Thinkers aren't always interesting to read about, but Hannah Arendt was at least an interesting thinker who wrote dense, no-fat prose and, above all, stimulated the reader's thinking. In Wesleyan University professor Young-Bruehl, an Arendt student, she has not found a biographer of like qualities. After a plodding depiction of Arendt's youth in East Prussia (that includes quotes from her parents' meticulous notes on her two-year-old behavior), Young-Bruehl follows her subject to Marburg, where she was a student of Martin Heidegger's and, for a time (in 1924-25), his lover. Since Heidegger later told Arendt that she had been the inspiration for his work in the period 1923-28, Young-Bruehl is able to credit Arendt (at least vicariously) with Heidegger's masterpiece, Being and Time. The personal relationship with Heidegger meant that Arendt had to go elsewhere to complete her studies, and she moved on to Heidelberg and Karl Jaspers. Amid the tedious details of student friends and an exposition of Arendt's dissertation on Augustine's concepts of love, the first, and as it turns out only, encounter with political involvement begins to take shape in Arendt's adoption of a Zionist stance. (In one of Young-Bruehl's typically pedantic locutions: ""Arendt's way of acting as a Jew was provided by the Zionists."") In 1933, she moved to Paris (after a short period in Berlin, when she helped Communists hide from their Nazi pursuers), and continued to be active in Jewish causes. In 1941, together with her second husband Heinrich Blucher, Arendt emigrated to New York City--carrying with her the last writings of Walter Benjamin, who had committed suicide when his escape from France was thwarted at the Spanish border. (The story of the manuscripts, unpublished for several years thereafter, holds special interest here.) Her involvement in Jewish affairs in the 1940s is a central part of Young-Bruehl's story. Arendt adopted an idiosyncratic position on a Jewish state in this period-arguing that Palestine should follow India in becoming a part of the British Commonwealth--and opposed the establishment of a Jewish state as such, a position that reflected her attachment to republican forms of government. During this period, too, she worked on the book that would make her famous, The Origins of Totalitarianism, published in 1951. From then on--with the notable exception of the fireworks surrounding her Eichmann in Jerusalem--Arendt settled into a routine of writing, teaching, and traveling; Young-Bruehl, correspondingly, settles into a string of prÃ‰cis and a hagiography of New York intellectual life. For those not already fascinated by Arendt, and not responsive to uncritical exposition, these years of her greatest accomplishment will weigh especially heavily in Young-Bruehl's generally heavy-handed retelling.