The Dimensions of Context-Space

Contexts have historically been either ignored completely or else treated as black boxes, as indivisible atoms. About a decade ago, as part of our work on building the l arge Cyc ® knowledge base of human common sense and common knowledge, our group began to study and harness the internal structure of that “atom”. Each context was said to have assumptions and content; there was a theory of importing assertions across contexts; contexts were fully reified first-class terms in the CycL representation language; they were partially ordered by specialization to control visibility and access to content; and so on. That 1989-91 work turned out to be inadequate: it was too expensive to do nontrivial lifting (importing); to explicate the assumptions of each context; and to place each assertion/query into the proper context.