From G.K. Chesterton (from Heretics, 1905):

Now, in our time, philosophy or religion, our theory, that is about ultimate things, has been driven out, more or less simultaneously, from two fields which it used to occupy. General ideals used to dominate literature. They have been driven out by the cry of "art for art's sake." General ideals used to dominate politics. They have been driven out by the cry of "efficiency," which may roughly be translated as "politics for politics' sake." Persistently for the last twenty years the ideals of order or liberty have dwindled in our books; the ambitions of wit and eloquence have dwindled in our parliaments. Literature has purposely become less political; politics have purposely become less literary. General theories of the relation of things have thus been extruded from both; and we are in a position to ask, "What have we gained or lost by this extrusion? Is literature better, is politics better, for having discarded the moralist and the philosopher?"

G.K. Chesterton (found in an issue of Gilbert Magazine):

"The highest outcome of an interest in literature is a finer interest in life; and bad literature as well as good may throw a light on life, if we have learnt to know light from darkness."

From C.S. Lewis' Introduction to St. Athanasius "On the Incarnation":

The only palliative is to keep the clean sea breeze of the centuries blowing through our minds, and this can be done only by reading old books. Not, of course, that there is any magic about the past. People were no cleverer then than they are now; they made as many mistakes as we. But not the same mistakes. They will not flatter us in the errors we are already committing; and their own errors, being now open and palpable, will not endanger us. Two heads are better than one, not because either is infallible, but because they are unlikely to go wrong in the same direction. To be sure, the books of the future would be just as good a corrective as the books of the past, but unfortunately we cannot get at them.

Archbishop Fulton Sheen:

Any book which inspires us to lead a better life is a good book.

From a blogpost entitled "Two Traps for the Pious":

This is almost an accidental, automatic fault. It can be overcome, as Fr. Groeschel points out, by reading good literature and opening your eyes to the plight of the poor and intentionally entering into solidarity with the poor by divesting one's self of some of the incidental benefits of a devout life.

From Language Police: How Pressure Groups Restrict What Children Learn by Diana Ravitch:

I began this quest with a strong belief that schools are supposed to lay a foundation for love of literature by exposing children incrementally, based on age appropriateness, to the best writings of our common language and, to the extent possible, to the best writings from other cultures. There are so many superb novels, short stories, poems, plays, and essays to choose from that it is impossible for any student to read them all. But this fact makes it all the more important that teachers make the effort to identify the writers and works that will broaden their students' horizons beyond their own immediate circumstances and reveal to them a world of meanings far beyond their own experiences. Great literature is "relevant" not because it echoes the students' race, gender, or social circumstances, but because it speaks directly to the reader across times and cultures. A child who is suffering because of a death in the family is likely to gain more comfort from reading a poem by John Donne or Ben Jonson or Gerard Manley Hopkins than from reading banal teen fiction about a death in the family.