Believing that a standard autobiography would be an ""arrogant exaggeration of ego,"" superlawyer Nizer has conceived something far more hubristic--an ""autobiography of the mind,"" in which he flits ponderously from subject to subject, issue to issue, celebrity to celebrity, writing with pseudo-profundity and no special grace (and not always with personal involvement) about science, politics, medicine, music, women's lib, psychology, and, of course, The Law. True, few attorneys can capture the ins and outs of cagey, suave litigation with Life in Court flair, so when Nizer is being specific about legal wrangles--his first case (Brooklyn pushcarts), the Susann-Capote libel duel, defending Igor Cassini from Bobby Kennedy and Carnal Knowledge from obscenity charges--all is well. And among the few unadorned pieces of memory are some gems: teaching English to night-school immigrants, a recreation of a great law prof's Socratic method (far better than that in Paper Chase or One L). But Nizer's choice cases have already been chronicled, and he declines to give us a simple life history flee of moralizing and sentimental philosophy. What remains? Opinions (anti-impeachment, anti-death-penalty, free heroin for addicts, too much freedom-of-press), advice (how-to-memorize-a-speech, how-to-tell-a-liar), anecdotal homilies (Live and Let Live, Where There's A Will. . .). And undistinguished portraits of famous clients and advisees: Jimmy Walker, LaGuardia, Truman, Adlai, LBJ, the astronauts, tycoon Armand Hammer. Unfortunately, when Nizer himself pops up in these portraits--warning Stevenson, ""If you start kissing babies, you'll be embarrassed and so will the babies,"" urging Truman to support new-born Israel--he seems a rather pompous stranger. We would have liked to have gotten to know him better--and his deep thoughts not quite so well--in this floridly erratic, wandering credo.