Abstract
English negative sentences developed as follows: (a) ic ne secge→(b) I ne seye not→(c)I say not→(d)I not say→(e)I do not say→(f)I don't say. This transition is argued to be triggered by the change in the syntactic status of not. With ne in Neg, not was first an adverb in the adjunct position of INFL' and served to semantically strengthen ne in Neg. Then, as ne became phonetically weakened, not came to occupy [Spec, NegP] in order to take over the function of ne expressing sentential negation. After the loss of ne,not came to occupy Neg and express sentential negation by itself. Finally, the contracted form of not,n't, appeared as a result of not being weakly stressed and encliticized onto do.