The word "Lojban" means "logic-language", but that only means that it is based on first order logic, and has a grammar based on predicates. It does not imply that the language is more rational than others.

In fact, the Lojban vocabulary has some rather odd quirks. For instance, all words that refer to animals, are based on the same place structure pattern. Except three animals (guess which!): tigers, sheep, and human beings.

There has been a rather lengthy discussion on their mailing list, where some people argued that the word know should not be a concept of its own, as it has two meanings collapsed into one: "x1 knows x2" is equivalent in meaning to "x1 is convinced that x2 is true AND x2 is actually true".

Lojban experts have also recently concluded that the word botpi (bottle) should only be used to refer to bottles that contain something.