A statistician who injected fresh ideas into quantitative biological experiments and a pioneer in the theory of genetics, Ronald Aylmer Fisher is the author of Statistical Methods for Research Workers (1925). This "bible" of applied statistics, which remained in print for fifty years, is considered so difficult to read that a colleague once remarked, "no student should attempt to read it unless he had read it before."

Fisher, a surviving twin and the youngest of seven children, was born in the London suburb of East Finchley, England, on February 17, 1890. He was a precocious child. Supposedly, when he was about three years old, he questioned the process of successively dividing the number 2. He finally decided, on his own, that "half of a sixteenth must be thirty-toof."

During his school years at Stanmore Park and Harrow, Fisher developed the habit of seeing complex geometrical problems in his mind. His poor eyesight...