Computational and Evolutionary Aspects of Language Written by: Martin Nowak, Natalia Komarova, and Partha Niyogi Presentation by: Amerika Adams, Isaac Huang, and Margaret Kuwata

Purpose Attempt to formulate a synthesis of three theories. Addresses the importance of human language. Addresses the following questions: 1. What is language? 2. What is grammar? 3. What is learning? 4. How does a child learn language? 5. How formal language theory and learning theory can be extended to study language as a biological phenomenon and as a product of evolution.

Formal Language Theory It is a mode of communication It is a crucial part of human behavior It is the sequencing of small units into bigger structures. There are rules for word grouping.

What is language? The alphabet is a set of symbols Sentences are strings of symbols Language is a set of sentences Example: Binary Language

What is grammar? It is a finite set of rules specifying a language. Expressed in terms of “rewrite rules”

Languages, Grammars, and Machines. Correspondence between languages, grammars, and machines. Regular Languages are generated by finite-state grammars which is equal to finite-state automata. Finite-state automata have a start, a finite number of intermediate states, and a finish. A particular run from start to finish produces a sentence.

Learning Theory Learning is the ability to generalize beyond one’s own experience to new circumstances. Learning theory describes the mathematics of learning with the aim of outlining conditions for successful generalization. Theory of Universal Grammar (UG)

What is special about language acquisition? We learn the grammar of generative systems. The process occurs without being instructed about rules. The set of all computable languages is learnable by an algorithm that memorizes the rules.

Evolutionary Language Theory The evolution of language occurred in several incremental steps that were guided by natural selection. The theory states that by taking a population of individuals and with each individual using a particular language, the successful ones are able to communicate which results in a pay-off that attributes to fitness. Languages change overtime because the transmission from one generation to the next is not perfect.

Agreements 1. Language is a crucial part of human identity and behavior. 2. Language has evolved through Darwinian dynamics of natural selection. 3. That learning is the ability to generalize beyond one’s own experience. Not just modeling others.

Disagreements 1. The set of all computable languages is learnable by an algorithm that memorizes rules. (?) That children have a restricted set of innate languages they could learn correctly.