The model is based on the grammatical structuring of factuality in languages such as English, and addresses the three aforementioned challenges.
it rests upon a three-fold distinction of the factuality scale, it acknowledges the possibility of different sources (with potentially contradictory views), and it is strongly grounded on the information provided by linguistic operators (including polarity and modality particles, predicates of different types, and subordination constructions) together with their cross-level interactions.