Categorization is ubiquitous in human thought. The ability to process the continuous stream of information we are confronted with and turn it into manageable units is crucial for dealing both with the world around us and with our fellow human beings. We do this when we think, and we do this when we communicate. And the way we do this reveals interesting differences between different people, languages and cultures, in that the same real-world entities may be treated very differently. For example, the English speaker differentiates between fingers and toes, while for the Spanish speaker they are all referred to by the same word, dedo.

The grammar of a language can also force us to classify. When we use a pronoun in English we have to choose between ‘he’ for males, ‘she’ for females and ‘it’ for inanimates. This type of categorization runs along the lines of biological sex. In a language with a gender system all nouns are treated as either masculine or feminine — even those nouns whose meanings have nothing to do with biological sex.

Quite a different approach is taken by languages with a classifier system. Here categorization is based on fine-grained meaning, involving shape, function, arrangement, place or time interval. One such language is Kilivila (an Oceanic language spoken on the Trobriand Islands in Papua New Guinea), which has at least 177 distinct classifiers.

Mostly a language will have only one system or the other, gender or classifiers, but in a few interesting cases we find both systems together. A key language for this project is Mian, a Papuan language spoken by 1,700 people in Papua New Guinea. Mian has both a gender system and a system of classifiers in the form of prefixes on verbs of object handling or movement (e.g. give, take, put, lift, throw, fall).