The biggest danger to American stability,"" Lyndon Johnson told Doris Kearns, ""is the politics of principle""--as opposed to the art of adaptation. Kearns, who met Johnson during a 1967 stint as a White House Fellow and stayed on after the '68 abdication to help with the memoirs and the LBJ archives, has undertaken a work of broad political evaluation based on a remarkable series of uninhibited interviews. She attempts neither the investigative reconstruction of Evans and Novak (LBJ: The Exercise of Power, 1966) nor the sociohistorical placement of Eric Goldman (The Tragedy of Lyndon Johnson, 1969), but an examination of interplay between personality and institutions even more sweeping than Hugh Sidey's analogous A Very Personal Presidency (1968). In her opinion Johnson's lifelong inability to deal openly with conflict, his equation of love or non-love with performance rewarded or not rewarded, and his intense need to be needed stem from a childhood of intense parental competition. A compulsive conciliator, he was paralyzed by true differences of belief. As Majority Leader he restructured the Senate with a virtuosity that he could not duplicate from the White House. Neither the administrative bureaucracy nor the conduct of foreign affairs was amenable to the instincts of the Macher who threw away his own legislative gains in housing and employment through sheer sloppy management of executive resources and who thought Ho Chi Minh ought to share his perception of the war as ""like a filibuster."" Much in this scenario is familiar, and repeated in terms of surprising deference and generality. In some ways Kearns has produced more of an artfully padded essay than a book; indeed, the lengthy appendix outlines her approach more suggestively than much of the text. What is unique is her access to Johnson's own words and thoughts, by turns pointed, rambling, holier-than-thou, Rabelaisian--the voiceprint of a man whose appetite for the human animal in all its sweaty diversity might almost have served him in place of principle.