In one aspect of the invention, a book comprises at least one page
visually displaying information about a subject, wherein the visually
displayed information is conveyed from a first perspective; and an audio
device operable to aurally display information about the subject, wherein
the aurally displayed information is conveyed from a second perspective
that is different than the first perspective, and wherein the information
displayed aurally is different than the information displayed visually.
By receiving different information from different perspectives, a user of
the book can draw more and better inferences, develop more thorough
conclusions and thus better understand the subject of the book.