Back in 1930, young Sam Taylor, offspring of a Mormon plural marriage and budding nonconformist, came upon the Saints ""depicted with detached urbanity"" by Bernard DeVoto in an American Mercury article, and felt a call to challenge Mormon censorship himself, This idiosyncratic volume is the latest fruit of that lifelong labor: half jaunty, disjointed dissenting history, half tales from the Mormon underground. Taylor's premise is that in officially renouncing (though tacitly countenancing) plural marriage to achieve the benefits of statehood, the Mormon hierarchy traded principle for economic and political power, an idea that he found in embryo in DeVoto. Here it's extended through condemnation of the wrongs inflicted upon subsequent plural wives (and affirmation that plural marriage persists today); contempt for the mercenary character of the Saints' leadership; and contrast between the 1930 Centennial's celebration of ""progress and achievement"" and the 1880 Jubilee's praise of ""brotherhood and the Golden Rule,"" But Taylor is an affectionate apostate, committed to the ""essence of Mormonism"" as DeVoto also articulated it, so his tales of the mad expedition to authenticate the Book of Mormon by discovering ""Zarahemla,"" fabled Colombian capital of the ""Nephites""; of the wildly successful practical jokes of Brigham Young University coach Gene Roberts; and of his own misadventures at BYU are undemanding, good-natured fun. Best, though, is the affecting story of Campus ogre and closet researcher M. Wilford Poulson, whose quest for every scrap of early Mormon material ""meant he would never write page one"" of his projected history. And those who look suspiciously at the Mormons in their midst will learn a surprising thing or two from Taylor's account of his own Redwood (Calif.) Ward. Not a treatise, as the title suggests, but one unconstrained Mormon at large.