Doctor Livingstone, I presume?

A humorous greeting. The phrase refers to Scottish explorer David Livingstone, who was presumed lost in Africa in the mid-19th century. When reporter H.M. Stanley finally located him, he supposedly greeted Livingstone with this now-famous phrase. You must be the gentleman I'm looking for—Doctor Livingstone, I presume?

Jocular You are who I think you are, are you not? Oh, there you are. Doctor Livingstone, I presume?

A 19th-century explorer named Dr. David Livingstone became something of a national hero through his articles and lectures about his adventures in Africa. In 1864, Livingstone led an expedition to discover the source of the Nile. When little to nothing was heard from or about Livingstone after many years, Europeans and Americans became concerned. In 1871, the publisher of the New York Herald hired Henry Stanley, a newspaper reporter, to find Livingstone. Heading a group of some two hundred men, Stanley headed into the African interior. After nearly eight months he found Livingstone in a small village on the shore of Lake Tanganyika. As Stanley described the encounter, “As I advanced slowly toward him I noticed he was pale, looked wearied . . . I would have embraced him, only, he being an Englishman, I did not know how he would receive me; so I . . . walked deliberately to him, took off my hat, and said, ‘Dr. Livingstone, I presume?' The phrase “‘Dr. Livingstone, I presume?” caught the public's fancy, and any number of would-be wits greeted friends with it until the phrase lost all traces of cleverness. But that never stopped people from continuing to use it long past the public's memory of who Livingstone or Stanley were.