Meanings as Instructions for how to Build Concepts

Meanings as Instructions for how to Build Concepts Paul M. Pietroski University of Maryland Dept. of Linguistics, Dept. of Philosophy http://www.terpconnect.umd.edu/~pietro

Tim Hunter Darko Odic Jeff Lidz Justin Halberda not pictured: Norbert Hornstein

Advertisements • Some basic questions about words, word meanings, and how they combine • A general proposal about what word meanings are, how they combine, and how they relate to psychology • A detailed case study of how to bring experimental methods to bear on rather abstract theoretical questions

Advertisements • Some basic questions about words, word meanings, and how they combine • A general proposal about what word meanings are, how they combine, and how they relate to psychology • A detailed case study of how to bring experimental methods to bear on rather abstract theoretical questions • General Perspective: the questions are better than my answers • I study linguistic meaning because of what it reveals about human nature…not because I’m really interested in communication, languages, metaphysics, reference, truth, …

One of Aristotle’s Observations Some animals are born early, and take time to grow into their “second nature”

Catterpillars become Butterflies, Humans acquire Languages Infant Child Modules: Vision Audition … Modules: Vision Audition … Language Acquisition Device in a Mature State: GRAMMAR LEXICON Language Acquisition Device in its Initial State Experience and Growth

Humans acquire Words and Grammars • Dramatic change in a critical period, early in the life cycle • Large components of this change might well be viewed as “evicted embryology” (or a kind of pupal stage) that allows for environmental influence • Of course, infants also acquire concepts in the critical period • Hard to see how one could acquire words, as opposed to meaningless sounds (or signs), without acquiring concepts • Indeed, one might think that words pair sounds with concepts

Infant Child Modules: Vision Audition … Modules: Vision Audition … Language Acquisition Device in a Mature State: GRAMMAR LEXICON Language Acquisition Device in its Initial State Experience and Growth initial concepts initial concepts acquired concepts

Humans acquire words, concepts, and grammars • What are words? • What are concepts? • What are grammars?

Humans acquire words, concepts, and grammars • What are words? • What are concepts? • What are grammars? • How are words related to concepts and grammars? • How are words, concepts, and grammars related • to whatever makes humans distinctive, • linguistically and cognitively?

Lexicalization: capacity to acquire words Combination: capacity to combine words Lexicalization and Combination (iv)Distinctive concepts that get paired with signals (v) Something else entirely What makes humans linguistically special?

Lexicalization: capacity to acquire words Combination: capacity to combine words Lexicalization and Combination (iv)Distinctive concepts that get paired with signals What makes humans linguistically special?

Lexicalization: capacity to acquire words Combination: capacity to combine words (iv)Distinctive concepts that get paired with signals What makes humans linguistically special?

Lexicalization: capacity to acquire words Combination: capacity to combine words (iv)Distinctive concepts that get paired with signals FACT: kids are the best lexicalizers on the planet What makes humans linguistically special?

Lexicalization: capacity to acquire words FACT: kids are the best lexicalizers on the planet What makes humans linguistically special?

Idea (to be explained and defended) • In acquiring words, we use available concepts to introduce new ones • 'ride' + RIDE(x1, x2) ==> RIDE(_) + 'ride' + RIDE(x1, x2) • Words are then used to fetch the introduced concepts • when you hear the word ‘ride’…..fetch the concept RIDE(_) • The new concepts can be systematically conjoined • 'ride fast' RIDE(_) & FAST(_) • 'ride horses’ RIDE(_) & [THEME(_, _) & HORSES(_)] • 'ride horses fast’ RIDE(_) & [THEME(_, _) & HORSES(_)] & FAST(_) • ‘ride fast horses’ RIDE(_) & [THEME(_, _) & FAST(_) & HORSES(_)]

Humans acquire words, concepts, and grammars • What are words, concepts, and grammars? How are they related? • How are they related to whatever makes humans distinctive? • Did a relatively small change in our ancestors lead to both the • "linguistic metamorphosis” that human infants undergo, and • significant cognitive differences between us and other primates?

