Causal Theories

1. Causal Theories

2. The absurdity of fit

3. The Absurdity of Fit In one sense, all the views we’ve considered in class so far are views on which meaning is a type of “fit.” On the idea theory, meanings (connotations) are ideas. Ideas have a certain pre-existing structure: just as in a painting the different parts are related to one another, and colored in various ways, and so forth.

4. Idea Theory and Fit In order to find out what an idea represents, we go out and find the things that best fit the idea, that most closely match its pre-existing structure, that best resemble it. Whatever best fits the pre-existing structure is what the idea represents.

5. Verificationism and Fit While verificationism doesn’t have the same “little colored pictures” view of ideas or the resemblance theory of representation, it too involves a type of fit. In advance, words are associated with specific experiences that are stipulated to verify them. Why does a certain experience verify “That is red”? Because we said so, that’s why. We say in advance what experiences verify which sentences, then we go look and see what experiences we have.

6. Definitions and Fit Similarly, a definitions view is a type of fit as well. We say in advance what the definitions of words are. You don’t discover that bachelors are unmarried, you sit down and make it true by fiat.

7. The Absurdity of Fit But there’s something terribly wrong with the idea that meanings are specified in advance of our encounters with the world. That before any experience of the world, we sit down and draw up a structural description, or a set of experiences, or a verbal description and say “whatever I find that’s like this, I will call ‘a dog’!”

8. The Paradox of Inquiry The worry here is that on any of these models, you can’t be radically wrong. If ‘gold’ is true of what most closely resembles your idea of gold, then most of your beliefs about gold must be true. And the same goes for most of your beliefs about anything. If representation is what fits best with what you’ve drawn up in advance, in advance of inquiry, you can be pretty sure you already know what’s true and what isn’t.

9. The Paradox of Inquiry In fact, this problem is as old as Plato, and it’s called “the paradox of inquiry.” The paradox is: suppose you want to know, say, the nature of lightning. If you know what lightning is in advance, then you don’t need to investigate, because that’s what you wanted to know. But if you don’t know, how do you know when you discover it, that lightning is X? You find X, but you don’t know that it’s lightning, because you don’t know what lightning is!

10. Causal Theories Causal theories of meaning are radically different from the “fit” views we’ve been considering. They say (roughly) that a word or a concept represents what causes you to say it or think it. So even if all your beliefs about gold, and all your utterances concerning gold are completely false, those thoughts/ sentences still represent gold so long as gold is responsible for you believing/ saying them.

11. Causation in philosophy

12. A classic problem in philosophy since before Socrates is: “What is knowledge?” What’s the difference between believing something and knowing it? A little reflection tells us that if you know something, then it has to be true. So maybe knowledge = true belief.

13. Socrates/ Plato vs. K = TB Suppose there has been a murder, and no eye-witnesses Suppose the jury is superstitious, and I convince them that X is guilty, b/c I dreamed that he was. No one is inclined to say that the jury knows that X is the killer. But if I was accidentally right, they will have a true belief that X is the killer.

14. True Beliefs, Bad Reasons Here the important point is that a belief that is true, but which you believe for bad reasons, is not really knowledge. If you believe something because you want to, or because your horoscope says it, or because a really unreliable person told it to you, then you don’t know it.

15. K = JTB This naturally suggests that for a belief to be knowledge, it not only has to be true, but has to be held for a good reason. This is the classic “JTB” account: knowledge = justified true belief. The reason the jury doesn’t know X is the killer is that Michael dreaming that X is guilty doesn’t justify anyone in believing that X is guilty (even if it’s true that they are guilty).

16. Gettier Cases However, in the hyper-classic 1963 paper “Is Knowledge Justified True Belief?” Edmund Gettier provides reasons for thinking K ≠ JTB. Here’s an example of a “Gettier case.”

17. Justification I’m at your house and I notice an iphone 5, a receipt for the purchase of an iphone 5 with your name on it, and a letter to your grandmother in your handwriting with the words “Dear Grandma, I just got an iphone 5” on it. I conclude justifiedly that you own an iphone 5.

18. Props However, suppose that the phone, the receipt, and the letter were just props for a movie you were making. (The next scene in the movie involves all of the props being smashed, and you wanted to convey how disappointed the character [who happens to have your same name] would be.) However, you really do own an iphone 5: it’s in your pocket where I can’t see it.

