German Philosophers in Love, from humanities professor Ettinger (MIT; Rosa Luxemburg, A Life, 1987, etc.). When Hannah Arendt was a sultry 18-year-old studying philosophy at the University of Marburg, she fell in love with Martin Heidegger, the soon-to-be-Nazi, who more or less obligingly fell in love with his Jewish student. He was in his mid-30s, married with two sons, and well known as the philosopher of Being. The steamy part of their affair lasted from 1924 until 1930 or so. She was soon in exile, and by 1933 he was a member of the Nazi Party, perhaps more out of the worst sort of opportunism than genuine ideological commitment. After the war Arendt knew something of Heidegger's craven behavior among the Nazis, including various acts of anti-Semitism within the university. Though angry at first, she was only too willing to believe his claims that he was the victim of slander and Nazi persecution. She soon warmed up to him again; remaining strangely blind to his brazen manipulation of her, she corresponded with him and visited him in Germany. Ettinger writes: ``The letters Heidegger wrote following Arendt's visits were warm, elegant, romantic, even seductive. He would recall her becoming dress, ask for her photographs, compose poems for her, remember a symphony by Beethoven they both enjoyed, describe the magic of nature, hark back to the long-ago past.'' But the reader, appetite made keen by such enticing descriptions, will want to know exactly what he said. Alas, Ettinger is stingy with quotations in general and especially miserly when it comes to the unpublished correspondence. Perhaps there are restrictions on it; she does not say. Still, the ballad of Hannah and Martin is fascinating, revealing sides of these remarkable personalities that until now have been hidden. And at a time when Arendt is finding new readers, Ettinger's little book will probably generate a new round of Arendt-bashing among old enemies.