A lot of people complain that grammatical gender is confusing and difficult to learn when they take French or one of the many other languages with grammatical gender. In fact, probably more languages have gender (also known as a noun class system) than not. But if grammatical gender is so arbitrary and illogical, why would so many languages bother with it?
One pretty useful thing about grammatical gender (or noun classes) is that it often makes it easier to distinguish between several entities in a sentence. So for example, if you’re telling a story about several people, it’s annoying to keep having to say their names, but if you refer to everyone and everything with the same pronouns then your audience is probably going to get confused.
- Did you see Bernadette and Eustace and the elephant at the party last night?
- Confusing: I saw zer but not zer or zer.
- Not confusing, but repetitive: I saw Bernadette but not Eustace or the elephant.
- Not confusing and also short: I saw him but not her or it.
It’s pretty easy to come up with other scenarios where it would be useful to distinguish between people and things, or between flat things vs round things vs liquid things, or other categories that different languages use. Notice that most languages use pretty basic categories and then extend them somewhat abstractly and arbitrarily to other items, and that the more specific the categories are, the more of them the language tends to have. For example, I’ve never heard of a language that has one gender for, say, body parts, and the other gender for everything else, and I wouldn’t expect to.
It’s useful to have gender agree with other words in the sentence (like adjectives or determiners) because redundancy makes it easier for the listener to understand the speaker, especially in noisy environments when not all of the signal may get through.