James Schall pointed to a couple of reasons why one should build a personal library: one should not presume that merely having books and knowledge is enough, because as he wrote, “Knowledge alone won’t save us … The essential thing is the ‘inclination to know.’” Having an “inclination to know” is what Schall considers the constitution of our hearts as rational beings, and this is precipitated because we can know.
Quoting C. S. Lewis, Schall noted, “Those who read great works … will read the same work ten, twenty, or thirty times during the course of their life.” When building a personal library, the books contained therein should be books upon which one may rely if only for points of reference. To read books once and never consider it again is wasteful. There may be seasons of life when a book speaks to us in ways that have not spoken. A great illustration of this is any book in the Bible; the same book may be read several times, but each time something different may leap from the pages to one’s amusement. Lewis considered a book once read a book not read at all.
When building a personal library, the books contained therein should be books for which one has a desire. Quoting Samuel Johnson, Schall noted that “it is better when a man reads from immediate inclination.” If a topic or study piques the interest of the reader, they must acquire works pertinent to their mind’s curiosity. If they permit the topic or subject matter to “grow stale and inert” in their minds so that they do not regard them again, Johnson wrote that “it is a chance if you again have a desire to study it.” To have books for cosmetic value is itself wasteful.
“The important thing is not to read, but to understand.” Perhaps this is the reason many do not have personal libraries or even an interest in reading—they cannot understand. However, we all must crawl before we can walk, and walk before we can run. “If we find ourselves bored, it is not because there are no interesting things about us to know … for us, to know is also to be.” It may not be the great classical works that have endured the test of time—which attests to their worthiness of reading—that occupies our shelves, but filled our shelves must be.
Knowledge begins on an elementary level subject to a person’s individual interests and desires. This will cultivate the desire to know. A teacher can tell by the light in a student’s eyes the day they first wake up and want to know. This awakening occurs when the mind learns to crawl, and eventually, walking and running will follow.
 James V. Schall, The Life of the Mind: On the Joys and Travails of Thinking (Wilmington, DE: ISI Books, 2006), 9.
 C. S. Lewis as quoted in Schall, Ibid., 8; cf. p. 12.
 Samuel Johnson as quoted in Schall, Ibid., 9.
 Ibid, 14.
 Ibid, 10.