Natural language processing is the branch of artificial intelligence that allows computers to recognize, analyze and replicate human language. But when it’s hard enough for humans to say what they mean most of the time, it’s even harder for computers to get it right. Even when they do, we might not like what we hear. In this week’s episode looks at sentiment analysis, search engine prediction, and what AI and human language can teach us about each other, with guests Alvin Grissom II of Haverford College and Alexandra Olteanu of Microsoft Research.