It was a low-research day today, with the urgent blocking out the important! One highlight, however, was a talk in Computer Science by Yoav Artzi (UW) about natural language processing. Unlike other computer-science talks I have seen in this area, Artzi is trying to represent the meaning of sentences and conversations semantically. Usually in a machine-learning method, the "meaning" of the sentence is encoded in some abstract vector space. These meaning objects are generally uninterpretable and have no compositionality or other useful structure. Artzi wants compositionality, because he wants to be able to combine the meanings of multiple conjoined sentences or clarifications in a conversation and also combine with knowledge about the world. So he is learning a semantic model (and an ontology, and a lexicon, and so on) as sentences come in. This is an ambitious project! He is working in the limited domain of interactive systems to schedule meetings and travel, to make his project feasible.