the neolithic began with evidence of constructed settlements.That was the original definition. Today we have several standards of efinitions ( lithic industries and polishing of tools and celts) . Theres no agreed upon TIME of inititiation of the neolithic because there was evience that paleolithic industry was in use in the Americas till quite late(Although settlement in community tructures had been brought with the folks who first arrived).
Look up the one who coined the terms paleolithic and neolithis. Im ure you have the guys name in your class notes. He was some French guy.