One of my future goals is to know in depth about building a text-based dialog system to answer questions about a specific topic (say, Tolkien's legendarium), assume that I have a large body of article-formed facts about that topic (say, Wikipedia). Excluding the "Computer Engineering" part of the problem, I have a question:
Which (narrow enough) fields of Computer Science are involved in the problem, and how deep is the involvement of each of them? With my knowledge right now, I can only pinpoint the field of Natural Language Processing (NLP), but I don't know how deep it's involved in the problem and whether we can narrow it more. Also, I just feel that Information Retrieval (IR) and Knowledge-based System (KBS) are involved, but actually I don't know them too well. That's all I have for now.
Addition: I'll use the example of the Tolkien's legendarium to make sample facts and a sample question. Sample facts: "Melkor (known in Sindarin as Morgoth), the evil Vala, corrupted many Maiar into his service. These included Sauron, the main antagonist of The Lord of the Rings, and the Balrogs, his demons of flame and shadow" (from the Wikipedia page of Maia). The sample question: "List all named Maiar who were tempted and served under Morgoth."