Is it common practice to lie in a memoir? Not for accomplished memoirists, according to Mary Karr. The Art of Memoir (Harper Collins), in part a how-to book, distills 30 years of teaching and writing memoir. The author of three best-selling memoirs, Karr discusses her commitment to finding the truth and relates it to having been lied to as a child. She wonders if writers of memoir were told more lies by their parents than other kinds of writers. She reveals that writing is a painful process, that it takes years for her to write a book. She throws out hundreds of pages in the editing process. She discusses maturing beyond her youthful impulse to present a false self-portrait. As a beginning memoirist she tended to be pretentious and longed to be T.S. Eliot. Her real goal? To write from the true self. This book's real subject? To learn how to read the self. She describes running a Geiger-counter over the heart to find the truth.