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This repeats something we’ve already done but in Frege’s words. When Frege was writing, he didn’t know about superman (it hadn’t been created yet). So instead he focussed on a film called ‘The Long Kiss Goodnight’.

Samantha Caine

Suburban homemaker and the ideal mom to her 8 year old daughter Caitlin. She lives in a New England small town, teaches in a local school and makes the best Rice Krispie treats in town.

Charly Baltimore

a highly trained secret agent and cold-blooded killer involved in the government's most unscrupulous affairs.

‘Charly is Charly.’

‘Charly is Samantha.’

‘What is stated in the proposition ‘Charly is Samantha’ is certainly not the same thing as the content of the proposition ‘Charly is Charly’.

‘Logic makes me die inside’

‘You have to turn your headlamps on
when it’s raining in Sweden.’

How do I know it’s raining in Sweden
Not everyone agrees about this. Consider for instance Devitt and Sterelny’s 1999 textbook.

‘the core of a sentence’s meaning is its truth condition; that is, the property of a sentence which, together with the world, makes it true or false.’

Devitt and Sterelny, 1999 p. 11

In this course I'm also speaking as if sentences were truth bearers. (Sorry!)
sentence vs utterance

But what are utterances?

They’re actions which typically occur in, and are constitutive of, lingiustic communication. Hard to define because not all utterances are communicative.
Part of the point is to avoid distinguishing oral and manual communication.


Is timeless.

Can be uttered by different people.

Is a structure of words.

Cannot express a proposition (strictly speaking).


Has a date.

Has a particular utterer or utterers.

Is a structure of events.

Can express a proposition.

But what are propositions?


... are the things that can be true or false;

... and the things that utterances characteristcally express.

‘What is stated in the proposition ‘Charly is Samantha’ is certainly not the same thing as the content of the proposition ‘Charly is Charly’.

Now if what corresponded to the name ‘Samantha’ as part of the thought proposition was the reference of the name and hence the woman herself, then this would be the same in both thoughts propositions.

The thought proposition expressed in ‘Charly is Samantha’ would have to coincide with the one in ‘Charly is Charly’, which is far from being the case’


Frege, 1892[1993] p. 44

You’re gonna be writing an article on this. Link what is written here to the Observation on handout from lecture 10

Charly Baltimore lives in New England

Samantha Caine lives in New England

‘Someone who takes the latter to be true need not … take the former to be true

‘An object can be determined thought of in different ways, and every one of these ways of determining thinking of it can give rise to a special name, and these different names have different senses’

‘for it is not self-evident that it is the same object which is being determined thought of in different ways’


Frege, 1892[1993] p. 44

What are senses? Answer 1

I’ll give you three answers ...

Contrast that utterance of ‘Charly is Charly’ with the utterance ‘Charly is Samantha’

ftbe: These may differ in informativeness.

idea: This difference is due to some difference in the meanings of the words ‘Charly’ and ‘Samantha’.

Terminology: call whatever attribute of words explains the difference ‘sense’.

observation: There could be no such difference if meaning were reference.

conclusion: Sense and reference are distinct.

What is the meaning of ‘Earth’?

Simple idea: ‘Earth’ means Earth.

The meaning of a word is the thing it refers to.

Q2. Is there anything meanings are needed to explain which we cannot explain if we take this view of them?

Yes! Frege’s puzzle about Charly/Samantha (=Superman/Clarke Kent).

Complex idea: The meaning of a word is its sense.

What are senses? Answer 2

This is offered as an intuitive gesture towards an answer ...

‘Frege’s idea was that to understand an expression, one must not merely think of the reference that it is the reference, but that one must, in so thinking, think of the reference in a particular way.

The way in which one must think of the reference of an expression in order to understand it is that expression’s sense’


Evans, 1981 [1985]: 294

What are senses? (Answer 2)

The sense of a word is ‘the way in which one must think of the reference of [it] in order to understand it’.

What are senses? Answer 3

I’ll give you two answers ...

Andrea is in her office speaking on the telephone to her friend Ben. As she looks out of the window, Andrea notices a man on the street below using his mobile phone. He’s not looking where he’s going; he’s about to step out in front of a bus. Andrea does not realise that this man is Ben, the friend she is speaking to. She bangs the window and waves frantically in an attempt to warn the man, but says nothing into the phone.

\citep[adapted from][p.~439]{Richard:1983rl}

adapted from Richard, 1983 p. 439

He [‘the man on the street’] is in danger.

∴ He [‘the man I am speaking with’] is in danger.

valid-1 = the premises cannot be true unless the conclusion is true

valid-2 = knowledge of the premises suffices for knowledge of the conclusion

Since the man on the street is the man Andrea is speaking with, this inference is valid-1 but not valid-2.

[Answer 3] Sense is that which determines whether
such inferences are valid-2
(Campbell, 1992).

‘Sense is that, sameness of which makes trading on identity legitimate, difference in which means that trading on identity is not legitimate’ (legitimate: that is, knowledge of the premises suffices for knowledge of the conclusion) \citep[p.~59]{Campbell:1997tk}.