This conversation reminds me of Bill Cosby's joke: Philospher: "Why is there air?" Jock: "Everybody knows why there is air. There is air to blow up basketballs and footballs." I understand David's quest for a philosophical, notional explanation of a sentence, but I would suggest that it ends up detracting from teaching. Every speaker of English (and thus every student) intuitively understands what a sentence is. They understand that "Bread" is not a sentence, nor is "old bread," even though "old bread" contains a "complete thought" -- "The bread is old." Attempts to get students to come to terms with the philosophical implications of sentences will simply take time away from the more important task of getting students to understand how sentences work, and how complicated sentences are complex embeddings of simpler sentences. Once again I suggest that ATEG is ignoring the important questions -- which grammatical constructions are pedagogically important, how should they be defined, and how (and when) should they be taught? Ed V.