Semantics and Dialogue

• While the lexicon and syntactic systems are not perfectly understood, performance on these tasks is pretty good.
• On the other hand, semantics and dialogue are much less understood.
• Semantics is about what words, phrases and sentences mean.
• That sounds easy, but what does the word "dog" mean?
• There are nice syntactic ways of creating the meaning of a sentence from its constituents. For example, Fillmore's case frame system has got a lot of agreement. Still even within this it's not perfect.
• A lot of meaning is also left out of sentences and just assumed.
• This becomes even more difficult with dialogue.
• How do different sentences combine to make meaning?
• What happens during a conversation to reach agreement, and convey new information.
• Gricean implicatures help, but they just start.