The basic idea of An Experiment in Criticism is to evaluate the quality of books not by how they are written, but by how they are read. Naturally, the author, C. S. Lewis, assumes that there is such a thing as a quality to books to be determined. To do this, C. S. Lewis describes two kinds of readers. One is what he calls the "unliterary", and the other the "literary". He proceeds to outline some of the differences between these two types of readers. For example, one characterization of an unliterary reader is that the argument "I've read it before" is a conclusive reason not to read a book more than once. In contrast, literary readers reread books many times, savoring certain passages, and attempting to glean more from subsequent readings. Literary readers identify themselves with characters in favorite books; in many ways, literary readers define themselves by their favorite books. Clive Staples Lewis (November 29, 1898 – November 22, 1963), commonly referred to as C. S. Lewis, was an Irish author and scholar, born into a Protestant family in Belfast, though mostly resident in England. ... Clive Staples Lewis (November 29, 1898 – November 22, 1963), commonly referred to as C. S. Lewis, was an Irish author and scholar, born into a Protestant family in Belfast, though mostly resident in England. ...