In natural language understanding, there is a hierarchy of lenses through which we can extract meaning - from words to sentences to paragraphs to documents. At the document level, one of the most useful ways to understand text is by analyzing its topics.
I made an introductory talk on word embeddings in the past and this write-up is an extended version of the part about philosophical ideas behind word vectors.
S. Wang, J. Tang, C. Aggarwal, and H. Liu. Proceedings of the 25th ACM International on Conference on Information and Knowledge Management, ACM, (October 2016)