
312 Foundations of Semantic Web Technologies
Web pages, and the like. While (spoken) language was a “solution” to con-
veying knowledge directly from one p e rson to another, writing was a solution
to externally storing information for the purpose of later retrieval. So when
looking for large amounts of directly accessible knowledge, it seems to be a
straightforward idea to collect written texts – at least those that are available
digitally.
Still, texts in natural language are easily accessible to human inf ormation
processing only. Extracting formal specifications from arbitrary written texts
is still considered a hard problem, although intense research ...