John Stuart Mill was at the center of a revolution in man's dealing with his sexual nature. In the nineteenth century men were engaged, first, in making sex a nonreligious subject by secularizing Christ's injunction to deny the flesh; this they did initially for "prudential," that is, economic reasons. Second, they were taking unto themselves the greatest possible control, through artificial means, over their own procreation; one consequence was that, psychologically, in denying God or nature's unmitigated creativity, men were also asserting their own potential self-made quality. Mill's involvement with economics was early and long. When he was a boy of thirteen, his father had lectured to him on Ricardian economics during their daily walks. By eighteen John Stuart Mill was writing an article on "War Expenditure" for the Westminster Review, and from that time on economic articles and reviews came from his pen in a steady flow.