Many readers who loved Susan Cain‘s Quiet (about being introverted) will no doubt also appreciate her new book, Bittersweet: How Sorrow and Longing Make Us Whole. 

Her definition of bittersweetness: “a tendency to states of longing, poignancy, and sorrow; an acute awareness of passing time; and a curiously piercing joy at the beauty of the world. It’s also about the recognition that light and dark, birth and death—bitter and sweet—are forever paired.”

Publishers Weekly expands on the thesis of the book: “Cain handily traverses fields as diverse as neuroscience, popular music, religion, and business management to find instances of the transformation of pain and longing into fulfillment: the music of Leonard Cohen, for example, is ‘a transcendence delivery system,’ and in Michigan, a hospital billing department’s culture of caring for distressed or bereaved employees resulted in collecting bills faster. Though Cain’s panoramic scope covers some familiar ground (U.S. culture’s ‘tyranny of positivity’ has been critiqued before), this ambitious work impresses in its dexterous integration of disparate thought traditions into a cohesive, moving, and insightful whole.”

To what ends does appreciating bittersweet feelings bring us? Chris Schluep, Amazon Editor: “It turns out that sadness is the heart of compassion, and compassion is the heart of being human. Cain describes how sorrow and longing are adaptive traits with benefits that far outweigh the suffering they put us through. And they aren’t just human qualities. In fact, sorrow is on par with functions like digestion and breathing—it’s part of the mechanics of living.”

Kirkus Reviews offers additional info: “Cain argues persuasively that these emotions can be channeled into artistic pursuits such as music, writing, dancing, or cooking, and by tapping into them, we can transform ‘the way we parent, the way we lead, the way we love, and the way we die.’ If we don’t transform our sorrows and longings of the past, she writes, we may inflict them on present relationships through abuse, domination, or neglect.”

To what degree do you show a bittersweet orientation? Cain, along with research scientist Dr. David Yaden and cognitive scientist Dr. Scott Barry Kaufman, created a quiz you can take. It’s posted by the author as a Bittersweet excerpt at Mindbodygreen.com.