Protolanguage: Between Holophrastic and Atomic Meanings

1. Protolanguage: Between Holophrastic and Atomic Meanings Mike Dowman University of Tokyo January 23, 2007

2. Protolanguage • At some time in the past humans didn’t have language. • What did the first human languages look like? • Were there simple languages before complex ones?

3. Starting Small • The first humans could only articulate and/or perceive a limited number of distinct words • No phonology • Little or no syntax • They only tried to convey a limited number of simple meanings

4. Bickerton (1990, 1996) • Words in the first languages were like modern words • Labeled preexisting concepts and entities • Words used in short strings • No fixed word order • Words can be omitted

5. Modern Day Examples of Protolanguage • Children under two • Speakers of pidgins • Adults deprived of language in childhood • Trained apes: Nim eat Nim eat Tickle me Nim play Me banana you banana me you give Banana me me me eat

6. Wray (1998) • The First Words in Protolanguages were Holophrastic • Each word conveyed a whole complex meaning (e.g. Give me the meat) • Chimpanzee vocal noises and gestures are holistic • Inform about location of food, threaten, get another chimpanzee to do something

7. Syntactic Abilities • Word categories • Permissible and ungrammatical sequences • Mapping from structures to meanings • Breaking meanings into bits • Making sure all the bits are expressed once • No bits are expressed more than once

8. The Agents have none of these Syntactic Abilities Can only associate words and meanings • Can’t associate part of a meaning with part of an utterance • When speaking just choose the word(s) that seem to be most appropriate given the whole proposition to be expressed The model is therefore of protolanguage only • Not the transition to syntax

9. The Iterated Learning Model • One agent per generation • Each agent sees meanings and hears words produced by the agent in the previous generation • Agents’ knowledge of language is just a list of meanings they’ve heard each word used to express

10. Nature of Utterances • Each utterance consisted of only a single word • Agents could use only a small number of words (limited communicative capacity) • Available words fixed throughout each simulation

11. Meaning Representations • Small number of semantic primitives (limited conceptual capacity) • Each utterance would try to express a complex meaning represented by a group of three different primitives • hunt, pig,forest means ‘Hunt pigs in the forest’ • dog, pig, sleep means ‘Dogs and pigs are sleeping’

12. Agents’ Choice of Words • Agents use the word whose past uses have been most similar to the current meaning • If current meaning is: eat, house, pig • Previously heard used to express: eat, house, dog hunt, forest, pig Match = 4/9 hunt, forest, pig

13. Agents’ Choice of Words • If degree of match is one, agent will always use that word • Otherwise will use any available unused word (and the word-meaning pair remembered) • Otherwise pick highest degree of match (choosing at random in the event of a tie)

14. Simulations • Each meaning contained 3 elements from a set of 10 (so 120 distinct complex meanings) • Each agent produced 1000 utterances for the agent in the next generation (each expressing a randomly chosen meaning) • Simulations were run for ten generations • The number of available words was varied

15. Emergence of Words with Atomic Meanings • In the first simulation the agents could only use 10 distinct words • All the agents made use of all 10 available words • Most words were used only when one particular semantic element was present • Their meanings appear to correspond to those elements

16. Example Atomic Type Words The words are like modern nouns or verbs

17. Emergence of Holophrastic Words • In the next simulation the agents could use 150 distinct words • All agents used 120 of these words • Each word expresses a single complex meaning • These words are all holophrastic

18. Example Holophrastic Words

19. Emergence of Intermediate Types of Language • What happens when the number of available words is in between the number of semantic elements and the number of complex meanings? • Do we get a mixture of atomic and holophrastic words? • A new simulation with 50 available words tested this • All agents used all the available words

20. Language contains words with varying degrees of holophrasticity It’s intermediate between a protolanguage with atomic words and a holophrastic one

21. Varying Degrees of Holophrasticity • The frequency of each type of word depended on the number of distinct words available • With 50 words there were: 10 holophrastic words, 35 words containing two fixed semantic elements, 4 words containing one fixed element, and 1word containing no fixed elements at all • With a smaller number of distinct words, the languages become less holophrastic • With more available words they became more holophrastic

22. Fewer Words than Semantic Elements • What if the agents could not even produce one distinct word for each semantic element? • (Or alternatively what if they knew so many semantic elements they could use more than there were words?) • A new simulation was conducted with only 5 distinct words available

23. Emergent Words • Three words had one fixed semantic element • One word used any three of the other seven semantic elements • The final word contains at least two of the elements eat, gather and pig • This is a new type of word, and is partly holophrastic

24. Co-evolution of Agents and Protolanguages • What happens as agents communicative and conceptual capacities evolve phylogenetically? • We would expect the agents’ protolanguages to rapidly adapt to the agents new capacities • How will the degree of holophrasticity change over time?

25. Increasing Communicative Capacity • The first agents could use only a single word • After every 10 generations the number of words they could use was increased by 1 • Number of semantic elements fixed at 10 • 1300 generations simulated

27. Increasing Conceptual Complexity • In this simulation there were always 120 words available • Initially there were 10 semantic elements • After every 10 generations the number of available semantic elements was increased by 1 • This simulation was also run over 1300 generations (so there were 447,580 different complex meanings at the end of the simulation)

29. Transitions between Atomic and Holophrastic Words • The first simulation showed a progression from atomic words to holophrasis • The second from holophrasis to atomic words So depending on the relative rates of monotonic evolution of communicative and conceptual capacity we could see multiple swings between each type of protolanguage

30. Multiple Word Utterances Did the first protolanguage utterances contain single or multiple words? protolanguage gorillas humans chimps multi-word proto-languages

31. Multiple Word Utterances • Maximum length of utterances was fixed at 3 words • If agents knew a word whose past uses exactly matched the current meaning they used it (and nothing else) • Otherwise if a new word was available they used that (and remembered it) • Finally, if none of the above apply, the agents chose the 3 closest matches to the current meaning. Each of these words was then paired with the current meaning by the hearing agent

32. With 10 words, some express all or most meaning elements equally • Many fewer fully holophrastic words • More words with 2 common meanings than distinct 2 element combinations (45)

33. E-Language and I-Language • If we look at agents’ internal linguistic representations (I-Language) we only see an unanalyzed list of the past uses of a word • However, if we could only observe the agents’ speech (E-Language) and the meanings they tried to express we would (in some cases) be able to identify the words with specific semantic elements • So a categorization ability is not necessary for a language with categorical words to emerge

34. Are there Atomic Pre-Linguistic Concepts? • Isn’t boy a holophrase for young male human? • And eat a holophrase for ingest solid stuff? Isn’t it arbitrary what we consider to be atomic? Also some proposed holophrases contain far more concepts than others • So is there a clear idea of what makes a holophrase either?

35. 3 Elements Per Meaning is Arbitrary New simulations: • 4 elements per meaning • out of a total of 20 meaning elements • 3 words per utterance • 10,000 word bottleneck (4845 possible distinct meanings)

36. Types of Words Emerging

37. Conclusions • Atomic words or holophrases are not the only possibilities for protolanguages. • If agents try to express a limited number of meanings (relative to their communicative abilities) holophrasis will results. • With more meanings or fewer words forms, words become less holophrastic and more like atomic words. • The atomic word vs. holophrasis debate is not as clear cut as it might at first seem