Ms. Brann describes her lecture: "Most people have 'mental images,' pictures and voices that don't occur through the eyes and ears but behind them. Most of these are memory images whose originals are things seen or heard in the outside world. Some, however, are inner events, imaginary images that are not copies of reality but our own inventions, for example, dreams. We call these 'images' as well. So what are they images of? What are the originals of fictive mental images? And derivatively, what are the originals of artful fictions such as epics, novels, and paintings? Of whom is Homer's Achilles the truthful portrait?"