
Looking Ahead
For Later …
• Can we make sense of sense? Can we fill out the noKon of Fregean sense in a coherent and saKsfying way?
• Do we really need to posit sense as an ingredient or aspect of meaning?
• To pursue these quesKons, we’re going to look more closely at how proper names and ‘the’ phrases work