The first crank of the cultural ratchet: Learning and transmitting concepts through language.

Abstract

Human knowledge accumulates over generations, amplifyingour individual learning abilities. What is the mechanism ofthis accumulation? Here, we explore how language allows ac-curate transmission of conceptual knowledge. We introduce anovel experimental paradigm that allows direct comparison oflearning from examples and learning from language. In ourexperiment, a teacher first learns a Boolean concept from ex-amples; they then communicate this concept to a student in afree conversation; finally, we test both teacher and student onthe same transfer items. We find that learning from languageis both sufficient and efficient: Students achieve accuracy veryclose to their teachers, while studying for less time. We thenexplore the language used by teachers and find heavy relianceon generics and quantifiers. Taken together, these results sug-gest that cultural accumulation of conceptual knowledge arisesfrom the ability of language to directly convey generalizations.