“This book is about manliness,” begins the preface of a provocative new book by Harvey C. Mansfield, William R. Kenan, Jr., Professor of Government at Harvard University.

What is that? It’s best to start from examples we know: our sports heroes, too many to name; Margaret Thatcher, the British prime minister who is the mightiest woman of our time (What! a woman, manly?); Harry S. Truman, who said “the buck stops here”; Humphrey Bogart, who as Rick in Casablanca was confident and cynical–cool before “cool” was invented; and the courageous police and firemen in New York City on September 11, 2001. Manliness seeks and welcomes drama and prefers times of war, conflict, and risk. Manliness brings change or restores order at moments when routine is not enough, when the plan fails, when the whole idea of rational control by modern science develops leaks. Manliness is the next-to-last resort, before resignation and prayer.

Here, Mansfield answers a few questions about his new book:

Q: Why did you decide to write a book on manliness?

A: We today have embarked, not fully realizing what we are doing, on a radical experiment to make a society never before seen in history–a gender-neutral society in which your sex matters as little as possible and does not give you your rights, your duties, and your place. Manliness, a quality that prevails in one sex, stands in the way of this aspiration. Is it obsolete? My book shows what manliness brings to a free society: confidence in the face of risk and trouble from those who love to risk too much.

Q: You identify “educated women” as the primary target audience for your book. Why?

A: Women are better listeners than men, and I want to persuade them of the need to make room in their lives and thoughts for manliness. Even if they don’t agree, they will be interested to see what I make of manliness and of differences between the sexes. I assume men will want to learn about manliness. Anyway, they ought to.

Q: What is the difference between “manliness” and “masculinity”?

A: “Masculinity” collects traits that are common to all or almost all males; these are close to the male body. “Manliness” is a quality of the soul only a few men have, and they typically look down on most men for not being manly. Nowadays “masculinity” is sometimes used to depreciate manliness by critics who don’t care for it.

Q: Who’s manly and who’s not?

A: Among actors John Wayne and Clint Eastwood are manly, Alan Alda and pretty boys like Leonardo DiCaprio and Jude Law are not. Harry S. Truman was manly, Jimmy Carter is not. Any novel by Elmore Leonard revolves around a manly man, usually a criminal. But my point is not to provide criteria for judging who is manly. Most people know that already. They don’t know how to judge what is manly. What do manly men do for us? Are they more trouble than they are worth?

Click here to read an interview with Dr. Mansfield that appeared in The Wall Street Journal (March 4).