title_body: What makes lojban such a "logical" language?
upvoted_answer: Lojban was designed with a few key features in mind, which are ultimately why it claims the title of "logical" language. 
  
  First it's good to know that a logical language actually means something pretty specific. It's usually built on predicate logic, and a desire to express any logically-expressible statement unambiguously. No two statements are allowed to mean the same thing, and no statement is allowed to mean two things.
  
  In this sense, Lojban fulfills the literal criteria for what counts as a logical language. There's also the colloquial sense, though - the way people think about it, when someone says "logical language."
  
  It is designed to be a regular language. This gives it a few key properties that make it easier for computers to process (though it's still an immensely complicated task to implement). Most of these properties are mathematical, and you can read them on the Wikipedia page. However, what it means in an intuitive way is that no word or word phrase's meaning changes based on words it's not adjacent to. That's a nice property when you're a computer and have a hard time maintaining a sense of context.
  
  Lojban also has no irregular forms or rule exceptions whatsoever. All words are constructed based on specific properties that are clearly delineated, using roots that are unique and are intended to mesh with each other as-is. 
  
  This means that any construction which can be built in a logical form can be written completely and uniquely in Lojban. There are no ambiguities between forms. Note, though, that this is commonly confused with "the language has no ambiguity." It's possible to be ambiguous in Lojban, but only intentionally, and that ambiguity is unique to the way you wrote it.
  
  It also allows for systematic, structured learning and use. New words fit into the existing grammar and structure without any other prompting, once you know what they mean and how they're used. No additional grammatical structures are needed to use any words, once you know them.