Dialogue is not conversation.

dialogue in fiction, as in plays, is most interesting when an action is implied in every line. This level of intensity in fictive speech—action implied in every line—is extremely difficult to maintain.

Dialogue is a skill best learned by people who enjoy talking and listening to others—particularly listening, picking up the accents, rhythms, dialect, and slang of various groups. Loners such as Lovecraft often write it badly, or with the care of someone who is composing in a language other than his or her native tongue.

writing dialogue for an earlier era involves invention, not just research and mimicry. Fowles, in commenting on his own work1 reinforces the point that dialogue is a semblance of speech rather than an attempt to duplicate it: