Lewis begins by drawing a distinction between "gift-love" and "need-love," defining the first as the type of love which motivates a man to work and plan for his family's future well-being although he will not live to see its fulfillment, and the second as that which sends a frightened child running to his mother. There follows a scholarly yet warmly conversational discussion of the four loves known to man: affection, friendship, eros, and charity. In conclusion, the author says, "We must try to relate the human activities called "loves" to that Love which is God." He explains that the Creator implants in us both gift-loves, which are natural images of Himself, and need-loves, which are correlatives. "But in addition to these natural loves God can bestow a far better gift…He communicates to men a share of His own divine gift-love: Love Himself working in a man."
The author's candid reflections help the reader define and sort out the types of love common to human experience, and to determine their right and proper places and functions in relation to one another and to the over-arching love of God which is the wellspring of all human loves.
I would suggest that this book be read incrementally, with time for digestion and reflection between chapters, and special attention given to the final pages in which all the concepts are tied together.