Andrew, thank you very much for the thoughtful and thought-provoking analysis. As promised, I've taken a stab at weighing in on your questions. Take these with a grain of salt -- we are often strangers to ourselves, as Timothy Wilson writes in his fascinating book with that title. My experience is consistent with the rich body of psychological research that Wilson covers: the best insights into my character come not from me, but from others who know me well. With that in mind, instead of relying solely on my own biased and limited self-insight, I asked a few friends, colleagues, and family members how they would respond. I've done my best to integrate their perspectives with mine.
You asked why Susan doesn't explore the contributions of my family life to my career. Allison expressed a preference not to be in the spotlight, and we didn't feel it was right to subject our young daughters to appearing in an international newspaper, especially since they're not at an age where they can make an informed choice about it. Also, I wanted the story to focus on the ideas, rather than on me. Ultimately, I think Susan did an extraordinary job integrating the two, although I would have voted for a heavier emphasis on the evidence and less on my idiosyncrasies. In terms of balancing my time, I'm very clear on my priorities. I give to my family first, my students second, and my colleagues third. When I have free time left over, I try to help people who don't fit in one of those three categories. For time management, I do my teaching in the fall term, which means that I'm on campus four days a week, leaving around 8:30 a.m. and returning by 5 p.m. From January through July, I'm home four to five days a week, and spend at least four hours a day with family.
You make a compelling case that Susan could have discussed my family's contributions to my career. I will take the blame for that omission; when she asked if she could have dinner at our house to see me interacting with my family, for the reasons above, I declined. For what it's worth, Allison was surprised that no readers commented on the other side of this coin, which is that I work hard to support my family so that Allison can pursue her dream of staying home with our children. After earning two master's degrees and working as a nurse practitioner in psychiatry, she decided that she wanted to be home for the formative years of our daughters' lives. By the way, she was also surprised that you read frustration into her comment that I often have a hard time saying no to requests. In her words, "I tell him to say no to lessen his workload -- not for my own benefit, but for Adam's, so that he has more time in the evenings for things he enjoys, and to make sure people aren't taking advantage of his helpfulness."
As for the definition of success, your comments led me to wonder whether I should have broadened my view. I am still reflecting on this issue, but when I set out to write the book, I was interested in covering success at work, which is usually defined in terms of performance, productivity, promotions, and other objective indications of achievement. That said, I care deeply about the quality of work life -- much of my research has focused on issues of meaning and purpose, burnout, and happiness -- so I worked these topics into many of the chapters. I did devote considerable attention to the importance of boundaries in chapters 6 and 7 (for a preview, see http://hbr.org/2013/04/in-the-company-of-givers-and-takers/ar/1). Still, after reading your critique and Susan's, if I could do it over again, I would probably add a separate chapter on work-life questions.
At a fundamental level, physics makes it impossible to argue with your statement that time is zero-sum. That said, I would challenge the assumption that giving at work necessarily detracts from life at home, as a number of colleagues have done wonderful research on how contributions at work can enrich life at home. For example, Nancy Rothbard shows that engagement at work can actually boost energy at home, and Stew Friedman writes eloquently about the importance of searching for "four-way wins" that integrate work, home, community, and self. I think, for example, about Nate Andrisani, the board chair of the Make-A-Wish Foundation of Philadelphia and Susquehanna Valley, who has raised hundreds of thousands of dollars to help grant wishes for children with life-threatening medical conditions by singing Christmas carols with his kids. Leslie Perlow has also written an excellent book, Sleeping With Your Smartphone, about how to achieve better balance. I've only just begun to explore the impact of giving at work on life outside work, but Sabine Sonnentag and I found that on days where people make meaningful contributions to others at work, they feel more excitement and inspiration at home. I would love to see more studies examine strategies for being helpful at work without sacrificing other commitments.
Finally, I wholeheartedly agree that my small acts of helping pale in comparison to the herculean acts of giving and compassion that happen around the world every day. Three of my own role models are Nipun Mehta, the founder of ServiceSpace and the most purely altruistic person I've ever met; Suzanne Sutter, who walked away from her career as a senior executive to help the Make-A-Wish Foundation bring hope, strength, and joy to families facing devastating illnesses; and Robert Coghlan, a bank leader who volunteers as a firefighter, raises extraordinary sums of money for charity, and took it upon himself to gather a crew and start rebuilding New Orleans after Hurricane Katrina. Part of my motivation for writing the book was that for years, students and executives whose core values emphasize helping others have been telling me that they have to check their concern for others at the office door, for fear that it would compromise their productivity and advancement. Given that many people spend more time at work than in any other life role, I thought it was worthwhile to challenge these myths and present the full picture of the data.
I'd write more, but it's family time!