19. The Causal Account of Knowledge In this case I have a JTB that you have an iphone 5, but intuitively I don’t know that you do. What’s going on here? Well, some philosophers (e.g. Dretske 1981) think that this shows knowledge isn’t justified true belief, it’s true belief that’s caused by the fact the belief is about. My belief that you have an iphone 5 is not caused by your iphone 5, it’s caused by a prop. So I don’t know.

20. Right Direction The causal account has its problems (can’t we know things about the future even though causation doesn’t go from future to past?), but to many it seemed like the right direction. To know something is to have your beliefs based on the facts, where “based on” is some sort of causal notion.

21. The Success of Causal Theories • Knowledge (Dretske): X knows proposition P = the information that P causes X to believe P. • Action (Goldman): X performs action A = X’s beliefs and desires cause A. • Perception (Grice): X perceives object O = O causes an experience in X. • Representation?

22. Causation and representation

23. Motivations But why think that causation has anything to do with representation?

24. Greater Determinacy Imagine you’re in a mirror universe (or an eternal recurrence universe). You look at a table, and have a thought about it. You say “that’s a nice table.” Someone just like you in the other half of the “mirror” is having exactly similar experiences and saying exactly the same words. Why are your thoughts and your words about the table in front of you? Proposal: because that table is the one that caused your thoughts and your words, not the other table.

25. Fit is Inappropriate My experience of red represents a certain reflectance property of surfaces (reflects wavelengths between 630 and 700nm). But my experience in no way resembles that reflectance property any more than it resembles the reflectance property blue surfaces have (450 to 495nm). So why does my experience of redness represent the reflectance property it does? Because that’s the property that causes the experience.

26. Causation has the Right Structure?

27. Structure Notice importantly that cases that show representation is non-reflexive rather than irreflexive, and asymmetric rather than antisymmetric include the semantic paradoxes: • This sentence is false. • Sentence #3 is false. • Sentence #2 is true.

28. Possibility of Radical Error One of the most promising aspects of a causal theory of meaning is that it can allow for the possibility of radical error. If “atom” means whatever it is that causes me to use the word “atom,” then it’s possible that all my beliefs about atoms (that they have determinate locations and momenta, they’re point-like, they behave only like particles, etc.) might be false and yet “atom” still means atom.

29. Coordination across Theories A related upshot is that two people with radically different theories can nevertheless be talking about the same thing, and hence be meaningfully disagreeing with one another. I might think “abortion is the morally wrong thing that kills babies” and you might think “abortion is the morally acceptable thing that destroys a handful of cells.”

30. Coordination across Theories We can’t be talking about the same thing on a “fit” view. Nothing is both morally right and morally wrong. However, on a causal view, since abortions both cause me to apply the word “abortion” and cause you to do so, we’re talking about the same thing, and meaningfully disagreeing about it. It’s just that one of us is radically wrong.

31. The causal-historical account

32. Background Kripke’s causal-historical account is developed in his groundbreaking Naming and Necessity. The background is that he’s arguing against views on which the meanings of names (hence the first half of the title) are descriptions or definitions. This was a popular empiricist/ Russellian/ logical positivist view: the meaning of ‘Michael’ for example was constructed from basic sensations/ universals/ protocol sentences.

33. Against Descriptivism Kripke argues that for any name N, there is no description D that we associate with N such that: • If x satisfies the description, N = x. • If N = x, then x must satisfy the description.

34. Ignorance & Error He argues against each claim as follows: Against #1: Arguments from ignorance. Sometimes lots of things satisfy the descriptions we associate with N, but only one is N. Against #2: Arguments from Error. Sometimes nothing satisfies the descriptions we associate with N (or some non-x does), but N still = x.

35. Ignorance: Feynman Kripke’s first argument is this. Lots of people sensibly talk about Richard Feynman. If asked “What is everything you know about Feynman?” they might reply “He’s a physicist, he’s famous, he’s dead, and he worked on quantum mechanics.” Lots of people satisfy that description (Bohr, for example). But it’s not true that ‘Feynman’ means Bohr and it’s not true that it means nothing. How is that possible for the descriptivist?

