Chomsky's Views on Linguistics and Cognitive Science

1. SEL2211: Contexts Lecture 10: Generative Grammar and Cognitive Science

2. Last time: • What linguistics is not • It’s not stimulus → response → reinforcement conditioning This time: • Chomsky on what linguistics is • Some familiar ideas, but with (mostly) different examples and with a focus on the themes of the course thus far

3. Chomsky on minds and bodies • Chomsky (1987): “A person who speaks a language has developed a certain system of knowledge, represented somehow in the mind and, ultimately, in the brain.” • So, talk about the mind is just talk about the brain at some level of abstraction that seems relevant for understanding certain things about it. • A favorite technique of Chomsky’s • Translate questions about ‘the mental’ into ‘the physical’

4. How would we study the human body? • There’s a respiratory system, a circulatory system, and a language system (from http://poster.4teachers.org/worksheet/view.php?id=140793&page=5)

5. Crucially, as discussed there’s no mind/body problem, just the usual issue: • Descriptions about different aspects of the world • one day these descriptions might be related, but this doesn’t necessarily entail that one description is/will/ought to be reduced to the other • Economics and psychology • = some relation, but there is no suggestion that economics is/will/ought to be reduced to psychology, or that there’s a grave philosophical problem if we don’t know how to do this now, today. • Cases like classical genetics  DNA are fresh in the mind, but actually very rare • Remember discussion of ‘levels’

6. So, to investigate the ‘language system’ of the human body: • Just try to find ‘the best theories’ • Only justification is do they or don’t they contribute to understanding • We don’t want to replace metaphysical dualism with methodological dualism

7. Linguistics as Cognitive Scienc • To recap, linguistic theory modules are theories of your mental representations • English phonology: pit vs spit

8. English syntax • The structure isn’t present in the acoustic signal, only in your mental representation of it

9. A note on ‘psychological reality’ • Are things like Binding Theory, or phonemes, ‘real’? Recall Chomsky’s heuristic – does the equivalent physical question make any sense? • Is mass ‘physically real’? Do things ‘really’ have mass? Or angular momentum? • NC sez – nobody would ask these questions because nobody’s confused about it • If the best theory of the world says that objects possess a property called ‘mass’, they just do. (Mass is not weight, btw) • So if the best theory of the world and its phenomena postulates “Binding Theory”, then Binding Theory exists.

10. Theories change, too, but that’s not a problem • ‘Ether’ used to exist, now it doesn’t anymore.

11. Chomsky’s Four Questions (Chomsky 1987) Question 1:What is the system of knowledge? Question 2: How does the system of knowledge arise? Question 3: How is the system of knowledge put to use? Question 4: What are the physical mechanisms that underlie the system of knowledge?

12. Questions 1 and 2 • Question 1: What is this system of knowledge? In other words, what is in the mind/brain of the speaker of English or Japanese? What are the mental representations and what are the algorithms that create and operate on them? • This is basically the question that’s examined in modules that you’re taking in syntax, phonology, semantics and pragmatics, etc. • Question 2: How does this system of knowledge arise in the mind/brain? This is the question which is taken up largely in modules on language acquisition, though the question also arises in a more general/abstract way (sometimes explicitly, sometimes implicitly) in other modules.

13. These questions are intimately related • “How is X acquired?” requires at least some account of what X is. • Many problems over the centuries caused by failure to appreciate how complicated Question 1 is

14. For example, Bloomfield (1933) – a behaviorist approach to language His account of language acquisition • Child starts by babbling – acquiring the habit of associating particular mouth movements with particular sounds striking his/her ear. • Child sees that caregiver utters sound which is similar to one of the babbling syllables, say “doll”, which is similar to “da”. • Child notices that caregiver says “doll” when he/she is showing or giving the doll to child, thus creating new habit – saying “da” in presence of doll. • Child moves onto “displaced” speech, saying “da” when doll is not present because child wants or is asking for doll. • Child eventually through selective reinforcement moves to ever more correct imitations, moving from saying “da” to “doll” because eventually child doesn’t get doll when just “da” is produced. • Even if possibly plausible for acquisition of word pronunciation, doesn’t work for, e.g., word meaning

