A line of reasoning used in recent research on language acquisition assumes that a child acquiring the language has only two reliable sources of information available about the target grammar: a set of grammatical principles and the primary data of the language spoken around him. A third kind of evidence, negative evidence, would be helpful but is…

In the first section a sketch of a tense logic is presented and a mechanism is suggested for including aspects of the tense logic into the Grammar (theory of language). Specifically, several grammatical structures are shown to incorporate temporal features. A semantic projection mechanism is utilized to amalgamate the temporal features in elements…