US troops invaded Grenada in 1983, Tennessee Williams left our world that same year, and in 1983 the phrase “I ought to” appeared less frequently than the phrase “I need to” in the published word. Most students armed with a little curiosity and some library skills could discover the first two important facts by sifting through books. The third bit? That requires the use of some serious computers that have scanned, stored, and indexed almost every printed word in the English language.