Jim H. at his blog Wisdom of the West quite correctly takes issue with Jill Lepore's shallow comparisons of history and fiction:
Lepore, I believe, misunderstands fiction. She says: "Fiction, in other words, can do what history doesn’t but should: it can tell the story of ordinary people." As she acknowledges, this view is a bit outdated because much current history is precisely the study of private life. But, her equation is at the level of story: history and fiction tell stories about people, great and small. This is a shallow view of fiction. Sure, history can tell stories about events—how they happened, why they happened, what their consequences were, etc. And fiction can tell similar stories, the only difference being that the fictional stories are putatively made up.
Unfortunately, he then reverts to the usual sort of explanation of what makes fiction unique:
However, as a historian, the writer cannot enter into the consciousness of his subject. The historian cannot say how richly succulent the juice from the veal loin Henry IV ate the night he learned of Richard II's death tasted as it dribbled down his chin. The historian cannot say how delicious Cleopatra's wet sex smelled to Marc Antony as their boat sailed down the gentle Nile on a warm summer evening. The historian cannot say how the point of the ice axe felt as it entered Trotsky's head. . . .
Actually. the fiction writer can no more "enter into the consciousness of his subject" than can the historian. There is neither a "consciousness" to enter nor a "subject" whose consciousnesss is revealed. There are words on a page. The skillful fiction writer might make us believe we are observing a "person," that we are exploring his/her "mind," but such explorations are hardly authoritative soundings of what the human mind is really like. They are a convention of fiction writing by which an illusion of intimacy is created, but they certainly cannot withstand scrutiny as an account of human consciousness.
Neither can the novelist, any more than the historian, "say how delicious Cleopatra's wet sex smelled to Marc Antony" (I'm pretty sure I don't want to know that, anyway). Or rather, both the historian and the novelist can say what this was like, but I don't see how the novelist has any more special access to such information than the historian. It's a convention of history-writing that the author doesn't ordinarily dwell on this sort of thing, and a convention of a certain kind of fiction ("psychological realism") that the author does, but finally the novelist has no more idea than anyone else what olfactory sensations Marc Antony might have experienced on his trip down the Nile. A writer might offer us a fictional "Marc Antony" whose sensory experiences are described for us, but this hardly gives the novelist an edge over the historian when writing about actual historical events.
Fiction does do more than tell stories about people, but it can also do more than pretend to "enter into the consciousness" of people. To believe this by now fairly standard technique of faux-psychological probing into the minds of characters is the only thing that separates fiction from history, or from film, is a rather impoverished view of the possibilities of fiction as a literary form. Indeed, the purely literary possibilities of the "interior" strategy were, it seems to me, pretty much exhausted in the fiction of Woolf, Joyce, and Faulkner. Adventurous writers following on their achievement--Beckett, Burroughs, Barthelme, Sorrentino--discovered fresh ways of extending their experiments in form, of showing us how fiction can be different not just from history or film, but from previous versions of fiction as well. More such discoveries can be made.