Some men write their lives to save themselves from ennui , careless of the amount they inflict on others. Others write their personal history, lest some kind friend should survive them, and, in showing off his own talent, unwittingly show them up. Others, again, write their own life from a different motive - from fear that the vampires of literature might make it their prey. Charles Babbage, Passages From The Life Of A Philosopher, 1864