Humans acquire words, concepts, and grammars • What are words, concepts, and grammars? How are they related? • How are they related to whatever makes humans distinctive? • Did a relatively small change in our ancestors lead to both the • "linguistic metamorphosis” that human infants undergo, and • significant cognitive differences between us and other primates? • Maybe… • we’re cognitively special because we’re linguistically special, and • we’re linguistically special because we acquire words, and • acquiring words is a cognitively creative process, but • grammars are simple (or “Minimal” in Chomsky’s sense)

Humans Acquire... Words • can combine grammatically to form phrases and sentences 'horse', 'brown', 'brown horse', 'horses', 'ride', 'ride horses', 'every’, ‘every horse’, ‘ride every horse’, ‘We saw them ride every brown horse’, … • can be understood and used (externally and internally) • seem to be distinctively human, although there are many animal communication systems

Humans Acquire... Concepts • can combine to form complex concepts and thoughts HORSE, BROWN, BROWN_HORSE, HORSES, RIDE, RIDE_HORSES, EVERY, EVERY_HORSE, RIDE_EVERY_HORSE, WE_SAW_THEM_RIDE_EVERY_BROWN_HORSE, … • can be used to think about things • seem not to be distinctively human, although there are many distinctively human concepts

Humans Acquire... Grammars • can be used to combine words into phrases and sentences • can be used to understand phrases and sentences, in terms of the component words • human grammars seem to be distinctively human • but other animals surely use various procedures to combine concepts into thoughts (see Fodor, Gallistel)

Humans acquire words, concepts, and grammars What are words? What are concepts? What are grammars? How are words related to concepts and grammars? How are words, concepts, and grammars related to whatever makes humans distinctive, linguistically and cognitively? How are human grammars related to older animal procedures for combining concepts?

Concepts:Composable Mental Representations Two Common Metaphors Jigsaw Puzzles 7th Grade Chemistry -2 +1H–O–H+1

Jigsaw Metaphor one Dyadic Concept (adicity: -2) “filled by” two Saturaters (adicity +1) yields a complete Thought A THOUGHT Sang( ) Brutus Unsaturated Saturater second saturater KICK(1, 2) one Monadic Concept (adicity: -1) “filled by” one Saturater (adicity +1) yields a complete Thought first saturater Doubly Un- saturated Caesar Brutus

7th Grade Chemistry Metaphor a molecule of water -2 +1H(OH+1)-1 a single atom with valence -2 can combine with two atoms of valence +1 to form a stable molecule

7th Grade Chemistry Metaphor -2 +1Brutus(KickCaesar+1)-1

7th Grade Chemistry Metaphor +1BrutusSang-1 +1NaCl-1 an atom with valence -1 can combine with an atom of valence +1 to form a stable molecule

Extending the Metaphor Aggie Aggie Cow( ) Brown( ) +1 +1 -1 -1 Aggie is brown Aggie is (a) cow BrownCow( ) Aggie Aggie is (a) brown cow Brown( ) & Cow( )

Extending the Metaphor Aggie Aggie Cow( ) Brown( ) +1 +1 -1 -1 Conjoining two monadic (-1) concepts can yield a complex monadic (-1) concept Aggie Brown( ) & Cow( )

Grammars:Procedures for Combining Words • Church: function-in-intension vs. function-in-extension --a procedure that pairs inputs with outputs in a certain way --a set of input-output pairs • Frege: each Function determines a "Course of Values” • Chomsky: I-language vs. E-language --a biologically implementable procedure that pairs phonological structures (PHONs) with semantic structures (SEMs) --a set of <PHON, SEM> pairs

I-Language/E-Language function in Intensionimplementable procedure that pairs inputs with outputs function in Extension set of input-output pairs |x – 1| +√(x2 – 2x + 1) {…(-2, 3), (-1, -2), (0, 1), (1, 0), (2, 1), …} λx . |x – 1| = λx . +√(x2 – 2x + 1) λx . |x – 1| ≠ λx . +√(x2 – 2x + 1) Extension[λx . |x – 1|] = Extension[λx . +√(x2 – 2x + 1)]

