He was one of many who took up the project of developing formal semantics for natural languages, instigated by Donald Davidson in the 1960s and 1970s. He co-edited Truth and Meaning with John McDowell and published several variously influential articles in philosophy of language and mind. His book The Varieties of Reference, in incomplete manuscript form at the time of his death, was completed by McDowell and constitutes a major contemporary development in philosophy of language.
