What determines the sorts of words that children first learn?
Whether a child is raised in the highlands of Papua New Guinea or the cafes of Harvard Square, first words have a similar flavor. They include proper names for people and animals, and common nouns such as ball and milk. They include names for parts, like nose, modifiers, like hot, words that refer to actions, such as up, and words that are linked to social interactions, such as goodbye. To give a feeling for this, at the age of 15 months, my son Max knew the following words: airplane, apple, banana, belly-button, book, bottle, bye bye, car, daddy, diaper, dog, eye, kitty, light, mommy and uh oh. This is a conservative list; these are the words he used many times in different circumstances, without the need for any prompting1. At first blush, there isn’t anything to explain here. These are the words he heard, after all. And, not coincidentally, they correspond to notions that a child would be expected to understand. You wouldn’t expect a 1-year-old to start off with the words mortgage a
