My friend Bob Nylen died over the holidays. He'd been pretty sick for about four years, and then very sick for a couple of months. He was 64.

You might not know his name—yet. The cofounder of New England Monthly and Beliefnet.com, Bob was more a magazine and media guy than a full-fledged denizen of BookLand, though in the Ashfield, Mass., community in which he lived, he was surrounded by some great authors who were also his friends: Tracy Kidder, Richard Todd, Jonathan Harr, to name just a few. But Bob will officially join their ranks, as book author, in May, when Random House publishes his memoir, the perfectly titled Guts. The story of a middle-class American guy known for his fearlessness—Bob won two Purple Hearts, a Bronze Star and other medals in Vietnam—Guts is partly the story of his personal journey in war, in business and in life, and partly an examination of manhood, of what it means to be brave and strong and, well, manly.

Bob would be the first person to admit that the book is a hybrid, and that some of his merging of the personal with the philosophical was hard to navigate. Still, there are passages of true beauty, as when Bob suggests that the drive that got him through Vietnam and then the perils of publishing was born of his failure as a child, to defend his disabled sister from some aggressive teenagers. “At the time,” he wrote, “I loved King Arthur, Charlemagne, and the Song of Roland. I imagined myself... a heroic knight like Galahad.... [But] as I slunk away from the soda fountain, every step widened the gulf between my journey and the paths my heroes had chosen. By the time I got home, the gap was a canyon.”

Passages like this are interspersed with truly harrowing, Dispatches-like scenes of the jungles of Southeast Asia, tense moments starting businesses and what those of us who knew him would call Nylenesque commentary on everything from his mother to his beloved wife, Kit, to Marcus Aurelius' Meditations. This was a guy, after all, who told me not long before he died that he had quizzed his hospice nurse on exactly what was going to happen to his body in the coming weeks. “You put that poor woman through this?” I said. “I couldn't help it,” he replied. “You know that at heart, I'm really a 12-year-old boy.”

And so he was—in his passion, his energy, his curiosity about everything. And I think it's just that reckless energy, that nimble willingness to experiment, that fearlessness that I'll miss the most—because it's what we all need the most, both in our business and in life. In his mid 50s, Bob, a lifelong “print guy,” co-founded a Web site; at 60-something, he sold a book. If he doubted himself or was afraid, henever said so—at least not to me.

In these difficult times, I wish we all had Bob's passion and commitment and energy. And while it's always hard to judge a friend's work—especially when that friend is recently gone—I suspect that readers will find Guts an inspiring combination of Michael Herr's war reporting and Tobias Wolff's childhood memoir, This Boy's Life. From my perspective it is that—and something more. Guts is a smart and funny and brave and self-deprecating and sometimes relentless book, just like the man who wrote it.

I was lucky to know Bob for 20 years. Come May, the rest of the world will have nearly the same privilege. May we all learn from his example.

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