The number after the topic is the page on which the quote was found.
Leisure 258 "Leisure without literature (or books) is death." Latin. Dictionary of Foreign Terms
Leisure xv "Leisure is distinguished from idleness; the Utopians have a passion for learning and self-improvement, and they believe that leisure must be used for the cultivation of the mind." Introd. John Anthony Scott. Sir Thomas More, Utopia.