 To implement his objective, Montague applied the method which is standard for logical languages: model theoretic semantics. This means that, using constructions from set theory, a model is defined, and that natural language expressions are interpreted as elements (or sets, or functions) in this universe. Such a model should not be conceived of as a model of reality. On the one hand, the model gives more than reality: natural language does not only speak about past, present and future of the real world, but also about situations that might be the case, or are imaginary, or cannot be the case at all. On the other hand, however, the model offers less: it merely specifies reality as conceived by language. An example: we speak about mass nouns such as water as if every part of water is water again, as if it has no minimal parts, which physically is not correct. For more information on natural language metaphysics, see Bach 1986b.