Mr. Stephen's third volume is chiefly occupied by the history of the later Utilitarians, and the expansion of their cardinal principle in its application to a changing temper of the times, under the leadership of John Stuart Mill. We have, first, a closely written and critical description of this remarkable man's early life, his stringent educational training, the development of his opinions, and their influence upon the orthodox tenets of the sect. Upon all these subjects Mill has left us, under his own hand, more intimate and circumstantial particulars than are to be found, perhaps, in any other personal memoir. The writer who tells his own story usually passes hastily over boyhood; the ordinary biographer gives some family details, or endeavours to amuse us with trivial anecdotes of the child who became an important man. J. S. Mill hardly alludes to any member of his family except his father, and his early days are marked by a total absence of triviality. He was bound over to hard intellectual labour at home during the years that for most of us pass so lightly and unprofitably at a public school; he was a voracious and indefatigable reader and writer from his youth up, with a wolfish hunger (as Browning calls it) for knowledge; he plunged into all the current discussions of philosophy and politics; he became a practised writer and made a good figure at debating clubs; he became so intent on the solution of complex social problems as to acquire a distaste for general society; his mental concentration blunted his sensibility to the physical passions that so powerfully sway mankind.