Robert Silverberg 
To Live Again 

Paul Kaufmann is dead — but his mind lives on.And the mind of a financial genius is always in demand.Mark Kaufmann, the old man’s nephew and heir, wants it, to ensure the future of the Kaufmann empire.The ruthless and self-made John Roditis, Mark’s great rival, wants it, to give him the social status he has always lacked.And Risa, Mark’s self-willed and sensual daughter, wants what a mind like Paul’s can give, for reasons all her own.