17. A computer-implemented method of responding to a natural language sentence, comprising: parsing an initial natural language sentence to obtain at least one search term; searching, on a computer, an information source using the at least one search term and retrieving at least one pre-existing natural language text relating to the search term; reading the at least one pre-existing natural language text and storing the at least one pre-existing natural language text in a knowledge base, the reading step including the step of applying directed reasoning to resolve one or more contextual referents within the at least one pre-existing natural language text, wherein each of the one or more contextual referents is a word that refers to a previously parsed word or a previously parsed phrase in the at least one pre-existing natural language text; constructing at least one new natural language text from the at least one preexisting natural language text; generating at least one response derived from the at least one new natural language text.
18. The method of claim 17 , further comprising the step of outputting the at least one response, wherein the initial natural language sentence is a question and the at least one response is an answer to the question.