Michael Bloomberg's achievements attract superlatives. He is one of America's richest men and one of its most generous philanthropists. He is a self-made mogul who devised a sophisticated data system that became the basis of his trail-blazing information company. He made himself mayor of the country's most demanding city without any prior political experience, prevailing in a Democratic stronghold as a Republican and, once in City Hall, vainly promoting a list of bold projects that refused to recognize limits. In fact, when Bloomberg did run into a limit - a two-term limit for New York's mayors - he changed the law to overcome it. Yet Bloomberg is a most unconventional super-achiever. He has never won over a crowd with his speaking prowess. Rooms do not hush with anticipation when he enters. Celebrity stalkers do not haunt him. He jealously guards his privacy and somehow New Yorkers have adjusted. Though accustomed to flamboyant politicians, they elected and re-elected him without ever really warming to him. This is the central paradox of Michael Bloomberg that Joyce Purnick traces in her biography. He is a great success who has repeatedly defied the standard models for success. He bends to convention only to suit his self-interest, otherwise stubbornly charting his own paths. He is Bloomberg, the willful center of his world, confident in his right to be there.