To Live Again
Robert Silverberg
 The book describes a world where all great scientists, economists, thinkers, builders and so on can store a "backup" of their personality (if they can afford the expensive procedure). Most of those who can afford it record their personality once every six months. These personalities can then be transplanted (upon the person's actual death) to other people, "living" alongside with the Host, providing him or her with a new insight on life, and on their field of expertise. . As the possession of extra personalities can be a mark of prestige, it has become fashionable in high society to buy and possess as many personalities as they have money for. Occasionally, the personalities of strong minded individuals can overwhelm the personalities of their hosts, resulting in the destruction of the host body's personality.