PHONs   Language Acquisition Device in a Mature State (an I-Language): GRAMMAR LEXICON Language Acquisition Device in its Initial State Experience and Growth SEMs  

 Articulation and Perception of Signals PHONs   Language Acquisition Device in a Mature State (an I-Language): GRAMMAR LEXICON Language Acquisition Device in its Initial State Experience and Growth initial concepts   SEMs   initial concepts acquired concepts

It seems that concepts must predate words Old idea: words label concepts • Acquiring words is basically a process of pairing concepts with perceptible signals • Word combination should mirror concept combination • Sentence structure should mirror thought structure

Further lexical information Concept of adicity n Concept of adicity n Perceptible Signal Word: adicity n KICKED(1, 2) ‘Brutus kicked Caesar’ ‘Brutus kicked Caesar the ball’ ‘Caesar was kicked’ ‘Brutus kicked’ ‘Caesar got a kick’ But what about…

Puzzles for the idea thatWords simply Label Concepts • Apparent mismatches between how words combine (grammatical form) and how concepts combine (logical form) KICK(x1, x2) The baby kicked RIDE(x1, x2) Can you give me a ride? BEWTEEN(x1, x2, x3) I am between him and her BIGGER(x1, x2) That is bigger than that FATHER(…?...) Fathers father MORTAL(…?...) Socrates is mortal A mortal wound is fatal

Puzzles for the idea thatWords simply Label Concepts • Apparent mismatches between how words combine (grammatical form) and how concepts combine (logical form) BEWTEEN(x1, x2, x3) I am between him and her why not: Between I him her BIGGER(x1, x2) This is bigger than that why not: This bigs that

Puzzles for the idea thatWords simply Label Concepts • Apparent mismatches between how words combine (grammatical form) and how concepts combine (logical form) x2:HORSE(x2)[RODE(Peter, x2)] Peter rode every horse why not: Every horse rode Peter or: Every horse Peter rode That dog is a poodle That dog is a father That dog is brownThat dog is yours That dog is a brown poodle That dog is (a) your father

Puzzles for the simple idea thatWords simply Label Concepts • Apparent mismatches between how words combine (grammatical form) and how concepts combine (logical form) • Humans are special linguistically AND cognitively • Why bother with human syntax (nouns, verbs, prepositions, classifiers, ...)? Why not just pair concepts with signals, and pronounce logical forms "straight"? • If the labeled concepts can combine without the words, why create the problem of mapping covert expressions into formally distinct overt expressions?

It seems that concepts must predate words A less old idea: words help thinkers use available concepts to introduce new ones • Acquiring words is a formally creative process • Grammatical structure may not reflect initial conceptual structure

Lexicalization as Concept-Abstraction Concept of adicity n Concept of adicity n Perceptible Signal (initial concept) Concept of adicity k

Two Pictures of Lexicalization Further lexical information Concept of adicity n Perceptible Signal Concept of adicity n Word: adicity n further lexical information Concept of adicity n Perceptible Signal Word: adicity k (initial concept) Concept of adicityk

Lexicalization as Monadic-Concept-Abstraction KICK(x1, x2) KICK(event) Concept of adicity n Concept of adicity n Perceptible Signal Word: adicity -1 (before) Concept of adicity -1

 Articulation and Perception of Signals PHONs   Language Acquisition Device in a Mature State (an I-Language): GRAMMAR LEXICON Language Acquisition Device in its Initial State Experience and Growth initial concepts   SEMs   initial concepts acquired concepts

 Articulation and Perception of Signals PHONs   Language Acquisition Device in a Mature State (an I-Language): GRAMMAR LEXICON Language Acquisition Device in its Initial State Experience and Growth initial concepts   SEMs   introduced concepts other acquired------> concepts initial concepts

Meanings as Instructions for how to Build Concepts