Take the following as truth: When he dropped the ill-received jocularity to say that he had wanted, having grown up in the Midwest, to live awhile in one of the world's most beautiful cities, they were openly disbelieving--they had never been to Prague of course, and apparently, they did not know of its architectural splendors, either.
Then the following statement: "They had all been to Prague before, and knew all about its wonders." is true, false, or inconclusive?