36. Error: Einstein Kripke’s second argument goes like this. Lots of people (this is back in 1970 when Kripke was writing) know almost nothing about Einstein. If asked “What is everything you know?” they might respond, “Einstein invented the nuclear bomb.” But “the inventor of the nuclear bomb” can’t be the meaning of ‘Einstein’ because then ‘Einstein’ would refer to Leo Szilard (or whoever).

37. Kripke’s Picture “Someone, let’s say, a baby, is born; 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 elsewhere, 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.”

38. Kripke’s Picture “A rough statement of a theory might be the following: An initial ‘baptism’ takes place. Here the object may be named by ostension, or the reference of the name may be fixed by a description. When the name is ‘passed from link to link’, the receiver of the name must, I think, intend when he learns it to use it with the same reference as the man from whom he heard it.”

39. Reference-Fixing Descriptions So Kripke’s idea is that descriptions may be used to initially latch on to or think about an individual (“this baby in front of me…”). However, what gives a name its meaning now is not any description or definition whatsoever. The name inherits its meaning from the people you got the name from. This means that everything you believe about Einstein could be false, and you can still think of Einstein.

40. Natural Kinds Kripke and another philosopher Hilary Putnam wanted to generalize what was true of names to “natural kind terms” (a phrase introduced by Quine). There’s no real consensus on what this class encompasses, but common examples include: fundamental particles (electrons), chemical substances (cesium), biological taxa (chimpanzees), natural phenomena (lightning), secondary qualities (heat).

41. Ignorance: Water In Hilary Putnam’s classic “The Meaning of ‘Meaning’” he argues that “meaning just ain’t in the head.” In particular, he presents his famous Twin Earth thought experiment, which is intended to show that what the word ‘water’ is true of is not determined by what we know or believe about water.

42. Twin Earth Twin Earth is a planet on the other side of the galaxy. In most ways, it is just like Earth, down to the smallest detail. You have a twin on Twin Earth who’s just like you, I have a twin who’s just like me, they’re sitting in a twin classroom, and my twin is giving a lecturejust like this one to your twin. And so on and so forth.

43. Earth Twin Earth

44. Twin Earth There is however one difference between Earth and Twin Earth. On Earth, all the watery stuff is H2O. On Twin Earth, the watery stuff is composed of a complicated chemical compound we can abbreviate XYZ. H2O and XYZ look and behave exactly the same. They taste the same, they boil at the same temperatures at the same distance above sea level, their conductance is the same, etc.

45. Twin Earth Consider two twins, Arnold on Earth and Twin Arnold on Twin Earth. Neither knows any chemistry. What they know/ believe about the stuff they call ‘water’ is the same. Q: Would it be true for Arnold to call the stuff on Twin Earth ‘water’?

46. Twin Earth The intuition is supposed to be that, no, Arnold’s word ‘water’ is true of all an only H2O, whereas Twin Arnold’s word ‘water’ is true of all and only XYZ

47. The Moral The conclusion Kripke and Putnam draw from such cases is that we fix the referent of ‘water’ by a description like “the stuff around here in lakes and rivers and streams that falls from the sky and quenches thirst.” But this description only fixes the referent. If you replaced all the H2O on Earth with XYZ, there wouldn’t be any more water here.

48. Error: Gold Neither Kripke nor Putnam present any real cases where, through error, our beliefs about X are completely false of X, yet “X” still means X (like the Einstein case). (There’s probably lots of cases in contemporary physics.) But Kripke presents some imagined ones. Kant thought that the definition of gold was ‘yellow metal.’ Kripke then asks, “Could we discover that gold was not in fact yellow?” p. 118.

49. Imagine Gold’s Not Yellow Kripke argues that we could. He asks us to suppose that something is weird about the air in places where gold is most prevalent. This strange air makes it appear that gold is yellow, but when we isolate gold in normal air, it’s obviously blue. Since this is clearly conceivable, it can’t be that gold means yellow metal, because if X means Y, then anything that is X is Y.

50. Error: Tigers Here’s a case from Paul Ziff in Semantic Analysis (referenced in Kripke p. 119 of 1980 edition). The Shorter OED has “the tiger is a large quadrupedal feline, tawny yellow in color, with blackish transverse stripes and a white belly.” Ziff argues that this can’t be what ‘tiger’ means, because if someone said “I just saw a three-legged tiger,” that wouldn’t be a contradiction.