WESTWOOD — When South Sudan got its independence last year, Lawrence Hyde was delighted. Not because of the politics. Because of his checklist.

Hyde is 88, and his lifelong quest has been to visit every independent country in the world, as defined by the United Nations. There were 192 of them before South Sudan joined (193 if you count the Vatican, which is Hyde’s preference), and he had finished the run in 2010 when he checked East Timor off his list.