1. The Causal Theory of Reference

2. Explaining Reference Kripke: a name refers to a thing if there is the right sort of causal link between the thing and the use of the name Kripke: a name refers to a thing if there is the right sort of causal link between the thing and the use of the name This causal link is equivalent to Frege’s sense This causal link is equivalent to Frege’s sense It is explicable in purely physicalist terms It is explicable in purely physicalist terms

3. Baptism The event that fixes the reference of a term is a baptism or dubbing The event that fixes the reference of a term is a baptism or dubbing Point at dog and say ‘this is Fido’ Point at dog and say ‘this is Fido’ Establishes a causal link between term and thing Establishes a causal link between term and thing Causal link exists for all witnesses of this act Causal link exists for all witnesses of this act

4. Borrowing Those who don’t witness baptism have to ‘borrow’ reference Those who don’t witness baptism have to ‘borrow’ reference They are causally linked to other users who have the referencing ability They are causally linked to other users who have the referencing ability Ultimately all referencing depends on causal connections to witnesses of the baptism Ultimately all referencing depends on causal connections to witnesses of the baptism We can talk about Napoleon because we are causally connected in the right way to someone who saw Napoleon, and to the one who named him. We can talk about Napoleon because we are causally connected in the right way to someone who saw Napoleon, and to the one who named him.

5. Advantages It explains Frege’s notion of ‘sense’ It explains Frege’s notion of ‘sense’ The sense of ‘Venus’ is different from the sense of ‘Phosphorus’ because the causal chain that links Venus to ‘Venus’ is different from that which links Venus to ‘Phosphorus’ The sense of ‘Venus’ is different from the sense of ‘Phosphorus’ because the causal chain that links Venus to ‘Venus’ is different from that which links Venus to ‘Phosphorus’

6. Advantages It explains Frege’s notion of ‘sense’ It explains Frege’s notion of ‘sense’ Sense determines reference, and the causal chain determines reference by being linked to the relevant thing Sense determines reference, and the causal chain determines reference by being linked to the relevant thing

7. Advantages It explains Frege’s notion of ‘sense’ It explains Frege’s notion of ‘sense’ To understand the meaning of a word is to grasp the sense To understand the meaning of a word is to grasp the sense The causal chain from use of a term to the thing itself must pass through the brain The causal chain from use of a term to the thing itself must pass through the brain It depends on some causal features in the brain It depends on some causal features in the brain Which is why not all brains can have the right causal links Which is why not all brains can have the right causal links Animals, for example Animals, for example Those causal features are the grasping of the sense Those causal features are the grasping of the sense

8. Advantages Solves the ‘puzzles’ of reference Solves the ‘puzzles’ of reference How do Venus is the evening star Venus is Venus have different meanings though their referents are identical? How do Venus is the evening star Venus is Venus have different meanings though their referents are identical? Because the meanings are constructed out of senses and the senses/causal links are different for ‘Venus’ and the ‘evening star’ Because the meanings are constructed out of senses and the senses/causal links are different for ‘Venus’ and the ‘evening star’

9. Advantages Solves the ‘puzzles’ of reference Solves the ‘puzzles’ of reference How can we talk about things that don’t exist? How can we talk about things that don’t exist? There can’t be causal links to non-existent things There can’t be causal links to non-existent things Consider how the name ‘Pegasus’ is introduced Consider how the name ‘Pegasus’ is introduced Described as a horse with wings Described as a horse with wings The terms ‘horse’ and ‘wing’ both refer The terms ‘horse’ and ‘wing’ both refer Those terms have causal chains Those terms have causal chains Therefore ‘Pegasus’ has a causal chain Therefore ‘Pegasus’ has a causal chain

10. Advantages Solves the ‘puzzles’ of reference Solves the ‘puzzles’ of reference How can we say that things don’t exist? How can we say that things don’t exist? There can’t be causal links to non-existent things There can’t be causal links to non-existent things The ‘Pegasus’ solution works here too The ‘Pegasus’ solution works here too

11. Problems Change of reference Change of reference 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.

12. Problems Change of reference Change of reference There are multiple chains between terms and referents There are multiple chains between terms and referents Every introduction forms another chain from Bob to ‘Bob’ Every introduction forms another chain from Bob to ‘Bob’ Some may link the referent and different terms, Others may link the same term to different referents Some may link the referent and different terms, Others may link the same term to different referents If too many link a referent and a different term then that term becomes the name of the object If too many link a referent and a different term then that term becomes the name of the object

13. Problems -problem Quâ-problem I point at a dog and say ‘Fido’ I point at a dog and say ‘Fido’ Why have I named the particular dog and not the species, or the dog’s nose, or an air molecule at the end of my finger, or the idea of the dog, or … Why have I named the particular dog and not the species, or the dog’s nose, or an air molecule at the end of my finger, or the idea of the dog, or … It’s the intention of the grounder to name the dog It’s the intention of the grounder to name the dog The intention must be a describable one The intention must be a describable one So descriptions are again required So descriptions are again required

14. Problems Natural kind terms Natural kind terms The solution to the quâ-problem requires descriptions of natural kind terms The solution to the quâ-problem requires descriptions of natural kind terms They have all the same problems as in pure description theories They have all the same problems as in pure description theories Modal Problem Modal Problem “Tigers are wild striped felines” “Tigers are wild striped felines” There’s a possible world where they don’t have stripes There’s a possible world where they don’t have stripes Because there are no Freemasons Because there are no Freemasons They are still tigers They are still tigers

15. Problems Natural kind terms Natural kind terms The solution to the quâ-problem requires descriptions of natural kind terms The solution to the quâ-problem requires descriptions of natural kind terms They have all the same problems as in pure description theories They have all the same problems as in pure description theories Necessity Problem Necessity Problem You don’t need to be able to describe an elm in order to be able to refer to it You don’t need to be able to describe an elm in order to be able to refer to it

16. Problems Natural kind terms Natural kind terms The solution to the quâ-problem requires descriptions of natural kind terms The solution to the quâ-problem requires descriptions of natural kind terms They have all the same problems as in pure description theories They have all the same problems as in pure description theories Sufficiency Problem Sufficiency Problem Pegasus is the winged horse Pegasus is the winged horse But if we find a winged horse created by Freemasons in Tibet by gene-splicing, that wouldn’t be Pegasus But if we find a winged horse created by Freemasons in Tibet by gene-splicing, that wouldn’t be Pegasus

17. Problems Twin-Earth is a planet just like Earth except water there is not H 2 O, but XYZ Twin-Earth is a planet just like Earth except water there is not H 2 O, but XYZ ‘Water’ as said by a twin-Earthling does not mean the same as ‘water’ said by an Earthling ‘Water’ as said by a twin-Earthling does not mean the same as ‘water’ said by an Earthling Yet everything is the same. Yet everything is the same. Descriptions can’t give the meanings of terms Descriptions can’t give the meanings of terms Meanings just ‘ain’t in the head’ Meanings just ‘ain’t in the head’