15. In other words, language acquisition faces Plato’s Problem A semantics example (just to do something different) • Between 7 and 16, children learn about 10 words per day • Can’t be learning these on more than a handful of exposures, yet they have extraordinarily complex properties

16. “House” (Chomsky 1995) • If I say “I painted my house brown”, default interpretation = “brown on the outside” • But this can be overridden – “I painted my house brown on the inside” • If I’m ‘near’ my house, that means ‘near to an exterior surface’ • But that can’t be overridden – I’m not ‘near’ my house if I’m inside it. • If I’m in my house, I can clean it, but I can’t see it (unless there’s a mirror across the street) • If a house is vaporized, and rebuilt with different materials on a site 10 miles away, it’s not “the same house” – but ‘city’ works differently

17. How do we know all this?!?!?? • Plato’s answer: reincarnation • Chomsky’s answer: genetics • Chomsky, btw, is here overtly allying himself with the rationalist tradition in philosophy • parts of are knowledge are derived “from the original hand of nature” and are “a species of instinct” (David Hume) • Rationalism contrasts with empiricism (from the last lecture)

18. Question 3 • How is the knowledge that we possess put to use? • Breaks down into two questions: the perception and the production problems. • Clearly we put the system of knowledge to use in understanding what we hear. That’s the perception problem. This problem looks straightforward, if hard. • The production problem, on the other hand, is more obscure. • Seems to involve free will/the creative aspect of language use

19. As Chomsky notes, Questions 1 and 3 have often been confused • Common in disciplines outside linguistics (e.g., philosophy of psychology) not to distinguish language knowledge from language use • However, there is a distinction to be made • Great poets have same knowledge as you and me, but can ‘use’ the language better (in some sense) • Certain head injuries can take away ability to speak/understand a language temporarily

20. Question 4 • What are physical mechanisms that underlie knowledge of language? • Very new enterprise • Two points to bear in mind • (1) simply because we’re not in a position to give a definitive answer doesn’t mean that we can’t begin to look into the question; however • (2) we can’t be dogmatic about how we proceed.

21. A favorite example (discussed by Chomsky) – 19th century chemistry 1869 – the periodic table of the elements (Dimitri Mendeleev)

22. Periodic table ignited a controversy – was it ‘real’? • The anti side: crucial concepts like ‘atomic number’, ‘atomic weight’ and ‘valence’ don’t correspond to any known concept of physics. It can only be a calculating device, not anything real • The pro side: The classification/organization does reflect reality, but in some way that isn’t yet understood.

23. We now know the answer: the pro side was right. The physics of the time was radically wrong Atoms in the 19th century: Atoms in the 20th century:

24. So, what do we learn from this? • Let’s just investigate the world along various tracks and not to be overly worried if it’s not clear how ‘higher’ levels relate to ‘lower’ levels, as we currently understand them. • It may be that one day we can see how large parts of one approach may directly relate to another one (in the way that biochemistry unifies parts of biology with parts of chemistry), but also that may not happen (or even be the right thing to do) (as in the relation between economics and psychology).

25. We’ve talked about neurons, and that looks plausible, but could easily be wrong • Event Related Potentials • changes in the brain’s electrical activity as a response to certain stimuli (e.g., thoughts, perceptions, etc.) Some research to suggest that one particular change (N400) is associated with semantic deviance (e.g., ‘John hit sincerity.)

26. So, for Chomsky • language is something mental, but this does not carry any philosophical baggage. (In fact, it’s precisely behavior, in the sense of why we produce the particular utterances we do, which Chomsky suggests is deeply problematic.) • Talk about mental events and properties is just talk about the brain at some slightly more abstract level. • This view is justified to the extent that it helps us develop insightful theories about the phenomena under discussion, but is subject to all the same qualifications that ordinary scientific inquiry is subject to (revision, underdetermination, etc.)

27. Next Time What does this all mean for, e.g., sociolinguistics and historical linguistics?